Foam sandwich plans

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jacquesmm
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Foam sandwich plans

Post by jacquesmm »

Many ask for a foam sandwich version of my plans. It is correct that many of my designs can be built in foam sandwich and I know the material well: I designed for foam sandwich well before plywood-epoxy.

A good foam sandwich version of my designs will have the same hull shape and be close in weight but many parts must be recalculated.
The foam sandwich boat will use more layers of glass, use a different type of resin (SilverTip), specific types of foam. The hulls will be thicker, the framing spaced more widely and the gull assembly different.
I want to redesign the boats for foam sandwich and supply good building instructions.

Except for a few boats (PH15, LB26 and maybe some others that I forgot), there are no official plans for foam sandwich boats. For some designs, I have given specs to a few builders but I prefer to offer complete plans for foam sandwich versions with a nice shop manual. You can't simply switch the core type, there is much more to it if you want it done right.
I am almost ready with a very detailed foam sandwich shop manual for small boats but I have to work more on the layout, change some pictures then proofreading. It is already between 35 and 100 pages depending on the size of the drawings.
There will be more than one manual.
The first one will cover small boats built without a jig.
The second one will be for small to medium size boats built on a jig. Later, the third one will be for large units.
I started writing them as one manual 2 years ago and it was confusing, I had to separate them in 3 books with many common parts.
The plans will follow. There are differences: the framing is different, there are many high-density inserts and because of the thickness of the core many dimensions change.
In the mean time, this the traditional method to build in foam sandwich:
http://bateau2.com/howto/foam1.php

The manuals that I am working on will show a faster, easier method close to our plywood-epoxy boats.
Jacques Mertens - Designer
http://boatbuildercentral.com

fallguy1000
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Re: Foam sandwich plans

Post by fallguy1000 »

These will be much appreciated.

Make sure to read my hot glue thread.

Building with foam is interesting. I am still nervous about whether my vac bag work (hulls) is any good. They are sort of right on the edge of minimal resin to glass ratio. Ideal is sort of scary.

I still wish I had learned panel infusion; better quality control, less stress, less waste. I suppose you will need to
mostly avoid great details on the how to laminate?
My boat build is here -------->

viewtopic.php?f=12&t=62495

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antoniekruger
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Re: Foam sandwich plans

Post by antoniekruger »

jacquesmm wrote: Thu Nov 01, 2018 11:52 am Many ask for a foam sandwich version of my plans. It is correct that many of my designs can be built in foam sandwich and I know the material well: I designed for foam sandwich well before plywood-epoxy.

A good foam sandwich version of my designs will have the same hull shape and be close in weight but many parts must be recalculated.
The foam sandwich boat will use more layers of glass, use a different type of resin (SilverTip), specific types of foam. The hulls will be thicker, the framing spaced more widely and the gull assembly different.
I want to redesign the boats for foam sandwich and supply good building instructions.

Except for a few boats (PH15, LB26 and maybe some others that I forgot), there are no official plans for foam sandwich boats. For some designs, I have given specs to a few builders but I prefer to offer complete plans for foam sandwich versions with a nice shop manual. You can't simply switch the core type, there is much more to it if you want it done right.
I am almost ready with a very detailed foam sandwich shop manual for small boats but I have to work more on the layout, change some pictures then proofreading. It is already between 35 and 100 pages depending on the size of the drawings.
There will be more than one manual.
The first one will cover small boats built without a jig.
The second one will be for small to medium size boats built on a jig. Later, the third one will be for large units.
I started writing them as one manual 2 years ago and it was confusing, I had to separate them in 3 books with many common parts.
The plans will follow. There are differences: the framing is different, there are many high-density inserts and because of the thickness of the core many dimensions change.
In the mean time, this the traditional method to build in foam sandwich:
http://bateau2.com/howto/foam1.php

The manuals that I am working on will show a faster, easier method close to our plywood-epoxy boats.
Hi Jacques,
Thanks for the link, I had a read and did some other research on the foam core builds. I have some questions - I'll be using my CS23 build for the discussion:
1. I understand the foam planking over the battens - lets call it horizontal planking. I found quite a few examples where vertical planking was used. The hull shape was laid out from the inside and the foam was planked inside the shape and then laminated, doing the hull in 2 halves and then joining them. What is your opinion on this?
2. Shooting from the hip, how much more glass will be used in a foam project - factor of 2 or 1.5?
3. How much more expensive will a foam project be, again a factor - 2 or 3 times?
4. What are the benefits of doing a foam core over the ply sandwich? (weight, no wood...)

Thanks,
CC14 splashed
CS23 almost there

fallguy1000
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Re: Foam sandwich plans

Post by fallguy1000 »

antoniekruger wrote: Sun Nov 04, 2018 5:27 am
jacquesmm wrote: Thu Nov 01, 2018 11:52 am Many ask for a foam sandwich version of my plans. It is correct that many of my designs can be built in foam sandwich and I know the material well: I designed for foam sandwich well before plywood-epoxy.

A good foam sandwich version of my designs will have the same hull shape and be close in weight but many parts must be recalculated.
The foam sandwich boat will use more layers of glass, use a different type of resin (SilverTip), specific types of foam. The hulls will be thicker, the framing spaced more widely and the gull assembly different.
I want to redesign the boats for foam sandwich and supply good building instructions.

Except for a few boats (PH15, LB26 and maybe some others that I forgot), there are no official plans for foam sandwich boats. For some designs, I have given specs to a few builders but I prefer to offer complete plans for foam sandwich versions with a nice shop manual. You can't simply switch the core type, there is much more to it if you want it done right.
I am almost ready with a very detailed foam sandwich shop manual for small boats but I have to work more on the layout, change some pictures then proofreading. It is already between 35 and 100 pages depending on the size of the drawings.
There will be more than one manual.
The first one will cover small boats built without a jig.
The second one will be for small to medium size boats built on a jig. Later, the third one will be for large units.
I started writing them as one manual 2 years ago and it was confusing, I had to separate them in 3 books with many common parts.
The plans will follow. There are differences: the framing is different, there are many high-density inserts and because of the thickness of the core many dimensions change.
In the mean time, this the traditional method to build in foam sandwich:
http://bateau2.com/howto/foam1.php

The manuals that I am working on will show a faster, easier method close to our plywood-epoxy boats.
Hi Jacques,
Thanks for the link, I had a read and did some other research on the foam core builds. I have some questions - I'll be using my CS23 build for the discussion:
1. I understand the foam planking over the battens - lets call it horizontal planking. I found quite a few examples where vertical planking was used. The hull shape was laid out from the inside and the foam was planked inside the shape and then laminated, doing the hull in 2 halves and then joining them. What is your opinion on this?
2. Shooting from the hip, how much more glass will be used in a foam project - factor of 2 or 1.5?
3. How much more expensive will a foam project be, again a factor - 2 or 3 times?
4. What are the benefits of doing a foam core over the ply sandwich? (weight, no wood...)

Thanks,
1-vertical planking is done on round bilge/hull boats where the foam is heat formed to a round shape. It would be waste of efforts to vertical plank a boat with flatter sides.
2-glass and epoxy are more in a foam build, it is hard to quantify -- foam boats cost more than plywood; the thing most foam boat builders want a boat with a core that won't rot and a lighter vessel with more loading capacity-there is a delam threat in a foam boat
3-hard to quantify - you have to do it for each plan and build method-vacuum bagging produces better results, but costs more
4-core won't absorb water
My boat build is here -------->

viewtopic.php?f=12&t=62495

jacquesmm
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Re: Foam sandwich plans

Post by jacquesmm »

antoniekruger wrote: Sun Nov 04, 2018 5:27 am Thanks for the link, I had a read and did some other research on the foam core builds. I have some questions - I'll be using my CS23 build for the discussion:
1. I understand the foam planking over the battens - lets call it horizontal planking. I found quite a few examples where vertical planking was used. The hull shape was laid out from the inside and the foam was planked inside the shape and then laminated, doing the hull in 2 halves and then joining them. What is your opinion on this?
There are many ways to plank a hull with foam. I go in details about that in the shop manuals I am working on. For larger hulls built on a slat mold, full panels either thermoformed or scored work well. Diagonal planks work well too for round bilge boats. There is another method developed by Canadian Andre Bilodeau using strip planks. For my plans up to 25' hulls, I will propose another method similar to plywood-epoxy panels. It does not require a slat mold and uses large panels with a thin skin on one side. I don't want to elaborate now, I prefer to keep working on the manuals.

2. Shooting from the hip, how much more glass will be used in a foam project - factor of 2 or 1.5?
3. How much more expensive will a foam project be, again a factor - 2 or 3 times?
Rough estimate: 2.5 to 3 times more depending on the boat.


4. What are the benefits of doing a foam core over the ply sandwich? (weight, no wood...)
Too wide a question, sorry.
Jacques Mertens - Designer
http://boatbuildercentral.com

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antoniekruger
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Re: Foam sandwich plans

Post by antoniekruger »

OK, thanks fellas.

Will these manuals you are compiling be in the public domain or only available to people buying foam designs?
I think my next build will be a foam core build - In my nick of the woods it will make it more sell-able than a ply core.
CC14 splashed
CS23 almost there

jacquesmm
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Re: Foam sandwich plans

Post by jacquesmm »

I plan to include the shop manuals with the plans for foam core but also sell them separately, for a nominal fee (like $ 10.00) on Amazon.com and at bateau.com.
Jacques Mertens - Designer
http://boatbuildercentral.com

Fuzz
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Re: Foam sandwich plans

Post by Fuzz »

jacquesmm wrote: Sun Nov 04, 2018 1:43 pm I plan to include the shop manuals with the plans for foam core but also sell them separately, for a nominal fee (like $ 10.00) on Amazon.com and at bateau.com.
I am betting they will sell like hot cakes :wink: If there is going to be one for small, medium and large boats you can go ahead and sign me up for each :D

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Re: Foam sandwich plans

Post by antoniekruger »

Hi J, can we pre-order......no pressure :D
CC14 splashed
CS23 almost there

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Re: Foam sandwich plans

Post by jacquesmm »

antoniekruger wrote: Mon Nov 05, 2018 9:15 am Hi J, can we pre-order......no pressure :D
That would be pressure. :D
Let me do it right. I may release a 1st draft version earlier for those who want to start on their build.
Jacques Mertens - Designer
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