6 replies to this topic

[Rebel2345]

I tried my first yesterday in hopes to be able to do some injections as well as hand pours, but I ended up with a lot of bubbles in the top half.

What I did was pour my PoP into my mold pan, and stuck the baits in and a couple marbles for locator pins (Thanks to someones top on here).

For my open pour molds, I use Pam as a release and it works great. I sprayed the first half of my two piece and noticed it soaked into the PoP, I didn't think I should use it or I'd end up with some baits trapped in one big piece of plaster. So following a write-up I've read, I used Vaseline as a release between the molds and poured the second half. I had a LOT of bubbles coming up after I poured it. It seems something I did was causing it, so I just let it be until I could see what the damage was.

I had some major bubbles in the top half, I'd call them more like tunnels, or cavities. I've already filled them and it seems like its going to work fine (as far as I can tell), but I'm curious what may have caused this? I'd like some pointers before I try to pour another.


I've tried to search on this site, but it seems I'm doing something it doesn't like. I can search one words but two words makes the search function mad at me

[SHK]

you need to seal the POP before you can pour it. elmers glue/water mix (50/50) or thinned epoxy.

[Rebel2345]

No, this is about the PoP mold itself, not pouring the plastics.

[bassman2169]

Had something similar happen to me when I first tried pop molds. My problem was not mixing well enough. I had some fair sized "tunnels" from the dry little lumps of pop. When it wasn't mixed well, the lumps trapped air and as the pop dried, it absorbed the lumps and left the air pocket or tunnel making a void. I use a wire whisk to mix it up thoroughly and solved the problem. That said, my pop molds seemed too brittle, so I switched to rock hard water putty (advice from a feller on the forum) and have made excellent and durable molds. I hope this can solve your problem. Joey

[bassman2169]

Sorry, need to add a little. The vaseline won't cause bubbles, but when mixing, if you are mixing it like you beat eggs it can also fill the pop mixture with air bubbles. When I used the whisk I mixed slowly, kinda mashing it against the sides of the bowl to remove the lumps and to try not to aerate it too much.

[Rebel2345]

Thanks Bassman, that seems to have been what was going on. I tried another one, stirred the PoP more thoroughly, but slower and I didn't have any major bubbles come up. I hadn't had that problem before so maybe I was just rushing myself.

[Vodkaman]

I use a floor wax. This prevents any air from rising from the first half, but Vaseline does the same job. I mix the powder and water by hand, slowly, to avoid bubbles. This will make your skin dry, so some skin cream when you are done.

Do some Google searches, lots of really good expert information out there, well worth reading.

Dave