[Archive] warping foamcore?



I’ve just noticed that the walls of a tower I built are warping. Given the direction of the warping, I suppose it must be be to the amount of glue I used, as the hundreds of bricks were all individually textured, cut and glued in place.

Here’s the question: How can I stop it? Should I make all the walls of structures twice as thick by hot melt gluing another sheet of foamcore to the back side?

I’m planning on making a structure with a removable roof and painted inside, and really want to avoid having the walls warp.

Any advice would be appreciated!


You could try bracing the opposite side of the glue joins. Try gluing bits of plasticard on the back, or cut channels into the foam and apply the bracing there.

Warping is a big issue when preparing masonite for painting and the general solution was after you paint the gesso on one side, you paint an X of thick gesso on the other side. As the material dries it shrinks and the tension pulls at the corners and because its relatively equal on both sides, it would eventually become flat.

I’m not sure these will help you, but maybe they’ll suggest an idea that does to you.


Well, I’m planning on using slats of wood (read: distressed and cut-to-size Starbucks Stir Sticks) on the outside.

One thing I just thought of is buying a sheet of plastic that’s about 3mm thick and using that as a backing. I found out that you can buy sheets of plastic at RONA, which are normally used for covering florescent light fixtures. Might be a good solution, but the cutting might be difficult. Plus, I’m cheap.

Alternatively, do you think what I suggested above would work? It may be the most cost effective solution.

After all, I wouldn’t want the walls of the Whateley farmhouse to warp…


I wouldn’t use whole sheets to back the foamcore, as you’ll need more glue to put it on and that will warp too. The stir sticks sounds like they’re you’re best bet.  As for the plastic - sheet styrene isn’t that expensive and is very easy to cut, so my bet is still on that. You can buy it pretty thick.  

How big are you building this thing??

Also, on my travels I found this:


Looks okay and it should scale okay for 25-28mm terrain, I think. It stands 8.5" tall and is 1/87 scale, supposedly, but from looking at the pics online, those numbers don’t make sense to me. Might be a tad small in the doorways. You should do some research on it if it appeals to you.


I’ve done some rough doodles - I think that a size of about 10" (depth) x 14" (length) x8" (height, plus roof peak). I’m also planning a covered porch which wraps around two sides of the structure… Although, I think I’ll find a copy of ‘The Dunwich Horror’ (1970) to download and watch tonight for some more inspiration. Dean Stockwell rules. I might cut some old boxes apart to try to see if the size is really correct, and leaves enough room inside for the Threshold agents/Investigators to move around.

Maybe if I made some kind if ‘chair-rail’ woodwork on the interior walls it could help prevent the warping. However, I want to make the exterior planks run vertically, so that may be a problem. What about the adhesive drywall mesh-tape? Maybe I could just cut that to size and place it on the foamcore I’ll be using for the walls, and use that to put the planks on top of that. I’m pretty sure it’s adhesive on both sides, so that may solve the glue/warp issue as well,and with the chair rail woodwork inside and some drywall mud to simulate plaster, that just might work. And, as there will be floors, those will help with the rigidity. Maybe some balsa ‘roof beams’ could help as well. although they may make moving things around inside difficult.

It’s a really ambitious project, but I’m really excited to get some ‘pulp/Call of Cthulhu’-style scenery built. My wife suggested an asylum, but that would be even more ambitious than this! I’ve had no luck coming up with an Innsmouth Waterfront schematic. However, I did manage to find a place that sold a cool-looking ‘Cthuloid’ miniature: http://www.mirliton.it/product_info.php?pName=hell-beast&cName=nightmares-28mm

However, I’m putting any miniature purchases on hold until I finish a bunch of scenery to use them with. Things are really tight financially around here, and I know I can get lots of projects completed with a very small investment.

Thanks a lot for your advice - it’s much appreciated!


Here are some great paper models which can be downloaded - might be a quick and easy way to get the proportions right…
Phantom Manor Paper Model kit


I’d use maybe 2mm styrene/ plasticard.  I really can’t see that warping.

If nobody is going to see it you can cut thick plasticard really quickly. Score it a few times, using a metal rule over plastic ;), then bend and snap. Mostly it makes quite a clean break.


I saw this at the hardware store, and think it just may work…


~2’x~4’. approx 3mm thick… for $16CAN? Might be worth checking out…


Apparently, it’s quite brittle - but that’s good. I may pick up a sheet tomorrow. Now, the big question: How can I get things to stick to it properly? For example, I can’t really just smear some drywall compound on the plastic and expect it to be secure… Maybe mesh tape the interior and exterior walls? Thoughts?