Dense Foam Urethane - Pores! Oh No!

[MjolnirArmor]

I just started messing with the dense foam urethane for guns and stuff to reduce weight. Problem is, the self skinning skin sticks to the mold sometimes, even after 4 hours of curing.

I use the proper foam release agent (spray) and I've tried wax too. Any ideas here? Should I Let it cure longer? I've noticed that it hardens more and more, all the way up to about 8 hours later. (even though it says fully cures in 2 hours)

the REAL question is, what do I use to primer the surface? I paint it with Krylon H20, or regular primer and it seems to make the pores bigger, and castings become pocked. Is there a spray on style sealer for after you pull the cast?

 

[Rogue Studios]

I've heard (keyword) if all else fails coat the mold with a thin coat of latex paint. However I suspect it will bead.

 

[MjolnirArmor]

I was just about to do this... ye old wall paint and a brush :-(

 

[Rhett J Martin]

I've had some (another keyword) success with spraypainting primer right into the mold. I took the cue from REL, who's had success with his fiberglassing.

Best of luck!