mould release agent and slumping question.

[Jules1971]

Hi Guys hope you can help me on this.

so i have bought a few moulds and one of them is a frog mould cot de vere

as i would probably not use it for putting frit in it as it is designed i would like to drill a few breather holes to use for slumping the small green beer bottles and turning into a paper weight that still the outer edges of the bottle as i think it would look rather cool.

i think it would be ok to drill breather what do you guys think?

next i have tried to put kiln wash but it is so streaky it looks terrible is there a spray/aerosol based alternative that i could use for this application.

thanks in advance.

[flame n fuse]

Hi, on the simple moulds that I use for slumping I use 3 or 4 coats of kiln wash, brushed in different directions.
I visit a fb page (fusers of cpi), where there are many complicated pate de verre moulds and notice that people talk about using zyp spray which is boron nitride.
I think there is more info about this on the creative paradise website.
Drilling - should be ok but go slowly!

[Jules1971]

thanks

[GorgeousGlassGifts]

Hi Jules.
Regular batt wash (such as Bullseye shelf primer) is ideal for ceramic moulds. It should have the consistency of full cream milk & you need to stir it between coats, as it settles out. As Flame n fuse has said, apply each coat in a different direction, using a haik brush. I use 5 or 6 coats on a new mould and typically 4 coats when recoating a mould.

If you want to drill a hole in a ceramic mould, I'd suggest using a tile bit if you can find one small enough, & then kilnwashing the mould afterwards.

Boron nitride is a lot more expensive than kilnwash, but comes into its own on metal moulds, to which kilnwash doesn't readily stick.

Let us know how you get on! 

[Jules1971]

Sorry for the long time in replying. In the end went for boron nitride as im pretty paint spraying and i got a better finish. Although for moulds flatter in nature i use kiln wash and sand it down due to it being a lot cheaper.