Two Piece Pop Molds

[rixon529]

I have a couple of baked goods cooling racks for drying of plaster molds. Like Pitbull stated, it allows air circulation all around...

Here's a quote from plaster dot com, the US Gypsum website, about drying of plaster:

"The main physical limitation in drying a plaster cast is the maximum termperature at which the dryer can operate and not calcine the cast. Recommended temperatures are 110 to 120* F for USG White Art Plaster, No. 1 Casting Plaster, Moulding Plaster, Pottery Plaster, Hydrocal Brand White and Hydro-Stone Gypsum Cements; from 125 to 130* F for Industrial Plaster PC. Operating much above these temperatures will result in surface calcination; that is, surfaces of the casts, especially those in front of hot-air ducts, will become soft and powdery."

I recognize that this is written from an "industrial" perspective and not everyone uses a heated or mechanical dryer (or an oven), but in principal, I prefer to err on the side of caution and follow the advice of the manufacturer of the mold medium (plaster) to keep drying temperatures down even if it takes a little longer.

Rick H.

SE CT

[Vodkaman]

I based my PoP dryer on this article. 3x100W bulbs and two axial fans to drive the air around. Having moving air to pick up moisture from the surface, cuts drying time significantly, even without heat.

Dave

[chachybaby]

wow.. good stuff guys. Very good, I'll be keeping this in mind

[Munkin]

OK. this is not a PoP mold but you will get the idea of what an undercut is from this video, and by the way outside of the New York accent this is a good technique with fiberglass resin.

I used this method and my second half of the mold is drying right now. No ten pound bass killas though?

Allen

[dat]

I have never had to sand any of my 2 part POP or DWP molds when making them with the bait being copied inserted half way in the first half. I don't even take it out until the second pour is complete and set up.To each his own.

[dat]

I use a counter sink bit in a drill to make 2 or 3 depressions in my first half after it has cured some, to make lining uo both halves when pouring a snap. Hope this helps.

[Saugerman]

I still, just use marbles in the first half,works great,and very simple.

[chachybaby]

for mine I used 2 inch bolts in opposite corners. Grinded down the heads to make them flat, secured them and poured. Second half had the indents from them. Mold locks up great so far

[t-billy]

I bake mine on the oven rack at 250 or so for several hours to dry. Never had any issues. Also,use elmers wood glue instead of white glue to seal. You'll get a nice ceramic like finish with one coat. I use a roughly 60% water 40% glue mix. Coat the entire face of the mold and let soak for 15 min. or so. Then drain and blow excess glue out of the cavity with a straw. Bake at 150 for at least an hour to dry the glue. It's important to use ELMERS wood glue. I tried another brand once and the finish wasn't nearly as good.

Edited November 13, 2011 by t-billy