tad Posted January 21, 2007 Report Share Posted January 21, 2007 Why is the second half of my 2 part POP molds getting several bubble voids in them. The first halves are fine. Thanks for any help you can offer. tad Quote Link to comment Share on other sites More sharing options...
nova Posted January 21, 2007 Report Share Posted January 21, 2007 Could be a couple of things. You may be putting too much "release" on the first part and it could be the type of release you are using. If you are using an oil; let it sink into the plaster before you pour the second part of the mold. Don't forget to wipe of any oil that is on the master you are copying. I don't use Pam as a release because of the bubbles it makes when you spray it. I just use a cooking oil, and not a lot of it. Hope this helps. www.novalures.com Quote Link to comment Share on other sites More sharing options...
tad Posted January 22, 2007 Author Report Share Posted January 22, 2007 Nova, I'm using petroleum jelly sparingly. Any thoughts, thanks........tad Quote Link to comment Share on other sites More sharing options...
rixon529 Posted January 23, 2007 Report Share Posted January 23, 2007 Tad: Here is what has been previously posted about this that I could find to help you: " Many people attempting to make a 2-part plaster mold complain that the first half comes out great. Then the second half is full of air bubbles. Here is a method to help combat those pesky bubbles: Try taking a paint brush and painting a layer of plaster onto your model instead of just pouring it over it. After you have brushed on a good layer pour the rest of your plaster slowly and into one corner of your mold box so that the plaster slowly rises over your model. Make sure not to pour plaster directly over model because it can trap air! " Also: " Its likely you will create most of your air bubbles when mixing the plaster, so slow stirring/mixing without lifting the mixing tool out of the plaster will help as well (the more you raise it up and down, the more air gets pushed into the plaster). " And finally: "I seen a guy use a nifty trick to help remove air bubbles from his molds. He took a jigsaw & removed the blade, then clamped the jigsaw to his work surface & ran it a few minutes after pouring the mold. the vibration helps work the bubbles up & out of the plaster. " Hope this helps. Good luck. Rick Quote Link to comment Share on other sites More sharing options...
nova Posted January 23, 2007 Report Share Posted January 23, 2007 Tad; use veg oil instead. PJ will make high spots. The veg oil will soak into the pop and shouldn't make voids unless you put too much or don't wait long enough for it to soak in. You will have to pry the 2 parts from each other gently with a kitchen knife. Don't use a sharp knife as the 2 parts sometimes will break away from each other quite quickly and if your hand is in the wrong place you could do yourself some damage. Give it a try and let us know. www.novalures.com Quote Link to comment Share on other sites More sharing options...
tad Posted January 29, 2007 Author Report Share Posted January 29, 2007 Nova I tried soaking the cooking oil in and couldn't get them apart. Guess I let it soak too long or didn't use enough oil. Rixon529 I'll give your suggestions a try also. Thanks guys. Quote Link to comment Share on other sites More sharing options...
