Foam Board Arts&craft Projects- I Have Panels Coming Together at Angles. How Can I Make the Seams Look Smooth?

Question by ChuckBoutwell: Foam board arts&craft projects- I have panels coming together at angles. How can I make the seams look smooth?
Running a strip of tape along the seam leaves a crack visible under the tape. Any filler? Or any tricks or tips?

Best answer:

Answer by Michael P
The best plan is to not cut the board, just hinge it. Basically you cut a ‘V’ shaped groove on one side and then bend the board to close the V and make a corner. The angle at the bottom of the V should be the same as the angle you want the two sides to meet at. i.e. cut a 90 degree V cut, bend, get a 90 degree corner with a nice clean, closed outside edge. It doesn’t take too much practice to get the hang of cutting to the paper without cutting through it.

Answer by DIY Doc
I’ve used “Foam Core” board for many years in both theatrical set designing and architectural modeling. Answer number one has a valid notion, though certainly you should apply the “practice” to as much as you need to “waste” before attempting a seamless “Exterior” corner.

The most obvious/best way this will work is on angles such as what one might find in a box, or walls in a house (90) but can with enough planning work for “Crafting” as well. AND for Exterior views of any project piece

It will be similar to “scoring/mat making/ or even looking at a cardboard box and it’s assembly.

Without knowing at all “what” the projects are, it sounds like you used a clear tape (Scotch tape???) Or didn’t pre finish the butted joints of any two pieces of board. Tape edges would be obvious in any case. Even using Gaffers tape, (Which takes paint well enough) would allow some finish underneath to possibly show.

Foam core is pretty durable, but the “Paper” face is subject to effects of moisture. and to add anything such as Mud or other fillers to a butted joint. might mean sanding would have to be done, which would degrade the smotth face of the paper. Painting foam core, especially the thinner 1/4 or 3/16th thick board will also cause some warping, which is often counter balanced by painting the opposite side as well.

I’d try the scoring/ (V CUT) on the interior face of any design you have, but multiple angles, odd angles that must meet will be a challenge and depend on your ability and skill level also using Geometry principles. Actually if you had a mat cutting appliance/tool you might find better results, than using a Utility or X-Acto knife, a ruler/straight edge/ and the often UN constant pressure one applies by hand in such cases.

In all cases have a Large supply of any blades you choose in your cutting, as they dull quickly at the POINT of any material cut.

Steven Wolf

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