Thread: Silicon casting moulds

You can also get a silicone cooking tray pour your PR do the swirling and then cut into blanks. That way you can also make thin sliver on glass and ad them like a birds nest

Do a web search there re many ways out there and lots of tutorials on U tube

Conduit an also be used on the horizontal centre hole to fill and a track cut the length of the conduit use conduit caps on each end

Originally Posted by joe greiner

Silicon? or silicone? I've fabricated some stuff in silicone (ordinary sealant/caulking) by sort of a lost wax process. I carved a core in paraffin wax, then coated it with sealant, smoothing with lighter fluid (naphtha), which was listed for cleanup. After a few days, I heated it gently to drain the wax through a lower integral pipe nipple. It was a DIY huffenpuffer for a cheapo scroll saw that didn't have a pump. The nipple held a piece of vinyl tubing wrapped with "rigid" electrical wire for adjustment toward the spraying end. I learned about the tennis ball trick afterwards. What about using a "baby enema" Available from chemists. Just try not to think what they are really used for.

Cheers,
Joe

Other thought on silicon molds. how about using stickytape. I do that over my forms when I an laminating veneer. No sticking. Stays put where you want it.

Another thought is those Ice block silicon trays you can get from cooking shops, like the General Trader. Ive even sseen them in the $2 shops. The long skinny ones are for ice blocks to put in drink bottles.

Originally Posted by tea lady

The long skinny ones are for ice blocks to put in drink bottles.

I had the hardest time finding those .. in fact, another turner found them for me and sent
them in the mail. Other people said they are good for casting tubes but I haven't gotten
the air bubbles to clear out of them yet. Maybe it's the distance the bubbles have to travel,
I don't know.

I also had a terrible time getting the resin out, whether Alumilite or PR. And that was with
release, too. Had to use a hammer and dowel .. and that pretty much made the parts
unusable..

But others seem to have done fine with them, so it must be me

Originally Posted by NewLondon88

I had the hardest time finding those .. in fact, another turner found them for me and sent
them in the mail. Other people said they are good for casting tubes but I haven't gotten
the air bubbles to clear out of them yet. Maybe it's the distance the bubbles have to travel,
I don't know.

I also had a terrible time getting the resin out, whether Alumilite or PR. And that was with
release, too. Had to use a hammer and dowel .. and that pretty much made the parts
unusable.. I thought they would stretch off to a certain extent.

But others seem to have done fine with them, so it must be me

Not that I've actually tried it. Might though! Its got me curious.

I'm still very much in the dark about your mould material. The silicone sealant/caulking I mentioned is also available in a high-temperature version for stovepipe encasement. I've made very flexible moulds for casting molten lead successfully; even the ordinary stuff works, but not as well. I haven't used it for casting resin, so I don't know how well or poorly it would release. Sprayed bond-breaker wouldn't hurt.

To cast twelve reasonably identical blanks, it might be simplest to make thirteen or fifteen walls of paraffin wax in a constant thickness, and arrange them to form twelve chambers. If the casting envelope isn't big enough, separate pours might be needed. The wax can be melted for release and re-use. The wax won't begin to melt until the resin starts to cure, so the shapes won't be compromised.

My newer scroll saw has a built-in huffenpuffer. But I'll try to remember the baby enema for any other applications. Thanks, TL.

Cheers,
Joe

Originally Posted by joe greiner

I'm still very much in the dark about your mould material. The silicone sealant/caulking I mentioned is also available in a high-temperature version for stovepipe encasement. I've made very flexible moulds for casting molten lead successfully; even the ordinary stuff works, but not as well.

I'm using special purpose moulding silicone designed for casting resins. I had thought about trying wax a few times, but wanted something more permanent.

Russell.

Thanks for the clarification, Russell. I guess you have it under control. I have too many other dead horses to beat, so I won't need to beat this one.

Cheers,
Joe