foam for carving?

Sulla

Sr Member
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I was thinking of carving some faces from foam for a little project of mine.

I am looking for something hard enough to carve but not something harder than foam, so not the white packing material stuff which is too soft. I want something more dense. Like the stuff used to make terrain for war hammer or dioramas.

Any idea where a chump like me can come across a little of this stuff?
 
I was thinking of carving some faces from foam for a little project of mine.

I am looking for something hard enough to carve but not something harder than foam, so not the white packing material stuff which is too soft. I want something more dense. Like the stuff used to make terrain for war hammer or dioramas.

Any idea where a chump like me can come across a little of this stuff?


I've found some pink/blue foam that is used for wall insulation at my local hardware store. That looks close to the stuff the wargamers make their terrain from, got to be carefull about the dust though, I've heard it can be bad if you breath it in by accident.
 
I get mine from lowes, I like the way the stuff from home depot carves better, but when I show unfinished pieces to people they just can't get past the whole "It's Pink, why is it pink, did you notice that it's pink, the real one isn't pink" I've gotten that enough times that I now no longer buy the pink stuff.

Before you put this stuff on your band saw be sure your table is square. Get yourself a few needle files and a nice small metal file (using a metal file when possible instead of sand paper will cut down on dust) , a few cheap long retractable razor knives and a felt tip marker to keep your center line. If you loose your center line you could end up in a big mess.

Practice pulling the retractable razor knife through the foam at an angle less than 45 degrees. this will give you nice clean cuts that need little sanding or filling. Working is this medium is not for everyone so take some time to feel it out. The two inch thick stuff is cheap enough to wast some in order to get a feel for, or decide you hate it and never want to touch it again.

I'm sharing pictures of what I did yesterday ! Ask question if you get stuck or just would like another pespective.

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I did this in less than six hours, I could have gone faster but I needed to keep checking my calipers and the picture. If you are doing an original piece you don't have to keep checking your measurements. This is the fastest way to make something I know of. Have fun with this stuff and please share pictures of what you make.

There was a bunch of very cool foam sculpture websites I had found about a year ago by doing a google search, and I wanted to share them but I can find them now.
 
Awesome advice.

Thanks everyone for your help! I feel I have enough info to get started.:)
 
I get mine from lowes, I like the way the stuff from home depot carves better, but when I show unfinished pieces to people they just can't get past the whole "It's Pink, why is it pink, did you notice that it's pink, the real one isn't pink" I've gotten that enough times that I now no longer buy the pink stuff.

Do you ever use or have need to use a hot wire when cutting or sculpting or does this foam even take well to that type of cutting?
 
balsa foam is definitely a winner.

it is easy enough to carve but keeps it shape under light to moderate pressure

not as cheap as insulation pink/blue stuff, but if you're confident enough it is a better material.

I do not know how it will react with other materials ie. paint, bondo, fiberglass, caustic 2 part hardeners (plastic, epoxy, etc.)

just be careful to test those materials on a piece before you say, sculpt something..bondo it..and wake up to a horror
 
Do you ever use or have need to use a hot wire when cutting or sculpting or does this foam even take well to that type of cutting?

I've never used a hot wire. I've seen videos and it looks very cool, but you also have the fumes. I like my band saw for the stuff, just make shore your table is square.
 
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Oh some one said something about how it takes to bondo and other chemicals. After your happy with what you have, you have to paint the item with a sealant. I like gripper, it's white and easily sands smooth. You have to brush it on, spray application will eat this stuff if it is not sealed first.

I'm glad some one said something, I forgot to share that. Some one could have made something very cool, then melted it. Sorry.
 
balsa foam is definitely a winner.

it is easy enough to carve but keeps it shape under light to moderate pressure

not as cheap as insulation pink/blue stuff, but if you're confident enough it is a better material.

I do not know how it will react with other materials ie. paint, bondo, fiberglass, caustic 2 part hardeners (plastic, epoxy, etc.)

just be careful to test those materials on a piece before you say, sculpt something..bondo it..and wake up to a horror

I can tell you from personal experience that bondo, fiberglass and anything that involves acetone will attack the pink/blue stuff. I find a coating of five minute epoxy protects the foam from anything you want to throw at it. You can use fiberglass cloth with epoxy just as easily as with fiberglass, but if you use epoxy, you have no "melting foam" problems.

This was a trick I learned from Greg Jien - make the foam piece just a little smaller than you want the finished piece. Coat it with epoxy, then fiberglass cloth with more epoxy soaked in, to just about your final thickness. When the epoxy is rock hard (overnight is good) you can sand it, add stuff to it, cover it with bondo, whatever you want. If you want a hollow piece, make a small hole and pour in acetone. It will eat away the foam. Pour out the acetone/foam liquid and you have a hollow, hard shell piece! This works well for things like spacecraft hulls, weapons, back pack devices... anything you might want to later open up and put lights or electronics in.

Always remember when working with acetone to wear skin protection (even though the stuff is used in fingernail polish remover, you shouldn't touch it if you can avoid it), have PLENTY of ventilation and KEEP IT AWAY FROM SPARKS OR OPEN FLAMES!
 
What about vac forming thin plastic over over it? Like 1mm or thinner?

If I can carve the foam into the face I want and vac form it at least once, I can skip the sealing steps.
 
I've never even tried to vacuum form the stuff, It just doesn't look like it would work. Making a mold and casting it in plaster wouldn't ad to much time to the build. Then vacuum form the plaster cast, But you aren't going to get great detail out of vacuum forming it, and you'd have a mold at that point, so why not just build the mold and cast it in resin so you could get perfect copies ? Are you thinking of using this to do a one off ? If your only going to make one of what ever you are thinking of making this may not be the best material to go with. Or go with the fiberglass thing that Jaruemalak was talking about. I've never done that but it sounds cool if the piece doesn't call for to much detail.

There was a really great website where they were selling a sealant for this kind of work that was really great. I can't find it now and I'd love to put a link to it on this thread.
 
Yeah, just a one-off without a lot of detail. A very simple face to make a mask for my niece to play around with. I figured foam and some of my plastic would do the trick.
 
Zorg,

It is called 'BLUE FOAM' over here.....it's an extruded polystyrene for roof, wall and floor insulation. Same for the pink stuff. I hate it. Low density polyurethane foam is much nicer, just 5x the price :rolleyes.

Try here:

http://www.sheffins.co.uk/

http://balsamart.co.uk/

i knew you would know neil :thumbsup

i cant believe it but a sheffield insulation has just opened in town. woo hoo!

i had a look on the website, not sure what to ask for??

any clues / product name?

cheers

-z
 
Just throwing a little 2 cents in - there's actually a new spray can product by Krylon that is a sealant for styrofoam, but I have used it on the blue/pink insulation foam and it does work (at least I had no problems with it).

They carry it at A.C. Moore's, Michael's, Joann's, etc. In all the stores around me its located in the floral section.

-Kyle
 
Great advice on the balsa foam guys! I used green floral arrangement foam to carve/sculpt the shape and then seal it with Mod Podge before applying bondo to it. But when I vac-formed 1/16th of an inch of HIPS, the buck buckled in several areas. I found that those areas have thin layers of bondo and will need reinforcing. I used a 6.5 hp shop vac for the vacuum pressure.

So, I was adviced to lay on the bondo thicker to make it stronger for the vac pressure. This means that your original sculpt should be a tad smaller than the actual size to compensate for the thickness of the bondo.
 
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