Hi-Density Foam for filler blocks?

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I'm wondering if anyone has tried a hard foam instead of wood for filler blocks? Not styrofoam, but polyurethane. It's pretty hard but fairly easy to shape, withstands heat and chemicals (epoxy) cuts with a blade/saw/hot knife as well as having excellent memory. There are 3 densities I am very familiar with

I'm in the preliminary stages of MS Constitution and the filler blocks seem like oak or something (j/k) and it's daunting. I don't think it's balsa.

Also, is it the norm for manufacturers to fold plans 4-5 times? Mine are creased a bit and for the $$$ I was expecting a wee bit more. Maybe not mylar plans (which is what I am thinking to do) but maybe rolled? Or better yet rolled in a cardboard tube...
This is my second build and the first was MS as well. Just wondering if other manufacturers do things differently.

TIA,
Bobby
 
I have used expandable foam in a rattle can with great success, but balsa blocks is easier and a cleaner option.

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Thanks. Yes that stuff can get messy but can also be very handy and sometimes the only solution.
The stuff I plan to use comes in sheets/blocks in many varying dimensions. It's basically the stuff that surfboads are made of.

I'm beginning to think the idea may be blasphemous...
 
I'm wondering if anyone has tried a hard foam instead of wood for filler blocks? Not styrofoam, but polyurethane. It's pretty hard but fairly easy to shape, withstands heat and chemicals (epoxy) cuts with a blade/saw/hot knife as well as having excellent memory. There are 3 densities I am very familiar with

I'm in the preliminary stages of MS Constitution and the filler blocks seem like oak or something (j/k) and it's daunting. I don't think it's balsa.

Also, is it the norm for manufacturers to fold plans 4-5 times? Mine are creased a bit and for the $$$ I was expecting a wee bit more. Maybe not mylar plans (which is what I am thinking to do) but maybe rolled? Or better yet rolled in a cardboard tube...
This is my second build and the first was MS as well. Just wondering if other manufacturers do things differently.

TIA,
Bobby
Take a look at here

 
Take a look at here

Thank you so much, that's the material. Looking at that image and the way this fine Canadien gentleman is gluing, I'm thinking a hotwire may work very well shaping the foam. Glue it in place and ride a hotwire along the bulkheads on either side to shape/fair it. Might work on easy to get to "flatter" shapes. Just got the idea from that pic so thanks again. Also to the guy who posted the log as well!
Hey, wait a minute...

Cheers,
Bobby
 
Thank you so much, that's the material. Looking at that image and the way this fine Canadien gentleman is gluing, I'm thinking a hotwire may work very well shaping the foam. Glue it in place and ride a hotwire along the bulkheads on either side to shape/fair it. Might work on easy to get to "flatter" shapes. Just got the idea from that pic so thanks again. Also to the guy who posted the log as well!
Hey, wait a minute...

Cheers,
Bobby
Hi Bobby,make sure you are using as glue foam safe CA or regular wiod glue,by the way I am the builder of the Ontario ,thank you!
 
I saw your Ontario and the scale as well. I tried to make joke.

I didn't read your whole thread (for now), and I did see a few posts. That's a nice looking ship.

I'll stay way away from CA, hopefully. The only time I used the foam safe it required a foam safe accelerator to set it off and doesn't seem ideal. Miss a spot with accelerator and the CA on the mating surface doesn't cure with the stuff I used.

I think I'll glue it in with an industrial epoxy, keeping it neat. We do it all the time at work with no wuccas.

Sail hard,
Bobby
 
I use the stuff that you get at arts and crafts store. Not a styro foam, they come in various preformed shaped like balls and cones etc.
 
I’ve experimented with dense foam called ethafoam. It is mostly used to pack fragile objects. Much more dense and resilient than styrofoam (the cheap stuff mostly used as packaging).
As for plans, the only manufacturer I know of that packaged the plans rolled (and inside their own box) instead of folded was Euromodel (sadly gone out of business recently). Maybe there are others?
Stay safe everyone!
 
Euromodel still in business,they just had some issues,also you can order ship plans from cornwalmodelboats,I think they roll them but an enail or facebook contact will solve the problem
 
My thought is to keep in mind the purpose of filler blocks...that is to provide a properly shaped solid surface to glue planking upon. So whatever we use for the filler blocks they need to accept wood glue or CA to hold planks down and not have the plank lift away from the block. For example, make sure CA does not dissolve the foam. If the material you choose works then go for it.
 
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You could also consider the foam blocks that are sold for routing and milling applications. Can’t remember what they’re called but sign supply companies carry the material. Easy to shape and doesn’t create a lot of dust, different densities available. If I find more info will post it here. It’s called “sign foam”.
 
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