Mold Releases

[Kate Testa]

Hi, Just looking for some info on mold relases... i've never used one while hot pour casting, but have been having some problems with glass sticking to our steel mold. Any sugguestions??? would graphite or silicone be a possible solution??
Thanks

[Pete VanderLaan]

Have you tried acetylene carboning of the mold with a torch? Boron Nitride also comes to mind.

[Tom Fuhrman]

polish the mold or have it chrome or nickel plated. also contact Renite and see what they recommend for your application.

[Allan Gott]

Glass sticking to steel = overly hot steel

Can you get your casting out of the mold any faster? allow the mold to cool a little more between pours? have copies of your mold made so you can maintain your pour rate and rotate the molds?

Renite is a good suggestion. They'll send samples of their spray product which is way better than any graphite spray you'd buy in a hardware store.

[Ted Trower]

Ran across this web page a few days ago. Why do I get the feeling that it's expensive stuff??

http://www.esk.com/en/products-brands/products/release-agents-lubricants/boron-nitride-sprays/glass-industry.html

[Kate Testa]

I'm not familar with Renite, what is it, is that teh company or the name of the product??

[Glenn Randle]

http://www.renite.com/index.htm

Here's the addy. They make graphite mold releases.

[Kier Lugo]

pete mentioned boron nitride. ZYP makes a boron nitride in a spray can that i have used before and was very impressed with. we were casting into steel molds to make small discs 3" X 1.5" i think. the glass never sticked to the mold and we were making a lot of them very quickly. we had maybe 3 of these molds and would get quite a few castings before alternating molds. it only takes a very thin mist to coat the mold (better tobe conservative) too much will cause flaking of the product onto your glass. i think i remember it costing about $40.00 a can, but a little goes a very very long way. we probably did a hundred or more before recoating the molds (or maybe it just felt like that many).
any way, i thought it was a cool product, but certanly not the only option. if you have an accetelyne rig around try that first before buying anything. graphite can be good, but i am not aware of a silicone mold release that would take the heat. good luck

[Kate Testa]

I looked into that ZYP spray and it seems pretty good! were you coating the mold while they were cold or hot? They say that it is flamable and i dint know if i would need to be putting it on a cold mold. do you know if it makes a diffrence... im going to give it a try and see what happens!! Thanks!!

[Holly Wallace]

We coated the steel molds when they were cold- just a very light coat- it hardly shows up but works great. Like Kier said, it lasted a long time.