Clarification on Foam core ?

[RosieSunshine]

Long time no post,

So I've been thinking of the advice I got from my last post and would like to try using foam core for my house, but the more I read the more confused I get.

So here's what I understand:

1.  Foam core, foam board, and gator board are three different things.
2. Gator board is more sturdy than foam core
3. Foam board has no cardboard or paper sandwiching the foam
4. All three need pins to help the hold
5. Foam core and board will warp when using tacky or elmer's glue
6. All of them take practice to cut well.

However I see people talking about using elmer's glue or other white glue with foam core without warping. Is it a matter of luck? Thickness of the material? Whether it is sandiwiched or not? Are pins mandatory?

What are the pros and cons of the three versus other materials?

[shannonc60]

I’d use gator foam for a structure every time. It’s light, sturdy and comes in thicker sheets. I haven’t noticed mine warping and I have had mine in my workroom in large sheets standing up for 18 months. Using pins would still be a good idea.

[KathieB]

The pins will prevent any shifting in the joints while the glue is drying and help to assure a sturdy structure. 

[havanaholly]

I think the warping is a possibility when attaching wallpaper or painting one side of the foam core or whichever of the materials that has the paper coverings.  If you're gluing foam to foam warping ought not be a problem.

[Sable]

Prime both sides at the same time to prevent warping.

[MaryKate]

Re: Cutting: I've never worked with gator board, but with foam core (which I've used for a 1/4" scale house and other craft projects), I had no problem cutting it with a craft or utility knife. I sometimes have to go over the line to cut more than once to get a clean, steady cut, but I haven't had issues with making exactly the cuts I want using those simple tools.

[Mid-life madness]

I found this handy system at Hobby Lobby by Foam Werks. It is really helpful for getting nice, neat straight cuts, plus you can also bevel the cuts. I bought the guide rail and cutting tool at HL and you can use the coupon for 40% off.

[Khadi]

I've used a hot knife to cut foam core.  I use a metal ruler to help me get a nice straight, clean cut.  It will make the foam a little brown though it you hold it in one place too long.  Assuming you're covering the foam, the brown is easily covered.

[Khadi]

4 hours ago, Mid-life madness said:

I found this handy system at Hobby Lobby by Foam Werks. It is really helpful for getting nice, neat straight cuts, plus you can also bevel the cuts. I bought the guide rail and cutting tool at HL and you can use the coupon for 40% off.

This looks very handy and not very expensive.  Thanks for sharing.

 

[havanaholly]

I use a steel straight edge and a utility knife with a brand new blade, and several gentle cuts, straight down.