Resin Issues

Hey guys, I'm a newbie when it comes to RTV and resin and I'm having abit of a problem. I have a one part RTV mold, and when I pour the resin to the brim as it hardens it expands for some reason. Then when I pull the part out the underside is all whacked. Any ideas for a fix on this?

Thanks

I think its not expanding, i think your mold is deforming.

Can i see a picture of your mold and mother mold? How big and how much weight are you talking about.

In my experience. if the mold isnt at least 1/4 3/8 of an inch thick in ALL spots. it will buckle.

try roto casting one (fill it half full and just swish it around, pop it out and see if thats deformed.

Also, what resin are you using, GP or Polyurethane?

DAZ

No see the Polyurethane resin is coming out the top of the mold.

Where did you buy your resin?

Its from a company named Vagabond. I bought it a few years ago. Could it be expired?

Its expired. its foaming

When water gets in the resin, it starts to foam. I dont know why, but im thinking tahts it

I see...What brand resin do you suggest? Since I'm in the market.

yeah, that stuff needs to go to your local hazmat disposal center.

i use http://www.reynoldsam.com/ myself. usually smoothcast 32x or roto. the 32x series has different cure times and colors and such, so i get different ones depending on what i'm going to be doing.

btw what is roto casting?

Originally Posted by Walteekin25

btw what is roto casting?

I've just updated the [[TDH Glossary]] with some new terms. [[rotocast]] and [[slush cast]]

Stormrider is right on the money, it's moisture. When you buy some new resin, go ahead and get a can of dry gas. You spray it into your canisters when your done using them, and it helps remove excess moisture.

Originally Posted by BOBA PHAT

Stormrider is right on the money, it's moisture. When you buy some new resin, go ahead and get a can of dry gas. You spray it into your canisters when your done using them, and it helps remove excess moisture.

Of course he is! Stormrider's the man!!!

I use smoothon roto if i want something with a little flex to it, and I use alumilite if i want something rock hard.

Sometimes I use the same cups over and over for pouring resin, and if its a heavy humidity day, my resin will foam on small pieces

Thats why people prefer to make things for people in 'runs' because its not good to have resin just sitting around for months. it goes bad (so does silicon) and its wasted.

I have not tried the smoothcast 32x series, but as stormtrooperguy says above, they take pigments (colors) well (a lot better than the rotocast series) as well as fillers (aluminum or microballoons).