Struggled with a color casing for three days straight

Tried to case a cobalt blue rod with a transparent amber last Tuesday. The amber kept cracking off in sheets the second it hit the marver. Figured it was a heat issue, so I tried slower heating, faster heating, even used my old Carlisle glory hole to pre-warm the amber. Nothing worked. Wasted about $60 worth of color before I called my buddy Mike. He asked one thing: 'Did you check the COE?' Turns out I grabbed a 96 COE amber from a mixed batch, trying to case it on 104 cobalt. Felt like an idiot. That simple mismatch cost me a whole project timeline. Anyone have a good system for keeping your COE batches sorted in a small shop?

3 comments

3 Comments

diana_murphy2mo agoMost Upvoted

Honestly, I don't even label my COE anymore! I just mix and match based on how the glass feels in the flame. Sometimes that tension makes for a really cool crackle effect you can't plan for. A strict system takes the fun out of it for me.

emma_dixon702mo ago

Sounds like a good way to end up with a pile of broken glass.

adamk952mo ago

My friend's whole kiln shelf cracked from mixing COE like @diana_murphy, so I just use colored tape now.