Build this fantastic model sail boat!

Build a Model Sailboat !!

The information used for the " Model Sail Boat Building, Making A Wooden Star45 R/C Sailing Model" includes posts found on the companion blog: The Star 45 R/C Model Sail Boat - Builders Journal


"Model Sail Boat Building, Making A Wooden Star45 R/C Sailing Model" is a start to finish, step by step, building manual. Including directions for covering a wooden star with fiberglass.

With the popularity of radio-controlled models, the number of people interested in owning a model yacht has also grown - in geometric range. As with model aircraft, the choice of sailing models runs the gamut from child's toy to sophisticated craft.

Over the past 30 years I have fielded many questions regarding the choices and considerations which go into selecting a radio-controlled sailboat.

Four questions are asked over and over by prospective skippers: How do the radio-controls work? How much do they cost? What do I look for when I buy mine? And, where can I get plans and instructions for building a sailing model?

The modern R/C model sailing craft is as different from a toy boat as a museum display model is from a child's tinker-toy creation. A model sailing craft operates with the same sophistication of design as any full-sized yacht

The AMYA STAR 45 Class discussion group is a terrific place to exchange ideas and talk about building Star 45 models for racing in AMYA regattas.

Feel free to contact me, Dave Mainwaring mainwaring @ rcn.com

The Star45 Model Sail Boat, A radio controlled, R/C, Sailing Model

The Star 45 is a 45" long hard chine hull; semi-scale model of the full-size Olympic Star. They weigh 12 pounds plus, have 12 inch beam. They are easy to scratch build and sail. Well suited for building by by the novice builder and by the skipper looking for a classic looking model to race.

Wood choices and AMYA rules for Star45 Class

Hulls may be planked using any number of types of wood, including thin aircraft plywood, cedar, balsa, etc.

The Star 45 is a terrific boat for sport sailing and family fun. If you want to race other Star 45's you should build to the AMYA Class rules.

Here are key 2006 AMYA Star 45 Class Rules,section 1.0 Hull:

1.1 The Star 45 Class establishes as their approved plans a set of lines and drawings as the approved reference and construction plans for the class. These plans are scaled and appropriately modified for the use of modelers building a 45-inch model of the Star Boat. Existing plans supplied by kit manufacturers, etc. are grandfathered. New molds, plugs and scratch built models shall conform to the approved plans and specifications.

1.2 Hull length will be 45 inches (plus or minus one half (1/2) inch overall. (NOTE: this does not include any chain plate for backstay attachment, or 1/4 inch bow bumper if used. However, if the chain plate is attached to the transom or overhangs the transom, it may not extend beyond the transom more than 3/8 of a inch.) Hulls may not be less than 11 inches nor exceed 12 inches in beam when measured at the widest point on the deck. (Rubrails are not included in measuring but will not exceed 1/4 inch of thickness/width.)

1.3 In the event of a builder choosing to scratch or hand build a Star 45 Yacht, the builder must adhere to the class approved reference and construction drawings, as obtained from the AMYA Ships Store, as in the builders ability. A second consideration in scratch building is to ensure that safe and sound building practice be maintained.

1.4 All hulls will be constructed of wood or fiberglass or a combination of wood and fiberglass and be a minimum of 16 ounces when weighed before attachment of the deck and keel. This weight must be verified by another member of the Star 45 Class using the Class Measurement Form.

1.5 Decks shall be constructed of wood, fiberglass or plastic laminate material.

1.6 All hulls shall be the standard hard-chine hull. Hulls may be built with a sheer at scale height or with a sheer no more than one inch higher than scale (when measured at the point of maximum depth of sheer.)

1.7 All fiberglass and wood hulls will have a name plate permanently attached to the inside of the hull so as to be seen when the hatch cover is removed.

1.8 At or before its first Sanctioned Regatta the newly built model yacht must be measured using, as reference, the approved measurement form and signed by not less than the owner of the model yacht and one other member of the class. This measurement form shall become, with the registration card, a permanent record of this model yacht.

1.9 The AMYA Star 45 Class recognizes and approves the molds and manufacturer and/or kit packagers of Star 45 molded hulls and kits in existence at the time of approval of these specifications. These sources will be approved sources for the class. New manufacturers will be directed to submit the first of their product to the Class Secretary for approval.

1.10 No maximum weight is specified, however, no yacht will weigh less than 12 pounds when fully rigged ready to sail. This means with all gear, rigging, sails, radio components, batteries and ballast placed and secured on board.

1.11 Bow Bumpers are mandatory for all class registered STAR 45 yachts. Bow bumpers are limited to three eight's of an inch (3/8") overhang. Bow bumpers shall be excluded in the overall length measurement, whether recessed in or otherwise attached to the bow stem. Bow bumpers must be of resilient fabrication to minimize damage to another yacht in the event of a collision.

What is a hull ? and construction categories

Dave Mainwaring's definitions

HULL defintion of:
The outer shell, including frames, ribs, interior bulkheads, exclusive of masts, rigging, deck and equipment.



"bare hull" defintion of:
A model boat's outer shell, EXCLUDING, ribs, interior bulkheads, exclusive of masts, rigging, deck and equipment. Example. A fiberglass hull as pulled from a mold.

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A wooden hull:
one constructed of wood (including plywood).

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A glass hull:
one constructed of reinforced plastic (cloth impregnated with resin). Nominally referred to as a fiberglass hull.

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A composite hull:
a hull constructed of wood and covered with reinforced plastic (cloth impregnated with resin).
OR:
a hull constructed using a laminate (sandwich) consisting of reinforced plastic (cloth impregnated with resin) on two sides of a core . Core materials may be foam or wood.

Star45 sailing model plans

Most browsers will allow you to right click and open the jpg images. You can then save them to your machine.

This set of plans are based on drawing from John Fisher 2006. John may have new and updated drawings available. Check with http://groups.yahoo.com/search?query=star45 membership required.

I want to thank J. Herrmann, www.graphicLanguageOnline.com, for his assistance in converting pdf's to jpg drawing, adding color to the templates and adding the grid to the final images

You can print these drawing to many different sizes.They are not necessarily to scale.

Star45 Hull Templates and shadows

The grid shown is set to 1/4 inch squares. So if you print the templates you can check the size by making sure the grid yields a 1/4 square.

Modelers will use different building materials for the model.These are JPG drawing and print outs may require adjustments to get the widths to correct sizing. For a Star45 AMYA class you need to make adjustments to allow for planking thickness. The rules establish the maximum allowable beam dimension and hull length.

Most browsers will allow you to right click and open the jpg files. You can then save them to your machine.

This set of templates are based on drawing from John Fisher back around August 2006. John may have new and updated drawings available. Check with http://groups.yahoo.com/search?query=star45 membership required.

If you want to scale to use for different model you can change the print out to give you a different grid size.

I want to thank J. Herrmann, www.graphicLanguageOnline.com, for his assistance in converting pdf's to jpg drawing, adding color to the templates and adding the grid to the final images.Rudder templates for a Star45 Class sailing model.The grid shown is set for 1/4 inch squares. So if you print the templates you can check the size by making sure the grid yields a 1/4 inch square.

This set of templates are based on drawing from John Fisher. John may have new and updated drawings available. Check with http://groups.yahoo.com/search?query=star45 membership required.

I want to thank J. Herrmann, www.graphicLanguageOnline.com, for his assistance in converting pdf's to jpg drawing, adding color to the templates and adding the grid to the final images.



These are half shadow that ar eplaced between the templates to add strength to the hull.

Star 45 Construction templates Keel fin

Building templates for S45 Keel fin.
Originals drawings are based on 1/16 ply.

Modeler may want to use different building materials for the fin.
Final keel fin will be shaped the builder. Also these are JPG drawing and print outs may require adjustments to get the templates to correct sizing.

The grid shown is set for 1/4 inch squares. So if you print the templates you can check the size by making sure the grid is a 1/4 square. If you want to scale the keel fins for another model you can change the print out to give you a different grid size.

This set of templates are based on bolt mounting. The grid makes it easy to add to the template to have the keel extend into the hull or extend into the keel bulb. Modeler's choice.

Most browsers will allow you to right click and open the jpg images. You can then save them to your machine.

This set of templates are based on drawing from John Fisher 2006. John may have new and updated drawings available. Check with http://groups.yahoo.com/search?query=star45 membership required.

I want to thank J. Herrmann, www.graphicLanguageOnline.com, for his assistance in converting pdf's to jpg drawing, adding color to the templates and adding the grid to the final images.

S45 Construction templates for laminating rudder

Rudder templates for a Star45 Class sailing model.The grid shown is set for 1/4 inch squares. So if you print the templates you can check the size by making sure the grid yields a 1/4 inch square.

This set of templates are based on drawing from John Fisher. John may have new and updated drawings available. Check with http://groups.yahoo.com/search?query=star45 membership required.

I want to thank J. Herrmann, www.graphicLanguageOnline.com, for his assistance in converting pdf's to jpg drawing, adding color to the templates and adding the grid to the final images.

downloadable files for cutting laser shadows (aka, frames, bulkheads)

Here downloadable files for Star 45 shadows (aka templates, bulkheads). They reside on my site: http://www.mainzone.com/star45frames/.

You can use your browser, go to www.mainzone.com/star45frames/ select the files you want and they will download to your machine. BTW, only the single stringer files are available from Mainzone.com/.
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John Fisher provided the CAD files for laser cutting frames. These frames are trimmed based on 1/16 thick planking.

Contact John Fisher to obtain custom DXF and PDF files and to report any issues with the files. email John racer577 at citystar.com (remove the space between 7 and at, change at to @, and remove the space between at and citystar)
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Most laser plotters used to cut materials require either DXF files or DWG files

DXF files are CAD vector data - plotter files that instruct a device to "start here" then put the (pen, knife) down and "move to, go to"...
Select dxf or dwg based the file type used by your laser cutter.

A CAD viewer or CAD application is required to view the contents. When you download some file types you may see "words" not pictures since these are files with machine commpands.

Builders to do list,

Order Star 45 construction drawing from AMYA store

Buy or borrow books on boat building. Join the Star45 discussion forum.

Decide on type of planking and wood to be used to build the model.

Set aside a work space for building.

Review the bill of materials need to build the model and buy the materials.

Order deck and mast fittings.

Order mast (if you are buying the mast) and order sails (or sail material).

Choose the radio system, buy a sail control unit, Order keel bulb.

While the hull is under construction build:

Keel fin and ballast bulb

Rudder assembly

Make or assemble spars ( mast and booms)

Build cradel to hold boat under construction and when finished.

Test Radio System and sail control unit

After hull is planked:

Install keel trunk or provisions for mounting keel.

Install radio and sail control unit, Then remove while construction continues.

Contstruct deck and hatches

Install/mount deck fittings

Test access to radio and sail control inside the hull.

Provide a exit guide for radio antenna so it can be attached to mast or stays.

Install power switch for turning off batteries

Test mount keel

Paint hull, rudder and keel

Assemble hull, rudder and keel

Set up mast and boom.

Install radio controls.

Check running rigging.

Attach Sails

dry sail model

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Sail
Display
Storage

Sailing Model, AMYA Star45 Class | building board

"John Fisher" is building Star 45's. He has provided a series of photographs taken as he builds the model from scratch.
These are posted to the blog along with his notes to help builders assemble the Star 45.

In the following posts you will find comments, notes. and his photographs

Photo's showing the building board and the first couple of steps for putting the frames together.
Building board is 3" wide 3/4" MDF that is glued/screwed together.

The notched balsa template is glued to the building board using a straight edge. Use a staight edge to make sure it stays straight.

Sailing Model, AMYA Star45 Class | assembling building board jig and setting up frames

Notched balsa is glued to the building board using a straight edge to make sure it stays straight.



The vertical part of the building jig is installed once the stern section is assembled



Key shadows are in placed using notches in building board jig. Midway templates may be placed between these shadows if necessary.



Remember!! Always check your set up dimensions, length, beam, sheer height, against the AMYA plans if you are building a model for the Star45 Class. Your choice of wood and coverings need to be considered as they impact the final dimensions of the completed models.

{AMYA STAR45 hull specifcation 2006}
1.2 Hull length will be 45 inches (plus or minus one half (1/2) inch overall. (NOTE: this does not include any chain plate for backstay attachment, or 1/4 inch bow bumper if used. However, if the chain plate is attached to the transom or overhangs the transom, it may not extend beyond the transom more than 3/8 of a inch.) Hulls may not be less than 11 inches nor exceed 12 inches in beam when measured at the widest point on the deck. (Rubrails are not included in measuring but will not exceed 1/4 inch of thickness/width.)

S45 Construction: a cradle for the hull of wooden Star 45

From Star45 Yahoo Group - Message:
New use for John's Lasercut Frames-"Cradle Making":

Phil Geren needed a cradle for the hull of my woodie Star 45 under construction, to hold the hull while he fair the gunnels to the frames in preparation for installation of the deck and while designing and installing the controls (keel is not on yet).

Well, the easiest way to make a perfect cradle is by using the holes (which are left in the John Fisher lasercut frame sheets after removal of the lasercut frames, to trace the exact shapes of the outsides of frames 2, 4, 6, 8, and 10 onto 3/8' thick plywood. Allow for the thickness of planking and carpeting by drawing a second trace for each frame so that the hole for the hull is 3/8' bigger everywhere than the frame.

Then cut out each second trace as the inside of a frame for a cradle. Mount the cradle frames on a 2'X4' piece of particle board, using the spacing of the balsa template included in the frames kit, and using a try square to get them vertical, and making sure that they are all on the same longitudinal center and all parallel.

Then hot glue 1' wide strips of carpeting to the insides of the cradle frames. Voila! A perfect hull cradle.

Best,
Phil Geren"



















Star45 : Message: The Perfect Cradle: "

Here are the hull cradle fotos I promised you.

Your shadow invention is so useful. The holes left in the plywood sheets after punching out the frames were used as templates to draw perfect frames for a cradle to hold the hull for completion of the construction (before keel installation).

Thanks so much!
Best regards,
Phil Geren"

Sailing Model, AMYA Star45 Class | framing up

Builder's notes:

The vertical part of the jig is installed once the stern section is assembled. These parts keep the shadows sq and vertical.

Adding of the stringers, rails and chine.
For the single chine version, there is only one pc of material for the chine instead of 2 as shown in the photo's.

Remember the 1/8X3/8 spruce for the chain plates. This needs to be installed before the rails go in.

Sailing Model, AMYA Star45 Class | "stringers"

adding the rails. Notice that the rails are made of two pcs. 1/4X1/8 for the first one and then 3/8X1/8 for the second. You need to start both at the transom. Start at the transom with the rails and stringers. Start one side and go forward to station 9 or 10, then do the same on the other side. Then go all the way to the front with one side. Starting both sides at the same time keep the transom from twisting.

Photographs by John Fisher

adding the bottom stringers. 1/8X1/8.

Photo shows the close stringer sanded to fit the side and the back stringer still need to be sanded. John used a sanding block and sand the sides to match the bottom curve. Balsa sands really easy so this is pretty quick. He used 220 grit paper.

Star 45 Construction by : John Whiteford, Rochedale, Queensland, Australia

Following are three Photographs by John Whiteford

Sailing Model, AMYA Star45 Class | Planking bottom of hull

From John Fisher:

Photograph by John Fisher

Photograph by John Fisher

Since it was requested here are a couple of photo's of planking the
bottom of my two wood/glass stars. photo 01 is the bottom of the first
star about half way done. Planks are 1/16 X 3/8 balsa. These were cut
from a 48" long sheet. Weigh your balsa before buying it. I would not
use a 3 X 48 sheet that weighed in at more than 22g. It takes 3 sheets
to cover the bottom and you could add another 1 to 1.5 oz by using
heavy balsa.

I started in the middle and worked to the outside. I sprayed the
shadows with kicker, then put down a plank, then added super fast CA to
hold it down. If the kicker was not dry enough it would cure before it
wicked into the joint which would cause the next plank to not fit
correctly. I had some variation in the planks, but once they were
glassed the bottom smoothed out quite a bit.

If I were to do another one I would add the half frames. I will be
adding them to the DXF files in the next couple of days for anyone
wishing to cut a set.

Picture shows the bottom after it was completely planked. On the
second boat I got a nice pattern on the bottom since the balsa sheets
had different grain structure. I sanded the sided flush and got the
bottom relatively smooth, but not perfect. With the balsa planks they
were flexible and if sanded too much you get thin spots at the frames.
The glass smoothed out inperfections. If doing a hard wood bottom the
planks should fit better than what I did with the balsa.

John Fisher 2006 August 15

Sailing Model, AMYA Star45 Class | bow details - sides planked-- ready for bottom

Star 45 R/C model sail boat | Keels and keel-ballast bulbs

AMYA Star 45 Class Rules, 2006, KEELS AND BALLAST BULBS


7.1 Keel will be of the style known as drop, and will be of the FIN and BULB type.

7.2 Keel fins may be solid or hollow and constructed of reinforced plastic, plastic laminates, fiberglass, wood or metal. (Note: Strength and integrity of the keel fins must be maintained whether built solid or hollow.) Keel fin shape is not specified but must follow the general shapes outlined on the reference drawing. However, keels will not be less than 6 inches nor more than 8 inches long (Fore and Aft) at the keel/hull junction, nor less than 4 inches nor more than 6 inches long (Fore and Aft) at the keel/ballast bulb junction.

7.3 Keels, keel fins and ballast bulbs may be removable, however, they may not be changed, interchanged, substituted or otherwise manipulated once any heat or series of heats in which scores will be compiled, has started. Mechanically movable keels or ballast bulbs are specifically prohibited from use in Star 45 Class Yachts.

7.4 Ballast bulbs may be constructed of any material not prohibited by the AMYA. The actual shape is left to the builder's discretion, but will not exceed 9.75 (9 3/4) inches from the front of the keel bulb to the rearmost point of the keel or bulb.

7.5 Total drop (length) of the keel fin/ballast bulb combination will not exceed 11.5 (11 1/2) inches when measured from the keel/hull junction, before any fillers or streamlining is added.

7.6 Ballast may be made from any readily available material, such as poured lead, lead shot, etc. (Note: When using material such as lead shot, the mass must be solidified through the use of a bonding agent such as fiberglass or epoxy resin, plaster of paris, poured over and through in order to create a solid mass.)

7.7 Race directors may elect to use a template based on the construction plans to determine the keel length (depth).

7.8 Keel depth shall be measured from the center of the keel fin at the hull to the bottom of the ballast bulb. This measurement is from the edge of the bottom of the hull as it meets the side of the keel and should be determined during construction and before any fillet or fairing is added.

7.9 The Star 45 Class specifically excludes radio equipment, sail controls and batteries (power cells) from being considered ballast. This specification defines ballast as anything carried aboard the model for the main purpose of changing the weight distribution of the model and/or weight of the model. Ballast shall be fixed in place by gluing, fiberglassing, or bolting (bolts and screws).

7.9.1 Ballast may not be removed or relocated during any one regatta. The use of Velcro or similar quick release fasteners is prohibited as methods of mounting ballast.

star 45 construction | double diagonal planked hull

From: "John Fisher"

Here are some photo's of Sherwood Jones Star 45 with double diagonal bottom planking. He used two layers of 1/16 planking. The planks are 1" wide. He then covered it with 1 ½oz glass. Weight is about the same as mine with the 1/16 longitudinal planks and two layers of 3.2 oz glass. Just goes to show that there are multiple ways to solve a problem.




John

Sailing Model, AMYA Star45 Class | planking sides

Photo showing adding the side planking and sanding to get ready for bottom planking.
He used 1/16" balsa for my hulls since he will be covering it with glass.

It probably will work the same if you are using harder woods, but you will probably want to trace the outline onto the wood and cut close to shape before gluing it on.

Photo showing side plank after being glued on. John used thin ca and glued the 4" wide plank on.
Make sure it is located correctly before starting gluing.



Photo showing the planks after being trimmed close to the stringers.
John used a # 11 Exacto to trim the balsa planks.
Go slow and take multiple passes here. You don't want to remove too much material or you will get a gap when the bottom is planked. Also trim the rails close at this point.
The rails/side joint will be finished once the hull is taken off the board.

Photo showing the close stringer sanded to fit the side and the back stringer still need to be sanded.
John used a sanding block and sand the sides to match the bottom curve. Balsa sands really easy so this is pretty quick. He used 220 grit paper

Photo showing both hulls with sides matching the bottom curve and ready for planking.

Photo showing the bow sections after sanding and ready for bottom planking.

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http://groups.yahoo.com/group/Star45/ for discussions with other Star 45 sailors.

Sailing Model, AMYA Star45 Class | building rudder

Here are some photo's showing one way to build a rudder quickly and easily. The quick overview is cut out the shape in a thin material, tape the sides together, insert the rudder shaft, fill the inside of the rudder with epoxy. This takes about 10 min or so to do. Followed by installation in your boat.

John Fisher

Lay out the rudder shape on a sheet of 1/64 ply. On other class boats John used a single layer of a 6 oz carbon fiber layup, so you could also lay up some fiberglass for use on the star. To do a glass layup, just take a sheet of 6 oz or heavier fiberglass, a sheet of lexan or plexiglass, and some resin. The first step is to spread resin on the plexiglass, then apply the fiberglass and then make sure it is all wetted out. Once cure flex the plexiglass and the layup will pop off.

Shows the two sides cut out of plywood, these could be fiberglass instead. Straight sided shapes like shown and the star plans are easier to make.

Tape the two sides together with masking tape. With curved shapes He taped them together then insert the shaft and resin. If you use straight sides on the rudder you can tape one side and then open it up like a book, apply resin, then close and tape shut. The open book method uses less resin but only works with sq or straight sided shapes.

Note the bend John put in the shaft to prevent it from turning inside the rudder.

Shows the top open to pour in resin. John uses a syringe to pour in resin once the shaft is in place. You can add micro balloons to the resin if concerned about weight.



Installing Rudder in Star 45

John Fisher photographer

Star 45 Rudder Construction, using laser cut laminations

Star45 : Message: Re: [Star45] naca0009 rudder: "Re: [Star45] Photo's of naca0009 rudder

I am happy with how they turned out. I sent the production files to Stevens Monday, so you should be able to order a rudder if you need one. He doesn't have it posted yet, but if you call him he can cut them for you.
I built mine by clamping all the pcs together with the alignment pins in place (1/8 sq stock left over from stringers). Then CA'd it together with thin CA. I used my random orbital sander with 150 grit to shape it. Took about 15 min or so. With the different layers you can see if you are removing material evenly. Once sanded I sprayed the rudder with 3M 77, covered with 3 oz glass, one PC folding it over the leading edge so there is no seam on the leading edge. I then added resin and vac bagged in my handy food saver. The next day I pulled off the breather and peel ply, sanded smooth and varnished.

The glass is probably not needed since the core is made out of ply. I used the glass to ensure it is not coming apart and only adds another 10 min or so to do. With the vac bagging it is very smooth and uniform with only a little sanding required to remove the texture of the peel ply. I did buy a yard of breather and peel ply, but waxed paper with holes in it and paper towels can be substituted."

Drawings are available from the Yahoo Star45 group "files"

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Sailing Model, AMYA Star45 Class | Rudder

AMYA Star 45 Class Rules, 2006, Rudder

6.1 Rudders may be constructed of wood, fiberglass, plastic, plastic laminates or metal. The exact shape is not specified, but they may not exceed 4 1/2 inches at the hull (fore and aft) 3 inches at the bottom, (fore and aft); and may not project more than 7 inches below the hull when measured at the post..

Star 45 Construction Planking with edge glueing

[Star45] Update on planking bottom with edge glueing.

John Fisher is ready { 4/19/2007 } to glass his latest boat and is sharing how he planked it. His dad built a ply sided, cedar planked star using titebond II and it came out pretty light and stiff. With this information I started to build another hull using the same materials. He felt that edge gluing the planks added a lot of the strength to his boat. John didn't want to glue in extra wood to hold the pins to keep the planks in place for the glue to dry, so I combined two methods of planking. John liked the quickness of planking with CA and kicker, but it lacked stiffness when sanding the bottom before glassing. So he decided to edge glue the planks and then tack them in place to the frames with CA.

In this photo you can see where John put drops of CA on the planks. The wood is slightly darker.


It worked well. John has an edge glued bottom and he was able to plank it in one evening. To do this John first spray the frames with kicker, then apply titebond III to the edge of the planks. He then would hold the plank in place, tight against the previous plank, and apply a drop of CA to each frame to hold it in place. It did not matter where John started, bow, stern, or middle, but do make sure the CA has set up before moving to the next frame. Once the whole plank was in place he came back and wiped off the extra titebond. To fair the bottom to the sides he used a $10, 6" plane from home depot set at .010" depth of cut. It quickly removed the cedar and a little sanding finished the job.

John had one plank that was too thin that he had to remove, it was harder than expected. He had the use quite a bit of force to break the glue joint at each frame, so he is confident that this method is strong. John will also use this for balsa planked bottoms.

In photo # 10 you can see the stern still needs to be trimmed and sanded. John will probably use a saw to trim in close and then sand to fair it.

S45 Construction | hull: double diagonal planking

From: "John Fisher"

Here are some photo's of Sherwood Jones Star 45 with double diagonal bottom planking. He used two layers of 1/16 planking. The planks are 1" wide. He then covered it with 1 ½oz glass. Weight is about the same as mine with the 1/16 longitudinal planks and two layers of 3.2 oz glass. Just goes to show that there are multiple ways to solve a problem.



John

Sailing Model, AMYA Star45 Class | transom details

View of Transom construction.

Star 45 "Mainwaring keel and bulb" on an old S45

Sailing Model, AMYA Star45 Class | keel mount - using keel trunk

Here is how John Fisher built two Star45 keel trunks. First he make a aluminum mandrel that is the same size and shape of the top of his keels. Next he waxed the aluminum and then put a single layer of wax paper over the mandrel.

He used a light spray of 3M 77 to stick the ends together on the second one. The first one had a pc of tape, which is now a part of the trunk.

The mandrel with waxed paper is wrapped with glass which he again used 3M 77 to hold in place. He has not verified that this doesnt have any long term effects to the glass so use at your own risk. John used 2 layers 3.2 oz glass with glass tape on the top and bottom edges to help add some stregth. Usually he would add kevlar, but that is not allowed in the star's. One the glass was in place John wet the whole thing with resin. If you dont have any way to vac bag the trunk, just let it cure and remove the mandrel. The trunk weighted in at 1 oz.

John has a food vacuum sealer so he put a release paper over the top (wax paper with holes in it), then breather cloth (he hasused paper towels in the past), and then into a food saver bag for the night.

To remove the mandrel he used a hammer and a vice. He knows that sounds severe, but that is what it took to get the mandrel back out. He started by placing the mandrel into a vice with smooth jaws. The jaws were just far enough apart that the aluminum would fit between them, but not the fiber glass wrap. Then he tapped the mandrel out. He points out how much force it took for him to get this apart so you can design your keel top with this in mind.

Photo 01- mandrel before prep
Photo 03 -mandrel with glass, ready for resin
Photo 04-keel trunk in food saver bag. You can see the resin going into the breather cloth.
Photo 05 - keel trunk off the mandrel, note the tape. 2nd trunk used3M 77 instead.
Photo 06 - Trunk on the keel.





The following picture shows the way that John aligned the keel on his second boat.
Since the keel is plate and 1/8" thick I laid a straight edge on it and
aligned it with the pc at the center of the transom. I did this on both
sides to make sure it is centered as well.

To capture the top of the keel box he added 2 1/8" X 3/8" spruce blocks
to the top of the keel trunk and glued them to the king plank. The photo also shows the glass tape He used to reinforce the
radio tray.

John Fisher photographer

===

here is an alternative keel trunk (from Uncle Dave)

I poked my camera down into the Sirius 45 and snapped a couple of pictures showing how the keel is attached to allow it to be removed and another installed.

The keel is a aluminum fin with my flat bottomed bulb. The keel trunk is assembled over the keel fin before mounting the trunk in the hull. The trunk is pretty simple. Two pieces of 1/8 ply on either side of the fin. Cut flush across the top of the fin. Height is determined by the amount of the fin to extend into the hull. Length is determined by the shadows or braces to support the fin. A filler pieced goes between the sides so that fin can be slid own and out of the trunk.

Before gluing the trunk up it is very important to coat the insides of the trunk to make the sides of the trunk as water resistant as you can. The the fun part is placing two mounting bolts through the sides of the trunk and thought the keel fin. I think the two bolts in the picture were 1/2 long 3/8 inch dia.



I placed a heavy wire through the both the bolt heads so I could turn the nuts on the other side.



With the nuts removed the two bolts simply push to one side and the keel fin mounted or removed as the case may be. In my models the height of the fin inside the model is low enough for a swing arm sail control to fit properly. I use Probar (now Dumas) SCU's.

Before building the deck I simply dropped the trunk (with keel fin) through the slot in the bottom of the hull so the trunk rests on the keelson. The hull being fiberglass the trunk if filleted with the bottom using some auto body resin-paste. I think I also used the resin paste to mount the keel trunk in my wooden models (memory escapes me its been years). The ends of the trunk are braced to the chine to with stand leverage forces from the heavy keel bulb and sailing stresses.



When the two bolts are tightened they not only hold the keel in place they also pull the sides of the of the trunk tightly together. With the tight fit one should expect the keel fin may stick in the trunk if some sort of lubricant (silicone) isn't used.

Sailing Model, AMYA Star45 Class | interior work, radio, sail controls, servos, mast support

Radio Board stringers between bulkheads

(Note the method of keel support using these stringers)



Radio Board



Rudder Servo



Mast support (inside hull)

S45 Construction | John Fisher -- keel tubes

Photo sequence showing how John Fisher made his keel tubes. He was mounting a keel from CPM (David Ramos) with longer keel bolts so they will go through the deck when finished. He coated the brass rod with carnuba wax as a mold release.

To align the keel tubes John drills the holes in the center of the boat, this is easy to find since it is simply the middle of the king plank and the middle of the two keel planks. Then to align them so they are straight he placed a metal ruler along the two keel bolts or if a flat plate along the plate. Then look at where the end meets the transom. It should be off center by half the amount as the bolts/keel are thick. John does this on both sides to make sure it is centered. Once the bottom is aligned he tacks it in place with CA, then verify the alignment at the deck the same way.

Star45 Construction "Mast -Jack" from John Fisher

John Fisher's mast jack is pretty simple. He made a fitting that went in the bottom of the mast that was threaded 8-32. Then he cut down a brass nut from Lowe's and soldered it to a 8-32 bolt. This fits into the mast step and threads into the bottom of the mast. Recommends you add a jam nut since the rig seemed to slowly lose tension as model sailed. The lock nut will be another cut down brass nut or a pc of 1/16 aluminum that is threaded 8-32.

John's parts are pretty fancy and without a lathe and CNC mill would be hard to make. The quick and easy way to make the same parts is to glue a wood block into the bottom of the mast, then use a blind nut as the thread for the mast jack. JB weld bonds well to aluminum and I would recommend it for gluing in the wood block.

For rig adjustment set the shrouds just tight enough that you have to undo the jib from the deck to move the rig. Get the shrouds set to have the mast straight, then put it in the right position for the wind speed, then add tension by unscrewing the mast jack. By having the rig set up this way you do not need to adjust your shrouds when moving the rig fore or aft or to change the tension in the forestay.

Star 45 Keel fins building options, Star45

{Rule7.2}
Keel fins may be solid or hollow and constructed of reinforced plastic, plastic laminates, fiberglass, wood or metal. (Note: Strength and integrity of the keel fins must be maintained whether built solid or hollow.) Keel fin shape is not specified but must follow the general shapes outlined on the reference drawing. However, keels will not be less than 6 inches nor more than 8 inches long (Fore and Aft) at the keel/hull junction, nor less than 4 inches nor more than 6 inches long (Fore and Aft) at the keel/ballast bulb junction.

--
The Mainwaring Keel shape is a fine choice!
--

John Fisher suggests:

The quickest and easiest way to make them if you have access to a metal band saw is to draw the keel in CAD, then print it out. Glue that to a sheet of 3/32 aluminum with 3m77 and cut it to shape.

You could also do the same thing with sheets of plywood and layer it to achive a airfoil shape. Each layer should be smaller than the last and then sand to blend the layers. Could also make a good cad project.

Another way is to cut the shape in two pcs of 1/16 ply, then tape the edges together. Insert a couple of threaded rods between the two sheets for attachment. Then fill with epoxy and microballoons. Using this method you should also glass the outside for additional stiffness. There are photo's of making a rudder like this on the blog site.

--

S45 Model Boat construction | Sail Control Units

installing the radio tray for an under deck winch, jib tweaker, and rudder servo. From John Fisher:



The radio tray is 1/16 ply backed up with 1/8 X 3/8 spruce or basswood. Note the glassing at the ends. This adds a lot of strength to the joint and John highly recommend adding it. John uses 1" wide glass tape cut in half, then sprayed with 3M77 so it will stay in place for gluing. Then a dab of your favorite epoxy and you are done.






sheet through deck mount.


jib tweaker turn around. The part is a 180 deg sheet lead from great basin.



See also http://woodstar45.blogspot.com/2006/10/blog-post_116031550255831231.html
--
From: David Ramos To: Star45@yahoogroups.com
Sent: Fri, 14 Nov 2008 10:23 am
The following photos show my set up for a drum servo and jib tweaker.

--
Note:
One major advantage of building from a fiberglass hull is the open space inside the hull. David Ramos offers workmanship second to none.

Dave Mainwaring
--
http://www.rcyachts.com/STAR45/P1010084.JPG


http://www.rcyachts.com/STAR45/P1010082.JPG


Main sheet is 2:1 and jib sheet is 1:1

Hope this helps
David Ramos
Chesapeake Performance Models
227 Main Street
Stevensville, MD 21666
david@rcyachts.com
www.rcyachts.com

A Drum style model sail winch

photo's courtesy of "Larry Ludwig" at www.LudwigRCYachts.com, Ludwig Mfg.

==

From: "Stephen Pratt" :

"On the North Coast (Ohio), are using HiTec HS-725 or HS-785 Winches. Bob Luther developed a mechanism to work an endless loop system of sail control. Fits inside the Star 45 with plenty room to spare."

a simple Jib-Twitcher for swapping jib down wind

Sailing Model, AMYA Star45 Class | Masts

3.1 Masts shall be made of wood or aluminum. Swing rigs, rotating and permanently bent masts are prohibited.

3.2 Masts shall not exceed 3/4 inches square when measured at the thickest point of the mast. Maximum mast height shall be 70" when measured from the deck, inclusive of the crane. Rotating wind indicators and burgee staffs are not included provided the backstay is not attached to them in order to circumvent the 70" maximum mast height specification.

Typical Slotted Aluminum Masts for model sail boat

photo's courtesy of "Larry Ludwig" at www.LudwigRCYachts.com, Ludwig Mfg.

Sailing Model, AMYA Star45 Class | Booms

AMYA Star 45 Class Rules, 2006, Boom
4.0 BOOMS:

4.1 The main boom and jib club shall not exceed 5/8" when measured at the thickest point. Booms and jib clubs shall be constructed of wood, aluminum and/or fiberglass.

Some typical Fittings for sailing model

photo's courtesy of "Larry Ludwig" at www.LudwigRCYachts.com, Ludwig Mfg.

==

A simple and light weight plywood strut made from scrap 1/32 or 1/16 ply.

A sample of one builder's standing rigging fittings bill of materials

Sources:
http://gbmy.com/
http://www.worthmarine.com/

Main Boom kit #100L
Jib boom kit #102
Gooseneck/kicking strap #112
Head fitting #120
Turnbuckle (2 pk) #260 Need 4 total
Tangs (4 pk) #282 4 is all you need
Bowsies(10 pk) #199
KDH single block #250 Two each
Sheet Hooks (20 pk) #280

Of course there’s many things that can be substituted.

Instead of wooden or arrow shaft booms, airplane clips instead of the turnbuckles and so on.

From: "Robert Gonzalez"
Subject: Re: Rig Parts for Star 45
Date: Tuesday, June 05, 2001 1:17 PM

I ordered both size head cranes - I think the smaller one is ok, but I'm not
sure. Woody has one and is bent more at 90 degrees since according to the rules
the crane is included in the 70" mast height.

I also ordered the 1/2" mast head and foot inserts. They don't fit the new masts without being sanded down some.

I wasn't sure what I wanted to do for an adjustable foot. I ordered the Sail Etc
deck track and adjustable mount. Mine has popped out on Woody more than once.
Don (at Great Basin) doesn't offer many choices for these parts.

I need some more Pekabe fairleads if I run the rigging under the deck and if not
then Woody has three blocks on deck - using the bungee method.

I got the side stay racks this time and the jib rack - not sure I'll use them or
not.

Quick release turnbuckles are nice. At $10 ea - they're kind of high dollar
but easy to use. Don>>the KDH quick release turnbuckles are 2 to a package for 10.90.

Main Booms, Goosenecks, and Vangs,

The main boom of a model is linked to the mast by a swivel connector which allows the boom to swing from side to side.


Typically the boom on a model needs to kept from lifting when the sails are not trimmed in hard.

To keep the main boom from flying up a "boom vang" kicker a simple device is set between the boom and the foot of the mast. Vangs take a variety of forms from a trunbuckle, to a piece of fishing line to a line controlled by a servo to allow the boom to be pulled down or allowed to raise up.

Jib booms, radial jib fittings and vangs

The mainsail and jib on the Star 45 are self tending. That is they can swing from side to side as the model tacks without requiring the sheets to be tended.

Originally on the old model the jib was loose footed and did not use a jib boom (aka a jib club). The addition of a jib club allowed the jib shape to be controlled.

Like the main sail the foot of the jib will fly up is some type of vang is not in place. Typically a swivel is placed along the forward end of the jib boom and clipped to a deck fitting (aka jib rack).

Look at the jib as a triangle. The halyard pulling the head of the jib places a force on the jib swivel. As the swivel is moved forward and aft along the jib boom the leach of the sail has more or less ability to rise. The head of the jib also moves off center.

It is possible to find jib boom fittings that anchor the forward end of the jib to the bow and use a vang to control the lift of the boom. These are known as radial jib fittings. The jib stay attaches to the radial fitting. This has the advantage of staying taught against the back stay as the sails are trimmed,

The jib boom and swivel also pull against the back stay. Since the jib stay attached to the jib boom in this arrangement moves off center and is subject to varying wind forces the tension on the jib stay and back stay will vary.

The driving force of the sails is changed when the slot between the mast and jib changes. Finding the best spot for the mast and jib swivel/radial fitting adds the challange of setting up the sails prior to sailing.

Star 45 Model Sailboat, GET THAT TOPPING LIFT RIGHT (if you wanna go fast)!

By Phil Geren

Of all the go fast stuff I have learned from tuning experts over the past year, the most valuable, and the thing that has provided the most additional boat speed for my 13#-3.5oz Star 45 (the "Fat Lady") is how to get the Jib's topping lift set right. I am doing much better in my racing since learning this.

The curve of the leech of the Jibsail MUST resemble as closely as possible the curve of the leeward surface of the Mainsail when sighting from the foredeck. If the Jib's leech is flatter or fuller your boat will not attain its speed potential while beating and reaching.

The topping lift enables you to get the curves aligned. Tightening the topping lift makes the Jib's leech fuller, more curved. Loosening the topping lift makes the Jib's leech flatter. With a little practice you can get the curves to be identical.

Here's how:

Pull the Mainsail in to the beating position; Swivel the Jib boom with your finger (apply only lateral force, no upward or downward force on the Jib boom) so that when you sight from the foredeck and look up and down the curve of the windward surface of the leech of the Jibsail it is superimposed on the curve of the back (leeward) surface of the Mainsail.

Are the curves identical? If not, is the Jib's leech more curved?
If it is, loosen the topping lift.

If the Jib's leech is flatter, tighten the topping lift.

Make small adjustments. This is very sensitive, and you can get it right if you persevere.
Recheck the need for adjustment after every few heats of racing or if you change anything else.

On sailboats EVERYTHING is related to everything else, and you will need to readjust periodically to maintain your added speed.

Don't have a topping lift? INSTALL ONE NOW! You won't believe the improvement!

Construction Star 45, Sail Making, colored sails, sail material

Apr 2007 Subject: [Star45] Sails - colors
--
From: "Larry Ludwig" mailing list Star45@yahoogroups.com

You can have colored sails. You can make your own from ripstop and the colors are all available. The material is inexpensive enough that even if you do botch the first few attempts it's not going to set you back more than $10.00

Learning to make sails teachs you more about TRIMMING sails and the way they take a "set" than sailing a boat ever will.

If you set your mainsail luff as a bolt rope (and you should IMHO) then it takes only a few seconds to pop off your mast head or foot, slide out one sail and slide in the other. Then if your jib is setup as a hook attachment to a hole in the mast, you unhook from the deck, unhook from the mast and voila, you are ready to hook both ends of the 2nd sail and you are complete. You should be able to change the sails on your boat in 2 minutes if you are properly set up. Of course, using a 2nd mast and complete rig is even faster. If you setup so your turnbuckles remain on the deck, then they are ready to go regardless of which rig you chose, and you reduce the cost of a 2nd rig by $40 right there.

Don't discount ripstop sails too much. They may not be all the rage... but I promise you the skipper skill factor is WAY more important than the sail material. I have rip stop sails here that have lasted 20 years, if they are well cared for, they will last. Skippers familiar with the Vic class will remember a Regional Regatta being won with a stock ripstop mainsail last year ( I think it was)

Give it a shot, you won't be sorry you did. *and it DOES look very nice on your boat.
--
From: "J Fisher" Sender: Star45@yahoogroups.com Subject: Re: [Star45] Sails - colors

I have seen people in the 914 fleet use colored markers to color sails. I think it was mostly to tell the boats apart, but there were some interesting designs. You could probably paint your sails as well to get color.
--
From: jfisher@wildblue.net I have made a lot of sail and could put together a step by step to make sails.

I use mylar which I buy from www.McMaster.com. They only carry clear, so I sand it to make it translucent. It colors well with markers so that would be one way to make colored sails. To make sails you can use the sail block based on the method provided on the star 45 yahoo groups by John Whitford or you can use the block from great basin, which is based on the Sweede Johnson sail block. I have used the sweede block with good results.
--
From: "Larry Ludwig" Sender: Star45@yahoogroups.com Subject: RE: [Star45] Sails - colors

You can make panelled sails, but it is not required. You can get PLENTY of use out of a single panelled sail. They actually have some advantages in high winds because of the less draught. Also, but putting in the luff curve and using a bolt-rope main, you do have a sail with some draught to it, not just a flat sheet of cloth. The block method works fine, but also.. is not required. Basically you cut the bottom panel seam flat, and draw your airfoil MAC (mean aerodynamic chord) and cut it with a #9 X-acto or scissors. Use seamstress tape and overstitch. Do the same thing with the luff curve, and hem the foot and leech and you are about there. Oversew some corner panels, tack on some batten pockets and thread in a piece of weed-eater line up the hem of the luff and you are ready to put on your class markings and numbers. Grommets in the corners are installed either with a seamstress tool or they could be ordered from Don Ginther at GBMY if he is still shipping, he was in the process of suspending operations.

Where to find the material? Nylon ripstop is inexpensive... typically $6-$7 (x 38-50" long bolt) a yard at LONDON's Fabrics or HANCOCK Fabrics, sometimes you will find it at HOBBY LOBBY retail stores, but if you check your local fabric store you will most likely come up with some in various colors. Also using contrasting thread colors can make the sail more attractive. Start with a single panel sail and go through all the steps. When you are ready to start making paneled sails... don't be afraid to make them out of paper first. Typical brown paper can be cut and taped together and makes a perfect mock up of the sail for pennies.
--
From: "Al Stein" Sender: Star45@yahoogroups.com Subject: [Star45] Re: Sails - colors

I think I got mine from Potomac Sailmakers in Alexandria, Virginia... I bought yellow and orange, but they had a bunch of different colors in spinnaker cloth, and very light weight and airtight it is.

It's fairly stiff, too, for as light as it is -- something well under an ounce per yard. Price about the same as Larry experienced... less than $10 a running yard from a BIG WIDE bolt (can't remenber exact width, but it was much wider than normal fabric store goods.
--
From: "John & Kelly" Sender: Star45@yahoogroups.com Subject: RE: [Star45] Sails - colors

I have built US One Meter sails from spinnaker cloth purchased from Sailrite.

I used .5 oz which is only available in red, white, and blue, but .75 oz is available in a multitude of colors.

The part I like best about these materials is you can buy a role of C3 spinnaker tape (pricey at $25.00) and build a set of sails without sewing a stitch.

They actually use C3 to tape together the body seams of full scale spinnakers so I'm pretty sure it can take just about anything a model can throw at it.

I've built two sets of sails and only used about 10% of my role of tape so that $25.00 will go a long way.

At about $12.00 a yard, spinnaker cloth is twice the cost of fabric store ripstop, but spinnaker cloth is coated with resin that makes it far more stable and eliminates all porosity (wind can blow right through ripstop). I also haven't tried using C3 on plain ripstop, so I can't say how the bond will hold up.

For cutting fabric like this I'd use a hot knife. I bought a $4.00 40watt soldering iron at the local mega-mart, removed the tip, hammered it flat, and put it back in. Cutting works best over a smooth heat resistant surface. I use my glass topped kitchen table (when my wife's not home).
--

Sails for AMYA Star 45 Sailing Model

AMYA Star 45 Class Rules, 2006, Sails

2.1 Sails may be of single or multi-paneled construction. Sail material shall be unrestricted.

2.2 All sails are to be cut to comply with the following maximum dimensions when measured by the procedure as outlined in the "AMYA Regulations". Dimensions shown are measured 'Edge of Cloth" to "Edge of Cloth" and are in inches.

2.3
MAIN JIB
Luff 62.75 42.50
Foot 25.50 15.75
Leech 65.50 37.00
Roach 2.00 0.50
Head 0.75 0.75
Foot Round 0.50 0.50

2.4 All sails, main and jib, will be cut with either a straight head to clew leech with no roach, or a fair
curved head to clew leech with the maximum roach point occurring approximately one half the distance from the clew to head. Divide a straight line from the aft corners of the Clew and Head into four (4) equal sections. Then, for the Main Sail, maximum offset from edge of cloth for the Roach at the quarter points to be 1.75" and the offset at the mid-point to be 2.0". For the Jib, the offset at the quarter points to be 0.375" and at the mid-point to be 0.50". Sails cut with a straight leech at the maximum roach allowance are prohibited from use on the Star 45 Class Yacht.

2.5 The mainsail gooseneck or attachment will be attached to the Mast between 0.50 inch minimum to 4.0 inch maximum measured from the deck.

2.6 Battens are allowed on the mainsail but are restricted to 4 in number, equally spaced along the leech and may not exceed 8.50 inches in length. Battens are not permitted in the jib sail.

2.7 Sailmakers must conform to the above measurements.

9.1 Each yacht shall carry on her main sail the class 5 point "STAR EMBLEM" and an assigned AMYA registration number. The star shall be at least 2 inches in size (measured from point to point across the flat of the star) and positioned above the registration number. Registration numbers shall be at least 3 inches in height and at least 3/8 inch thick. Both star and registration numbers will be placed on the upper half of the mainsail on both port and starboard sides of the mainsail and shall be positioned so as to be easily read from either side.

Star 45 Construction | Class rules regarding Keels

Class specifications as of 2006:

7.0 KEELS AND BALLAST BULBS:

7.1 Keel will be of the style known as drop, and will be of the FIN and BULB type.

7.2 Keel fins may be solid or hollow and constructed of reinforced plastic, plastic laminates, fiberglass, wood or metal. (Note: Strength and integrity of the keel fins must be maintained whether built solid or hollow.) Keel fin shape is not specified but must follow the general shapes outlined on the reference drawing. However, keels will not be less than 6 inches nor more than 8 inches long (Fore and Aft) at the keel/hull junction, nor less than 4 inches nor more than 6 inches long (Fore and
Aft) at the keel/ballast bulb junction.

7.3 Keels, keel fins and ballast bulbs may be removable, however, they may not be changed, interchanged, substituted or otherwise manipulated once any heat or series of heats in which scores will be compiled, has started. Mechanically movable keels or ballast bulbs are specifically prohibited from use in Star 45 Class Yachts.

7.4 Ballast bulbs may be constructed of any material not prohibited by the AMYA. The actual shape is left to the builder's discretion, but will not exceed 9.75 (9 3/4) inches from the front of the keel bulb to the rearmost point of the keel or bulb.

7.5 Total drop (length) of the keel fin/ballast bulb combination will not exceed 11.5 (11 1/2) inches when measured from the keel/hull junction, before any fillers or streamlining is added.

7.6 Ballast may be made from any readily available material, such as poured lead, lead shot, etc. (Note: When using material such as lead shot, the mass must be solidified through the use of a bonding agent such as fiberglass or epoxy resin, plaster of paris, poured over and through in order to create a solid mass.)

7.7 Race directors may elect to use a template based on the construction plans to determine the keel length (depth).

7.8 Keel depth shall be measured from the center of the keel fin at the hull to the bottom of the ballast bulb. This measurement is from the edge of the bottom of the hull as it meets the side of the keel and should be determined during construction and before any fillet or fairing is added.

7.9 The Star 45 Class specifically excludes radio equipment, sail controls and batteries (power cells) from being considered ballast. This specification defines ballast as anything carried aboard the model for the main purpose of changing the weight distribution of the model and/or weight of the model. Ballast shall be fixed in place by gluing, fiberglassing, or bolting (bolts and screws).

7.9.1 Ballast may not be removed or relocated during any one regatta. The use of Velcro or similar quick release fasteners is prohibited as methods of mounting ballast.

Sailing model boat | making your own keel bulb

From: "Jim Adams"

I made a plug from balsa and finished it to a smooth finish.
Using two aluminum pans (the kind that you throw away). Fill the first one with plaster took the balsa-bulb (well waxed) and placed it in the plaster half way in. I used two pins through the center to hold it down.

Let the plaster harden, then pull out the balsa-plug. Next put thin saran wrap over the mold and place the balsa-plug back in the mold. Now comes the fun part I used rubber bands to hold the plug in place (remember I had two pins that extend past the mold walls). Fill the second pan with plaster and lay the first on top, it is kind of messy but it works. When the second half hardens (about two hours) pull them apart. You will need to plug the holes at the ends on the sides and create small air path upward in the and a spur (looks like a funnel when you are done this needs to be big enough to pour in the lead) at the end.

==
Pouring molten lead is dangerous. The plaster mold which Jim Describes must be absoultely dry and free of moisture or the lead can spray out ot the spur.

Sailing Model, AMYA Star45 Class | Decking

From Terry Forbes:
"The Star 45 boats that I have built have decks made from bass wood strips that are 1/4" X 1/16". I find them easy to use and easy to bend with out fracturing. I use thick ca to bond to hull frames and to the adjoining strip. When is have it all glued down, I sand with 120 grit and then 200. I use a soft rag to wipe off deck but leave the cracks filled with the sanding dust or "wood Flower" I then give it a thinned coat of slow cure epoxy. This first coat will soak into the wood completely. I then use un-thinned epoxy for the second and third coat, wet sanding and tack ragging between coats. If you want a really glassy deck, I use a finish coat of Captians Spar varnish. I have used this finish technique on full scale boats and all of my Kayaks. Very nice and durable finish. The decks go on easy and I try to stagger the strips one dark one light. I built a full scale star in the early 60's and had a striped planked deck. I like the look and it builds light. It keeps the hull true as sometimes when you add the deck using plywood it can cause it to move around. I will post some photos of my next hull as it comes to life. I have constructed a ships-way. I used the formers that are shown on the IMYA star plans. I now only have to cut the actual hull formers. I Stack cut 4 at a time on my trusty Dremmel Moto Shop Saw. I have added some lighting holes here and there. All in all I can have a hull lofted in 1 hr. and the sides on that evening using 20-min epoxy to coat the frames and the inside of the hull side. I first made my side peaces out of poster board. This allowed me to get the fit close and have a template to trace the sides for cutting. "

S45 Construction Deck

4/19/2007 John Fisher just finished the deck rigging last night on his latest boat. The boat is set up pretty simple. Open loop with elastic. Winch is below deck, but the same rigging setup can be used with an on deck winch, just substitute a turning block for the through deck block.

The sheets go forward to a block on a bridle for the main sheet. The jib sheet and elastic go through a double block attached to the chain plate to keep things from rubbing on the mast, then through an adjustable double block forward. The jib sheet then goes back to a deck mounted block. The elastic is then hooked to a loop on deck. John put a hook in the elastic so he can release tension when in storage.

Chain plates and mast step are laid out per Scott Rowlands tuning guide.





In tweaker photo bellow you can see the tweaker servo and winch mount.

Sailing Model, AMYA Star45 Class | Construction Deck(s), Hatches

from John Fisher:
Attaching deck to hull

John Fisher photographer

Hull with deck mounted:

John Fisher photographer

--------------------

HATCHES:

From Phil Geren:
The simplest hatch cover solution I have found for Star 45 is to cut a piece out of Presentation Cover vinyl, which cut-out is shaped like the hatch opening but 1/4 or 3/8 of an inch larger on all sides. Then, apply electrician's tape (1/2 or 3/4" wide) all around the perifery, so that half the tape is on the vinyl and half is hanging over the edge.

Presentation Cover vinyl which I get at Office Depot is about 15 cents a sheet; it is about 0.008" thick; it is slightly over 8.5X11" in size; a full sheet weighs about 16 grams; it is stiff, but flexible; it is crystal clear, but if you want it opaque, just wet sand it with #400 grit wet or dry sandpaper.

Position the hatch cover over the hatch so that the tape extends evenly past the hatch opening an equal distance all around, and then just press on the tape to stick it to the deck. It's waterproof, durable.

You can make spares and stick them to another piece of vinyl and carry that with you to the races. That keeps spares nice and flat and keeps the tape's sticky side clean for future use. A set of these hatch covers usually lasts me all season. At lunch, I take one cover off to allow the boat to dry out, sticking the cover to a dry vinyl sheet to keep the tape's sticky side clean.

Photo is Star 45 #778, freshly rebuilt for the Nationals this year, and a set of covers on the floor next to her.

Phil Geren photographer

--
from Uncle Dave:
I pulled one of my old Star45's from the attic and have it here in my workshop. It has a fiberglass Sirius 45 hull, a aircraft ply deck and aluminum keel fin. Unfortunately it is not one of my finest examples of workmanship or painting. However I'll suffer the embarrassment and use if to show some one style of hatch construction.

Carrying around a model around out of the water is no big deal. Taking a model out of the water can be something else. You first need to hang onto the model. Then find a place to take hold to lift the model. This is one of the reasons I have used easily removable hatches. You can grab the model through the hatch, fingers under the deck and pick it up. Of course a thin ply deck the model deck and hatch construction needs to be strong enough to withstand pulling on the deck and lifting a twelve pound plus model. Therefore I braced my decks around hatch areas.

First I built a flanged frame for the hatch to sit in that also extended under the deck and attached to the deck bracing.


Then I built a hatch cover based on the size of the hatch. Initially the hatch cover was made to fit very loosely in the hatch. I then took some silicone (tub seal or similar) squeezed a bead around the shelf/lip of the hatch. The covering the hatch opening with food wrap poly sheeting I'd push the hatch cover in place down into the silicone. This made a nice water tight gasket around the edge of the hatch. After waiting a day I'd remove the plastic, trim and silicone that showed topside. With the silicone dry, pop the hatch cover in place and check the fit.



I placed a strip of magnetic tape on either end of the cover and on each end of the hatch frame.



When the hatch cover and hatch mag tapes touched they pulled together. This magnetic tape is neat stuff you can pop the cover in place and it will stay put.

Typically I made my hatches about 4"X5" giving me plenty of deck to the sheer.


I heavy weather if the model might go over on beams end I'd cover the seams with tape just to be extra watertight. A 4X5 hatch gives room to get inside, adjust winch, radio etc, and to remove any water that got into the bilge while sailing.

Curved mast -- tuning a mainsail

From: Philgeren@aol.com
Sender: Star45@yahoogroups.com
Date: Wed, 22 Nov 2006 06:58:53 EST
Subject: Re: [Star45] Curved mast -- advantage ??


Curving a mast so that it bends convex forward (concave aft) moves the luff edge of the sail forward and reduces the camber of the sail in the section where the mast is bent (if bent half way up the mast, the camber in the up/down center of the luff of the sail is reduced). In a blow, this reduces power, reduces leeway force, reduces weather helm, allows the boat to increase its speed.

Generally, the minimum position of mast bend is considered to be a curve equal to the luff curve designed into the luff edge of the mainsail. For very light air and for heavy air, maximum mast bend is used for maximum speed. For very light air, less camber makes it easier for air to stay attached to the leeward surface of the mainsail as the air passes aft. For medium air and for waves, where maximum power equates to maximum speed, minimum mast bend is used to get maximum designed camber.


By use of all the tuning controls on a mainsail, one can obtain a certain amount of control over the distribution of camber over the length of the mast, and there will be an optimum camber distribution for any particular sail and set of wind conditions. Pretty complicated to get it perfect, however outstanding sailors like Stuart Walker are on record as saying it is of paramount importance to use this against competitors who are using it. Otherwise, in a one-design competition they win.
My two cents.

Dave's musings about setting up and adjusting sails on R/C model Boat.

Dry sailing -set up.

Place the model in a stand. Head the model into them wind.

Things that can be moved, and adjusted: Mast step. Mast rake. Boom vangs. Shrouds. stays. Jumper stays. Head stay/jib stay. Sail shape - loose foot. out-hauls.

Attach the sails to the mast.

Set the sail winches in fully trimmed position while allowing sheets to be slack.

Stand the mast with standing rigging attached in the center step position.

Hook the jib swivel into the middle slot of the jib rack. {The jib boom needs to clear the mast.}

Connect the side stays to the chain plates and adjust so the mast is straight and vertical.

Connect the back stay to the back stay fitting.
The jib stay and back stay will need adjusting to set the mast in vertical position.

Move the out-haul of the sails along the boom to give the sails to have some "belly". Pulling the sails out along the boom flattens their shape. The belly (or shape) of the sails will be determined later and the sail shape will be determined by how windy it is.

Where you attach the sheets to the booms will take into account the type and adjustments available for the sail control. The booms should be full out (90 degrees to the center line of the hull) when the SCU is full out and then the booms should be just about over the center line when fully trimmed in. ( I see 10 degrees as suggested angle to center line). The length of jib sheet trimmed and the length of main sheet trimmed is a factor in setting up the sail control so the sails are coordinated properly when sailing. The SCU handles a much longer main sheet than the jib sheet. The use of jib traveler and mainsheet traveler can help position the sails when fully trimmed in. Unless two servos (SCU's) are used a single SCU has the task of coordinating the positioning of the jib and main.

Turn on the R/C and run the SCU.
Test out SCU setting with the sails full out and fully trimmed.

With the mast set up and sails adjusted roughly in position it time to launch and sail.
--
Setting Sail on the water.

Before launching TURN on the radio on the boat. I have seen many models set loose to sail with the on board receiver and sail controls not tuned on and very unhappy skippers watching as their model sails away towards the horizon.

The initial rigging and sail settings are based in getting the model to sail a strait line while close hauled (sails trimmed in) and sailing up-wind.

Properly trimmed the rig will allow the model to sail it self in a straight line with just a minor tendency to "round-up" (i.e. sail itself dead into the wind). If or example you find you are constantly pulling the tiller (i.e. rudder) hard over to pull the model back on course to keep from heading in to the wind your model has weather helm which means your mast and jib must be re-positioned. When tacking if your model stall's into the wind and won't tack? Try different rig setting.

--
Setting Sails
The art of tuning the rig on a sail boat is detailed in books written for racing yachts and boats.

"DINGHY SAILS"
by Jeremy. Howard-Williams

"The Best of Sail Trim:
A Selection of Articles from Sail Magazine"

"Sail Trim: Theory And Practice"
by Peter Hahne

My observations and commentary on tuning are from an amateur and are at best suggestions not professional advice.

Observation Number One!!
Model sails that are single panel loose footed sails rely on the shape of the sail established by the gap between the boom and the foot of the sail. Model sails with "shape" sewn into the sail fabric still are loose footed. Also the lift of the boom also factors in determining the shape and performance of the sails.

Hauling a sail into the center line and at the same time pulling down on the sail can flatten the fabric and kill the sail shape. I like to use travelers to position the sail to the desired point near the center line. Then you can set the point of maximum driving force and not wreck the sail shape.

On a big boat the skipper can changer the suit of sails to match the cut of the sail with the wind conditions. In the case of a model a skipper can change where the out-haul is along the boom, light air adding belly to increase the drive, heavy air pulling the sail out further changing the sail's airfoil.

The jib and mainsail work as a system. A skipper has all manner of combinations that may be set relating the two sails. If the models did not have jib clubs they could overlap the mainsail. So model sailors have to adjust the "slot" between the jib and the main to get the maximum driving combined air foil.

In heavy air you may want to close the slot and ease the main so that the jib slightly back-winds the main to help the model sail flatter (less heeling).

Don't forget on a model it is easy to rake the mast fore and aft to trim the sailing characteristics to match wind conditions.
--
A digital camera can be a terrific diagnostic tool for seeing what is happening on your model. You can look at pictures and spot misadjustments. Bends in mast, wrinkles in sails etc. Does you model's mast rake forward down wind? Is the back stay bending the top of the mast. How are the jumper/jenny stays adjusted do they balance the tensions between the jib and the back stay?
--
The late Manny Costa of RI always stressed, change one thing at a time to see what changes. He also stressed sailing a pair of models. One model being tuned and sailing against the second to see if the single adjustment improved performance.

Round-Robin racing in pairs is an excellent way to evaluate how your model performs.

Fiberglassing materials -- vacuum baging etc

Breather fabric is a lightweight, polyester blanket that provides excellent air passage within the vacuum envelope while it absorbs excess epoxy.
60" wide x 2.7 yd, 60" wide x 10 yd. 60" wide x 200 yd rolls:

Release Fabric is a tough, finely woven nylon fabric treated with a release agent. It is used to separate the absorber, breather and vacuum bag from the laminate in vacuum bagging operations. Excess epoxy bleeds through and is peeled from the cured laminate along with the release fabric. Peels easily and leaves a smooth textured surface, ready for bonding or finishing. 60" wide x 2 yd,. 60" wide x 10 yd rolls

Vacuum Bag Film is a Clear, heat-stabilized, modified nylon resin film, tough, stretchable film for high vacuum pressures. 60" wide x 2 yd, 60" wide x 10 yd,60" wide x 20 yd. 60" wide x 333 yd rolls:

Vacuum Bag Sealant; a mastic tape sealant for airtight seals between vacuum bags and molds. Easy to work with around difficult angles, patching small leaks in the system. 1/2" wide x 25' rolls:

Techniques Book on Vacuum Bagging, West System publishes this definitive guide to the principles and application of vacuum bagging techniques for laminating composite materials
with epoxy.

Fiberglass Mat is a Chopped Strand Fiberglass Mat, Offers great conformability with low cost.

Veil Mat 0.09 oz/sq ft

Fiberglass Mat, 3/4 oz/sq ft, 1.5 oz/sq ft, 2.0 oz/sq ft

Fiberglass Cloth 4-, 6- and 10-oz per square yard.

Dynel Fabric is a popular laminate fabric with great abrasion resistance used for museum-quality restoration work on wooden boats. It's strong and supple like a true woven fabric, with no fibers to irritate your skin.
Size Weight, 5 oz

Carbon Fiber lightweight, strong composite can strengthen any project while adding minimal weight.
Plain Weave 5.8 oz
Twill Weave 5.8 oz
Unidirectional 9 oz

Carbon Fiber Tape a unidirectional reinforcing tapes are used
to improve tensile strength and stiffness in one direction with minimal weight.

--

You can learn a lot about boat building by reading catalogs for example: www.jamestowndistributors.com/
Many of the same materials are also used in model boat building.

The Jamestown site has several links to model builders, AMYA and other organizations

Woode boat Construction -- glues and adhesives

John F. Howard (Star-45 discussion forum, July 31, 2006)

"Gorilla Glue does foam a bit, but nothing like foam-in-a-can and has minimum stink. Forget trying to smooth things out, the foam is very, very sticky and keeps growing until it sets up (about an hour) at which point it will still be a little soft (keep clamped for 3-4 hours). Any squeeze/foam out once hard, can be cut, chiseled or sanded smooth. Run a strip of tape along the edge of the glue line and most of the foam out will end up on the tape. The best joints are tight ones that use a minimum of glue. For narrow or thin pieces (planking), squeeze out a little puddle (just enough to use in 15-20 minutes) and use a Popsicle stick to spread along the edges. Wear gloves, the stuff stains and is sticky. GG is great for laminating larger areas (spread with an old credit card or playing card)."

"If you use epoxy resin such as West Systems (best, you can adjust the cure rate with the different hardeners) or one of the 30-minute or longer (5-15 minute never gets hard and remains rubbery) such as sold by Great Planes or Tower, stink will not be a problem. The polyester resin does STINK in a big way, it what you can smell in a new fiberglass hull.
CA glues are ok for "tacking" stuff in place until the epoxy sets up, but watch the fumes. CA will fail if used in a wet location for long and also cause a problem with the wood accepting stain. Work with plenty of ventilation and or respirator and wear gloves with any of the above glues and resins, staining of the skin and sensitivity, either skin and or breathing can occur."

"These are base on my experience with the glues mentioned (full size boats, cabinet work and models). Yellow glue such as Titebond or Elmers Carpenter Wood Glue (not waterproof) works fine when encapsulated with epoxy (cedar strip canoe builders use it all the time)."

{ http://groups.yahoo.com/group/Star45/ }

Phil Geren adds a warning note about Glue Fumes:
I have a serious allergic reaction to CA fumes - causes fluid to build up in the lungs, like pneumonia. I still use it, but with a fan blowing air between me and the work. Trying to avoid it.

Phil Geren on Gorilla Glue:2006 August 1
Is it rock hard or rubbery when dry?
I bought some, but have the same reservations as Dave M about foaming, trimming, and sanding. If it doesn't sand well, the finished product won't be as good as what I am aiming for.

Fiberglass Cloth, Matt -- polyester resins

This is a guide to assist the model builder in building model sailing boats from kits with fiberglass hulls and associated components.

"FIBERGLASS"

Fiberglass is the common name for glass reinforced plastics, GRP. The strands are produced in a non-woven cloth called matt and in a woven cloth called fiberglass cloth, boat cloth, tooling cloth and woven roving. After the cloth has been saturated with resin and the resin cured (hardened) we have fiberglass. Fiberglass matt and cloth are sold by the yard in small lots by retailers and by the pound by wholesale suppliers. Matt and cloth are designated in thickness by referring to their weights. Matt is weighed by the square foot with 3/4 to 3 oz. matt being most common. Cloth is also weighed but unlike matt it is weighed by the yard. Thus a 9 oz, cloth has the same glass content as 1 oz, matt. Matt and cloth have different handling characteristics and different conformability as well as different impact and strength factors. Working with matt using brush-on resin requires skill and experience to avoid developing one big mess of glass fibers and resin. You will find with a little practice that matt conforms well when worked with a resin-covered surface with a constantly wet brush. A matt called surfacing matt can be used to work the regular matt in place and squeeze out air bubbles and excess resin. This matt is hard to obtain other than from wholesalers. A layer of cloth works well for surfacing if you can stand the added weight. Fiberglass cloth put up in tape form is widely available. It is a convenient way of getting high quality cloth in small quantities. It is important for the glass resin combination to have as high a glass content as possible for strength. Fiberglass cloths used in boat building must have a special treatment called Chroming to make the glass compatible with the resin. Do not use industrial or auto grade fiberglass cloth unless it is treated.
Fiberglass (GRP) laminates will absorb water through the capillary action of the glass fibers. The problem of water absorption and surface abrasion is overcome in the molding stage by adding a specially formulated resin known as gelcoat. Although gel-coat is available clear, it is usually pigmented to give the surface resin a molded-in color. Polyesters and lay up resins can be pigmented giving the part a solid color throughout. This is an inexpensive way of molding color in but it presents two problems - hidden air bubbles within the laminate and exposing glass strands.

Working with Fiberglass "SAFETY" is Important !!

Always work in a well ventilated area. Resins, hardeners, and solvents are flammable and toxic. MEK60 is impact sensitive. Some people are ' especially sensitive to any and all components. Avoid excessive skin contact. Avoid inhaling concentrated fumes. Wash well and keep skin clean from these chemicals. chemicals follow manufacturers instructions. DO NOT SMOKE or have open flame around when working with fiberglass chemicals. Select an appropriate work area. Protect furniture, floors and other surfaces from spills and spatters {.o prevent permanent damage from these substances. Remember that the fibers of the fiberglass are irritants and commonly cause skin itching and irritation. When sanding, use a barrier cream or gloves, protective clothing and sanding mask and clothing and careful clean up methods as you work.

Fiberglass is just that, GLASS, and it will cut if you are not careful. When you sand, cut or trim anything made from fiberglass keep in mind that it can be as sharp as anything known to man.

Fiberglassing information and comments

Polyester resins are formulated in many make ups. To change the liquid resin to a solid you must add a hardener to catalyze the mixture. Whenever resin is referred to in this manual it is intended that it be properly catalyzed before use. The resin you choose for your model should be pre-accelerated. This resin will commonly have a purplish hue in the liquid stage and may change color to indicate states of cure. Resins should be at room temperature (60°-90°F. ) for curing. Among the polyester resins `available are the air, inhibited types. Lay up, spray, and gel-coat resins are formulated so their surfaces will not cure readily while exposed to air. This is advantageous if several layers of glass are to be laminated over a period of time. However, it may present a problem to the unsuspecting buildr who finds the surface of his resin "forever tacky". Sometimes, applying a layer of hard .bowling, alley wax will solve this problem. Gel- coat resins therefore, are' not used as a finish coating on completed boats because they are air-inhibited.

Finishing resin or hand-lay-up resin is commonly a waxed resin. When special waxes are formulated in the resin they will move to the surface as the resin cures. This is an advantage if this is the outer surface. If you want to bond to: this, surface you must first sand it thoroughly and then '" prepare, the surface with acetone or polyester solvent.

Polyester resins may be thinned with acetone and styrene. The common polyester hardener is methyl ethyl kettle peroxide (MEK60). -Resin and hardener 'must' be handled most carefully and in strict accordance with the manufacturers -instructions. The amount of hardener or activator in conjunction `with the room or ambient temperature determines the jel time and the cure' rate' of the resin. The jel time is the period that the resin remains liquid until it turns to a jelly just before curing hard. Resin has a "pot life" and is only workable for the time before it jels; this may vary from seconds to several minutes. CAUTION-DO NOT use too much hardener. Styrene will thin the resin' and become chemically part of the cured resin. Acetone will thin the resin but will evaporate during cure. Acetone will change the characteristics of the cured resin and may result in brittleness and other unwanted characteristics.

Polyesters may be filled with a 'number of components from sawdust to pecan shells. Most common fillers are Cabosil and micro-balloons and macro-balloons. This filling may make the resin thixotropic and filled resin may vary from a slurry to a heavy paste. Macro-balloons and micro-balloons are used to make a foam-like putty that will work as a flotation foam.

Polyester will bond nicely to polyester. We stress that surfaces must always. be cleaned and prepared for bonding. The bond between two fiberglass parts, such as keel and shell or hull and deck, will be enhanced if the interface between bonded surfaces is filled with a layer of saturated matt, cloth, or filled resin. Polyester resin is frequently used to bond to wood as a glue. However among wood glues, polyester rates poor. The initial bond to wood may look all right but it has a history of delaminating. We will not rule out its use for model building. However, there are better wood glues and the best of the waterproof glues are better, many epoxies.

Fiberglass is not at its best under tension. Spread or distribute any tension . load over a wide area. The same goes for compression loads that should be spread out also. This fiberglass found in models will tear if pulled on so always spread the load - more on this later.

You must remove all waxes in order to bond to fiberglass and you can reverse this and coat surfaces with hard floor waxes during building to protect surfaces from accidental spills. Also remember to use only resin-resistant tape such as Scotch brand Cellophane tape which is inert to resins; regular masking tape may be used if not in contact with resin or solvents.

Fiberglass has the outstanding feature that when molded in curves it has very high strength imparted to the part because of the curves. On smaller models the curves of the hull provide sufficient strength for the model. On larger models you will need stiffeners. These may be ribs or bulkheads which add support to the hull. These can be of the aircraft framework type. Another stiffening method is to make a sandwich. Here the strength of the GRP is achieved by laminating a light weight core between two layers of fiberglass.

From: "Mitch Martin" 2006 August 1

Working with WEST is similar to polyester resin, but it is stronger, doesn't smell bad, and hardeners can be selected for your application. For example if I was mixing the epoxy for glassing a hull that would eventially be painted I would select the extra-slow hardener 209 which has a pot life of 45 minutes. That's much longer than a polyester resin pot life. The down side is the cost, it's pretty pricy stuff. Another trick is to mix in the graphite powder and it gives the finish a carbon fiber look.

from John 2006 August 1

The pot life with the 105/209 is 40 min or so. I have used that
combination when doing vac bagging and it allowed plenty of time to wet
out the fabric on a 60" boat, then apply mastic, then the bagging
materials, then pull the air out. I have also done 72" long 10R's and had
no issues with the pot life. Now I am usually about 70 deg, so that slows
it down some too.

Now the 105/205 can be more in the 10 to 20 min range depending on temp.
Also how deep the container is that you mix the epoxy will influence the
cure time. Deeper is faster.

Billie Geisler's comments regarding Epoxy:

I use strips of cardboard scissored from breakfast ceral boxes for mixing and applying the epoxy. I use aluminum beer cans for containers. I cut the bottoms off about an inch up the can with a curved exacto knife. I find that I can get a pretty good mix of resin to hardener by cutting the mixer cardboard the same size, then use them to measure the epoxy and hardener.

I dip the cardboard mixer stick into the resin and scrape off all that will remain on the stick, after I wind up the strings, into the beercan. Then I use another fresh cardboard mixer stick, and dip it into the hardener to the same depth as I dipped the first stick into the resin. I let it drip once before I scrape it into the beer can. The difference in viscosity seems to get the ratio about right, even though it seems that no way is the little bit of hardener that stays on the dipper is going to be enough to work. The cardboard mixer sticks are inserted vertically into the resin and hardener, and scraped on the edge of the beer can.

You can pretty accurately go from a hot mix to a slow mix by simply varying the depth of the mixer stick in the hardener. It works on very small amounts, and about two dips from a half inch wide cardboard mixer stick will be enough for a plank on each side.

I use small jars to contain the epoxy components that I am working with, and label both the jar and the matching lid as resin or hardener. That way, if I happen to dip the used hardener dipper into the resin, or mix up the lids, I don't loose my whole supply. I like horshradish jars from Kraft.

Experiment with your epoxy before smearing it on your hull, as my epoxy is about 20 years old and the ratio of hardener to resin may work differently with yours. Just vary the depth of the hardener dip relative to the depth of the resin dip, until it works for you. It doesn't take long to learn to mix very small amounts with reliable cure results.

Billie Geisler's comments regarding Epoxy:

I use strips of cardboard scissored from breakfast ceral boxes for mixing and applying the epoxy. I use aluminum beer cans for containers. I cut the bottoms off about an inch up the can with a curved exacto knife. I find that I can get a pretty good mix of resin to hardener by cutting the mixer cardboard the same size, then use them to measure the epoxy and hardener.

I dip the cardboard mixer stick into the resin and scrape off all that will remain on the stick, after I wind up the strings, into the beercan. Then I use another fresh cardboard mixer stick, and dip it into the hardener to the same depth as I dipped the first stick into the resin. I let it drip once before I scrape it into the beer can. The difference in viscosity seems to get the ratio about right, even though it seems that no way is the little bit of hardener that stays on the dipper is going to be enough to work. The cardboard mixer sticks are inserted vertically into the resin and hardener, and scraped on the edge of the beer can.

You can pretty accurately go from a hot mix to a slow mix by simply varying the depth of the mixer stick in the hardener. It works on very small amounts, and about two dips from a half inch wide cardboard mixer stick will be enough for a plank on each side.

I use small jars to contain the epoxy components that I am working with, and label both the jar and the matching lid as resin or hardener. That way, if I happen to dip the used hardener dipper into the resin, or mix up the lids, I don't loose my whole supply. I like horshradish jars from Kraft.

Experiment with your epoxy before smearing it on your hull, as my epoxy is about 20 years old and the ratio of hardener to resin may work differently with yours. Just vary the depth of the hardener dip relative to the depth of the resin dip, until it works for you. It doesn't take long to learn to mix very small amounts with reliable cure results.

Star45 hull being fiberglassed

Covering Star45 model hull with fiberglass and epoxy resin

From: "John Fisher" racer577 at citystar.com
I have used the 3.2 oz satin weave on 7 boats now. The first was a single layer and now that hull is 4 or 5 years olds it is showing wear and tear. I went to using 2 layers to help with durability and to have more material for sanding. Another thing I like about the cloth is that is drapes very nicely and easily will cover the hull with one pc. On my 10R's I have used 2 yards folded in half to do the hull. On the star I was concerned that it would be too wide for a single yard. I ended up with more than enough material so I cut it on the diagonal.

The glassing starts by laying the glass over the hull. Then I smooth it out so there are no wrinkles. This may take a couple of min. Then I repeat with the next layer. Once the glass is smooth, time for epoxy. I used the 209/105 west systems combination. I used about 10 pumps of material.

I start applying resin to the middle of the bottom with a cheap paint brush. Then I work my way out to the edges of the bottom. Next I do the sides. You need to use lots of resin and dont pull too much or you will pucker the cloth. Once everything is wetted out I go back with a squigee and remove the excess resin. Dont get to carried away or the cloth will go dry again. If in doubt of how this should look practice on a spare block of wood first to get a feel for how the cloth looks as you take out resin.

I did the glassing at about 8 pm and with the 105/209 the resin is still green at 7 am the next morning. When green the glass can be trimmed with a #11 blade in a hobby knife. Then wait another day or two until sanding for full cure. I dont like to do much sanding, instead I try and do most of my fairing by using a thick primer and sanding most of it off between coats. For a clear boat I use polyurethane for a top coat.

Stand for tuning finished model

John Fisher sent these in. It might spark some thought for other people as well. He does not claim to have come up with this design, You can use any materials that you have handy, He has a mill and a welder, so his ended up in aluminum. these stands have been built from PVC and Copper pipe as well.

The stand has a vertical tube that is the pivot for direction. This way the boat can feather into the wind. If the ground is soft enough where you sail it can be pushed into the ground. Works fine in so-cal but not very well in colorado. Next there is a H shaped part that holds the boat. His are machined and welded aluminum, but he has seen this part done with copper water pipe or PVC pipe. He added the foam for insulating water pipes to prevent the boat from being scratched. The H should be able to rotate. This allows the boat to heel in the stand when force is applied to the sails. Connect the two and you have your stand. On his stand the connector is a pcs of 1/2" diameter SS tubing bent 90 deg. It provides both motions needed.



The boat shown is a hard chine 10R Class called the Diamond.


John Fisher has cutting files available for hard chine model 10R Class as well.
They go fast :-). John's 10R Class carries 1500 sq in of sail, is 65"
long and only 9" wide.

Star 45 Setting Sail -- on-line "How To Sail" resources

From: "Don Keeney" <1keyknee@281.com>
Date: Sun, 19 Nov 2006 15:39:26 -0600
Subject: [Star45] Sail Trim

A great place to learn about sail trim and sailing in general.
http://www.sailingusa.info/sail_trim.htm

Don Keeney
Star 45 Class Secretary
--
Outstanding recommendation. Wonderful site. full of photographs and all sorts of instructional materials. Pictures of tells and how to read them:)

Another must place to visit (you can try out your sailing skills):
National Geographics Interactive Sailing:

Master rudder and sail to get your boat going as fast as possible no matter what direction you're sailing in-or which way the wind's blowing.

Controls available:

Sail Adjuster: Use the left sliding controller to rotate the sail in relation to shifting wind (shown as arrows). When you cross the path of the wind, your sail will swing to the opposite side.

Rudder Adjuster: Using the right sliding controller, steer to port (left) or starboard (right).


Uncle Dave

modern sail materials, North Cloth - Industrial Fibers

by Peter Mahr and Brian Doyle
http://na.northsails.com/North_Cloth/industrial_fibers.html

Almost every piece of modern sailcloth begins life as an industrial fiber. While the brand names of many of these fibers are well known to sailors, their basic properties are less well understood. The characteristics of these fibers are an important factor to consider when choosing sails for your boat. Over the past few years there have been some significant developments in high performance fibers that have applications in sailcloth. The result is a greater variety of options for performance sailcloth makers and their customers, allowing them to select the blend of performance, durability and cost that best suits their needs.

Polyester
Polyester is today's "classic" sailcloth fiber. It is often called by the Dupont trade name DACRON® although there are other suppliers of polyester yarn used in sailcloth. Polyester is widely used for its combination of reasonably low stretch, good strength, low cost and durability. Because it can be heated and shrunk during weaving to form a tight, stable woven cloth, polyester woven sailcloth remains a good choice for cruising sails and certain racing sails. Polyester is available in many types. Dupont’s Type 52 is a "high-tenacity" premium fiber offering a balance of higher strength, lower stretch and maximum shrinkage. Other premium polyesters, with comparably excellent properties at more attractive prices, are now available from Asian and European suppliers. Their use in sailcloth has increased over the last few years at the expense of Dacron.

Nylon
Nylon is used for most downwind sails because it is strong and light. Nylon is relatively stretchy, allowing it to absorb shock loads and making it easier to fly and more stable in wavy seas than a polyester material would be. Dying this fiber is easier than any other and it is often available in a variety of colors.

Aramids
A popular class of high performance fiber in laminated sailcloth is the Aramids. The most well known aramids are Kevlar™ (a Dupont trademark) and Twaron™ (made by Teijin/Twaron of Japan). Sails made with aramid fiber are lighter than woven Dacron or Polyester laminates, and have greater effective wind ranges. The tradeoff is higher cost and shorter sail life. The stiffer Aramid fiber is more susceptible to sunlight (UV) damage and breakdown due to folding and flogging.

Aramids are produced in a number of different styles, with different balances of stretch, flex strength, weight and cost. High modulus (low stretch) types such as Kevlar 49 and Twaron 2200 are the most appropriate choice for racing sails. A variation of Kevlar called “Edge” was promoted a couple of years ago because it had slightly higher initial modulus. North’s testing revealed that this effect disappeared almost immediately with use. This type has since been discontinued.

Another aramid fiber is Technora, which is similar to medium modulus Kevlar in chemistry and performance. Initially it has a bit higher strength but loses strength more rapidly in UV making it similar in durability in most applications. It is commonly seen with a black coating, which is intended to provide some UV screening.

Vectran
Vectran is a LCP (liquid crystal polymer) fiber sold by Hoechst. Vectran’s stretch resistance is nearly as high as a standard modulus aramid, and it is somewhat stronger when new. It differs from aramids in its chemistry and has somewhat better flex resistance as long as it is shielded well from UV. Under UV exposure, it degrades more rapidly than aramids and far faster than Spectra/Dyneema.

Carbon Fiber
First used successfully in the 1992 America's Cup, carbon fiber laminates provide exceptionally low stretch and light weight at the expense of higher cost and somewhat shorter life span compared to an aramid sail. Careful R+D and on the water testing is critical with this fiber. Carbon is available in a wide variety of types, only a few of which can tolerate the flexing seen in normal sail use. Laminating techniques are also very critical to get the available high performance as well as to achieve the best possible durability. Experience over that last few years on top boats with 3DL carbon and carbon/aramid sails has been very positive and the fiber is seeing increasing use by more types of boats.

Spectra/Dyneema*
Spectra, and its European counterpart Dyneema, offer even lower stretch, higher strength, better UV resistance and much less strength loss in flex than Kevlar. However, Spectra/Dyneema sails stretch (creep) under long-term load, which makes them unacceptable for racing sails. After considerable development, this fiber is now used with excellent results in sails for large performance cruising boats.

* Note: We use the somewhat awkward ‘Spectra/Dyneema’ reference since we employ the two fibers almost interchangeably and sometimes in the same piece of cloth

PBO
At the top of the theoretical performance list is PBO, a fiber made by Japanese company Toyobo. This fiber has been used for a number of years in both 3DL and paneled sails. It has proven to be somewhat better than an aramid sail in performance when new but degrades rapidly under the combination of UV and flex. Because it is a very expensive fiber, its use in sails has all but disappeared in favor of the even higher performance and more durable carbon option.

PEN
PEN is a fiber with stretch between polyester and aramid and with slightly higher strength than polyester but far less than aramid. That combination and a cost approaching aramid have meant that this fiber has limited application in sails. It has been ruled to be polyester and as such can be used in one-design classes that limit their sails to polyester.

Summary
New fibers continue to come out of the labs. Some will become standards while others will disappear. Despite the promise of these exciting new fibers, design still plays a vital part in their successful application in your sails. Simply inserting a spicy new fiber in a poorly engineered fabric or sail design is a formula for failure. Similarly, enough of the fiber must be used to handle the sailing loads and the abuse it will take in tacking, flogging and handling. Low stretch has always been desirable in selecting fibers for sailcloth but this is only one element in a sail's performance. It is ultimately the combination of fiber, fabric and sail design that makes for a winning sail.

Fortunately for North our 3DL molded sailmaking process allows us to produce a test sail from a new fiber within a few days of its arrival at our factory in Nevada. This has allowed us to quickly evaluate new offerings and to remain the industry’s technological leader.

Pictures of International Star Class Yachts under sail

Photographs by Fried Elliott
PO Box 940010
Plano, TX 75094

email: fried @ friedbits.com

Classic International Star Boat