Anatomy of a boat by G.L. - FINISHED - scale 1/10 - POF - SMALL

[FriedClams]

Very nice detail with that metal keel G.L.  The bar tin that you used - was that a 50/50 tin/lead or a lead free bar at 97% tin, with antimony/copper/silver?  The reason I ask is because it seems to have flowed into your mold quite nicely.  I would have expected lots of air bubbles and voids.  Also, I noticed the wood plug you used to form the plaster mold is shiny.  Did you slather the wood with petroleum jelly or something else as a release agent?  Enjoying your log.  Thanks

 

Gary

[KeithAug]

GL - Your casting of the keel was very interesting. Like Gary I would welcome a bit more detail, particularly around making the mould.

[G.L.]

On 12/11/2019 at 10:39 AM, aviaamator said:

We look forward to continuing!

 

On 12/11/2019 at 1:15 PM, Backer said:

Great work 

And a very wise decision 

 Thank you very much Aviaamator and Patrick

[G.L.]

23 hours ago, FriedClams said:

Very nice detail with that metal keel G.L.  The bar tin that you used - was that a 50/50 tin/lead or a lead free bar at 97% tin, with antimony/copper/silver?  The reason I ask is because it seems to have flowed into your mold quite nicely.  I would have expected lots of air bubbles and voids.  Also, I noticed the wood plug you used to form the plaster mold is shiny.  Did you slather the wood with petroleum jelly or something else as a release agent?  Enjoying your log.  Thanks

 

Gary

 

19 hours ago, KeithAug said:

GL - Your casting of the keel was very interesting. Like Gary I would welcome a bit more detail, particularly around making the mould.

 Gary and Keith,

I have no idea what it's the composition of the tin bars, I just bought them by the ironmonger and dit not ask about.

The wooden plug and the baseplate to make the mold are shiny because I varnished them with high gloss varnish (forgot to report that in my post) to make them less water absorbing so they would loose easier from the plaster. When the plaster was dry the plug was strongly clamped in the plaster (due to its shape), impossible to pull it manually from the mold. I used a car jack. (tried to reconstruct the method to make the picture below.)

The casted piece had to be pulled out using the same method, but that had the appendix of the pour funnel that worked as a liver on the plaster mold which made it crack.

Fortunately the quality of the  casted piece was acceptable and the mold didn't had to be used any more.

Between the making of the plaster mold and the pouring of the tin, I waited one week. Probably it would have been better to wait at least twice that time because during pouring, the melted tin was quite fizzy. I believe that that was caused by the humidity which was still in the plaster although it seemed dry.

[KeithAug]

Thank you G.L.

[michael mott]

Following along GL the casting turned out alright, even if you had some issues with getting it out of the mold.

a very slight taper from the top to the bottom about 2degrees and the and smearing the wood with Vaseline will make the next keel that you cast slide out of the mold much easier.

 

Michael

[FriedClams]

Thanks for the additional information on your casting procedure G.L - I appreciate it.  I can think of several applications where this type of mold casting would be useful.

 

Gary

[G.L.]

On 12/12/2019 at 9:03 PM, michael mott said:

Following along GL the casting turned out alright, even if you had some issues with getting it out of the mold.

a very slight taper from the top to the bottom about 2degrees and the and smearing the wood with Vaseline will make the next keel that you cast slide out of the mold much easier.

 

Michael

Thank you for the advise Michael. I will certainly cast more pieces in the future and take it into account. 

[G.L.]

I glue two planks together to make the transom.

With the help of a paper template, the transom is sawn out.

 

The glued parts are reinforced with bamboo dowels.

 

[G.L.]

2. The frames

The vessel has 22 frames. Frame drawings are not included in the book 'Apprendre le modelisme naval' so I will have to make myself. No worry, I like the drawing board work.
I start by drawing the front and aft side of the frames on the half breadth plan and then measure the measure of each water line on the front of the frame with the divider.

I bring over the measurement to the frame plan and mark it.

I do the same with every buttock line.

At the end, I have a series of pencil marks which show the outline of the frame.

With the help of the French curve rules the marks are connected and form the shape of the front side of the frame.

The whole process is now to be repeated to draw the back side of the frame.

The complete frame. The uninterrupted line is the front side of the frame and the dashed line is the back side of the frame. On this drawing the insides of the frame are also drawn as well as the subdivision in futtocks.

It takes some time, but after a while all 22 frames are drawn. Now we make a jump ahead of some weeks and here they are spread out on my desktop.

 

Thank you for the likes

Thank you to follow

Thank you for your constructive comments.

 

Till next week!

 

[druxey]

Nicely lofted frames, G.L. 

 

A safety note: Never cast molten metal into a plaster mold unless the mold is completely dry!  Moisture can turn instantly to steam, spraying molten metal at you. I recommend drying out the plaster in an oven at very low warming temperature.

[Baker]

G.L.

Hoed af voor uw technisch tekenen (I take my hat off for your drawing skills).

 

Druxey, 

Thanks for the warning

[KeithAug]

On 12/19/2019 at 5:01 PM, G.L. said:

At the end, I have a series of pencil marks which show the outline of the frame.

GL - good to find someone else who has missed the CAD revolution.

[PopDavid]

On 12/19/2019 at 9:09 AM, druxey said:

druxey said:

A safety note: Never cast molten metal into a plaster mold unless the mold is completely dry!  Moisture can turn instantly to steam, spraying molten metal at you. I recommend drying out the plaster in an oven at very low warming temperature.

This is so true.  Dry a plaster mold until you run out of patience, then dry it so more!  Many, many years ago I made a plaster mold in an old coffee can to cast my ducks (spline weights  3-4 pounds  1.3-1.8k) to do some yacht designing.  It was still not completely dry for the first couple of pours.  Exciting!  I use a small cast iron frying pan, BBQ brickets, and a vacuum cleaner (Hoover) hooked up as a blower.  To all who may what to cast their own, there are many educational home foundry and pattern making videos on You Tube.

 

[G.L.]

On 12/19/2019 at 6:09 PM, druxey said:

Nicely lofted frames, G.L. 

 

A safety note: Never cast molten metal into a plaster mold unless the mold is completely dry!  Moisture can turn instantly to steam, spraying molten metal at you. I recommend drying out the plaster in an oven at very low warming temperature.

 

On 12/20/2019 at 10:55 PM, PopDavid said:

This is so true.  Dry a plaster mold until you run out of patience, then dry it so more!  Many, many years ago I made a plaster mold in an old coffee can to cast my ducks (spline weights  3-4 pounds  1.3-1.8k) to do some yacht designing.  It was still not completely dry for the first couple of pours.  Exciting!  I use a small cast iron frying pan, BBQ brickets, and a vacuum cleaner (Hoover) hooked up as a blower.  To all who may what to cast their own, there are many educational home foundry and pattern making videos on You Tube.

 

thank you for your comment on the frames Druxey.

 

Druxey and David,

Yes, I could experience myself how important it is to let a plaster mold dry completely before casting melted metal in it. Despite the mold felt and  looked completely dry, there was some steam development which made the metal fizz, luckily it didn't spatter. Drying the mold out in the oven is indeed a good idea.

[G.L.]

On 12/19/2019 at 7:40 PM, Backer said:

G.L.

Hoed af voor uw technisch tekenen (I take my hat off for your drawing skills).

 

On 12/20/2019 at 9:00 PM, KeithAug said:

GL - good to find someone else who has missed the CAD revolution.

Thanks Patrick

Keith, it is just one of the many revolutions that I missed.

[G.L.]

Before making the frames, I make the building board.
Here I do not follow the handout. Mr Gerd Löhmann is a professional boat carpenter, he builds his model like he would be building the real vessel. I choose to use a more common model building method.
My building board:

Building board after the keel has been laid.

[G.L.]

Starting to make the frames.
I first lay a copy of the frame drawing on an upside down carbon paper and push through the drawing to obtain the frame drawing on the back side of the paper.

 

The I extend the futtock ends with a long pencil line.

The pencil lines help me to place the different parts of the frame. I glue the first layer on the drawing with a paper glue stick.

The frames of the boat are single futtock frames which are only doubled at the joints. I find it easier to saw and sand them as fully doubled frames, so I glue temporarily spruce wood dummy futtocks which will be removed afterwards. I make the frames also some 2.5 cm higher than needed.

First layer is glued. Only the cherry wood parts are glued together with wood glue. I beware to not put glue between the cherry and the spruce parts.

Gluing the second layer. Also here I put only wood glue between the cherry wood parts. Where a spruce (dummy) piece comes on top of a cherry piece I put a piece of paper between it and glue the parts with strongly water diluted wood gluer.

The whole frame is glued.

Now I lay the frame in my 'frame box' that I used already for making the frames of my shrimper and the smack cross section. The inside measurements are exactly those of a A4 paper, sot the frame drawing just fits in it.

The box makes it possible to glue easily another frame drawing on top of the frame, just in the exact position. This drawing will serve to saw out the frame.

On top of the frame goes now a plank (A4 format) and some lead weights and the glue may dry. In the box is space for three frames on top of each other.

After a couple of hours when the glue is dry, the frame can be sawn.

Afterwards the sides (saw cuts) are  sanded with the band- and disk sander. At the same time I sand the slope at the sides of the frame.

 

I tree nail the double parts of the frame.

Before sanding of the frame drawing, I mark the top and the water line on the sides of the frame.

Now the paper can be sanded off.

Foto 108

The spruce dummy futtocks can easily be removed with a small sharp chisel thanks to the paper which is glued between the two layers.

 

When all the paper traces are removed, the frame can be placed on the keel.
The first three are in place:

 

 

Thank you for the likes

Thank you to follow

Thank you for your constructive comments.

 

Happy New Year

 

Till next year!

 

Edited December 26, 2019 by G.L.

[vaddoc]

Wonderful drawings! I like the a4 box trick. In the past I struggled lining up both faces of the frame, this seems to have worked fine

I ll be following from the back rows GL

 

Vaddoc

[KeithAug]

GL - Interesting and educational. Nicely done.

[michael mott]

Very interesting how you set the frames up, it does seem like a lot of work though. your drawings of them are wonderful. I am thinking that one of these days it would be fun to make a small boat and only use hand tools both drawing and the building, and this is what you are doing (mostly). I am enjoying watching the boat take shape. 

 

Michael

[druxey]

The use of sacrificial spruce is an interesting idea. Your positive registration of the drawings and stock in the box is also neat.

Edited December 31, 2019 by druxey

[G.L.]

Thank you very much for your interest, Vaddoc, Keith, Michael and Druxey.

Thanks for the likes!

 

Continuing making and placing frames.

 

Starting the fourth frame from the bow, the frames are half frames.

Also frame 15 to 22 at the aft are half frames.

[G.L.]

It takes a while before all frames are made and placed because in between I have to saw and plane planks to 4 mm thickness which is very time consuming.

 

 

Before placing the after frames I sand the bevel to the transom sides and glue the transom into place.

Finally, all frames into place.

 

 

 

 

Thank you to follow.

Thank you for the likes.

 

Till next week!

 

 

 

Edited January 8, 2020 by G.L.

[FriedClams]

A nice process for producing the frames G.L. and very clearly explained.  With all the frames now placed, the shape of a graceful craft suddenly appears.  Very nice work.

 

Gary 

[G.L.]

Thank you Gary.

 

I am now passing to the next step.

 

3. Keelson and mast step

Marking the recesses for the frames on the keelson.

Sawing out the recesses.

The top of the keel has a curved line so the keelson needs some force to be pushed into position. When gluing, I support is with a prop. The top level of the building board is a handy help to clamp it below.

 

 

The keelson into place.

I tree nail the keelson through the floor timbers into the keel.

 

Before going further I sand the inside of the frames. I use a curved wooden sanding block on which I staple sandpaper of different grits.

Making the mast step. I drill two holes in the block and chiseled the space between them out to one hole. Then I make the two sides sloping and finally I sand the bottom side into the same curve as the topside of the keelson. I see now that I was a bit lazy in making photos of the making process.

Gluing the mast step.

 

 

 

 

Thank you to follow

Thank you for the likes

Thank you for your constructive comments

 

Till next week!

[yvesvidal]

WOW! You made some serious progress.

 

Yves

[vaddoc]

Looking very good GL, lovely hull!

I think we both need a better camera though!😉

[G.L.]

On 1/16/2020 at 8:21 PM, yvesvidal said:

WOW! You made some serious progress.

 

Yves

 

On 1/19/2020 at 8:06 PM, vaddoc said:

Looking very good GL, lovely hull!

I think we both need a better camera though!😉

Thanks Yves and Vaddoc.

And yes I will have to have to take more care in making sharper photos.

[G.L.]

4. Wale, beam clamp and floor heads thick stuff

Gluing the wale into place.

When both wales are into place I place the beam clamps. They have to be glued at the same altitude as the wales, therefore I place a lath from wale to wale as a guide to glue the beam clamps.

 

 

Now I glue the  floor head thick stuff.

The hull is now stiff enough to be taken out the building board ...

 

... and to be sanded at the outside.

 

 

I tree nail the beam clamps and the floor head thick stuff at the inside of the hull before placing the deck beams. The wales at the outside can still wait some time.

I saw the frames equal to the topside of the wales with a metal saw blade.

 

 

 

Thank you to follow

Thank you for the likes

Thank you for your constructive comments

 

Till next week!