Foam insulation seems

You can try painters tape to seal your seam. Paint and ground cover will camouflage it.

I am assuming you are talking about seams on pink board laid on a table. Mentioned was taping the seam then covering with scenic material. I have found that seams have a tendency to crack. I had one place that was a wooden seam and I had it covered with drywall plaster. When I redid my scenery I used Gypsolite and after a short time it cracked on the seam. I think the best thing to do is cover seams with scenery if possible.............Paul

I've had better luck with caulk, its stays more flexible than the tape/dry wall materials.

Scotie

I used mesh drywall tape covered with a skim coat of strucolite.

I used a roll  of 1"  Green painters tape on my last 3 layouts. Worked well and was painted when the foam boards were.  No Problem at all.  And very inexpensive.

good advice all, thanks.

Just realized I have a roll of Tyvek tape from another project, I suspect that would work just as well. Thanks for the tip.

Seams like a good idea.

Two thirds of a pun, P.U. 

Painter's Tape works just fine.  If you actually want a volume filler in case your seams are uneaven, I go with sculptamold.  Great stuff for filler, mountains, roads, etc.

Hhhmmm. Instead of tape or tape over the sculptamold?

I used fiberglas mesh drywall tape--don't crack.