Cast resin rank insignia

Hfuy

Hi,

I'm casting some rank insignia in resin. Strictly speaking they're Bath stars, as used by the British army to indicate rank. A captain has three, for instance. Here's what I've got so far:



At the back is the latex mould (I'd have used silicone for anything bigger), and below is a freshly-cast pull from that mould, one that's been finished and painted, and a real original brass star from which the mould was created. That's a 10mm grid, so the stars themselves are about 18mm or 2/3" square across the points.

Although this is going reasonably well, I have two main problems. First, I'm casting these in epoxy adhesive because I happened to have some lying around. I'm not aware that epoxy adhesive is in any way different to the stuff you'd get as true casting resin, but they do stick rather. Is the proper stuff less likely to adhere to the mould? Latex is tough, but I'm constantly worried about tearing the mould apart getting them out. Are there release agents I could use? Any suggestions?

Also, bubbles. I know bubbles are the scourge of resin casting, even at a quite high level, but I'm not aware that there's any real solution other than a vacuum chamber - and I don't have one.

Any pointers gratefully received!

Best,

HF

Attached Thumbnails

 

jedimaster

I had to make a ton of these and uniform buttons for a ww1 flick. Urathane resin will work the best. Dust you're latex with talc first and when you have poured the resin tap the sides of the mold and watch the bubbles rise to the top. Not sure how you intend to mount them. We just put a u nail into the resin while it was setting. Painted em up and sent em off to wardrobe.

Also you could inject the resin. Or pour down one side of the mold and let it fill instead of just filling. That way OT should for e the air from the mold and reduce any bubbles.

Hfuy

Crikey - talc? Really? I'd have thought it'd make a terrible mess, but OK!

Nice to know I'm not alone on the bubbles.

Tria Juncta in Uno, etc.

HF