There's always part of me that's surprised that enameling works at all given the difference in thermal expansion. Though the lower thermal expansion of glass would leave it in compression, so there's that. I know with pottery finding a glaze chemistry that fits a clay and firing level is empirical or trial and error. Sounds like enameling is similar and the well known artists are guarding their knowledge.
You gotta glaze the back, too. It works like this: 1) Get a chunk of copper or silver or gold 2) Get it to shape and thickness 3) Flip it over and put your scraps and spillings on the back (traditional) or get some nice lookin' opaque solid color (artistry) and bake it 4) Cool it down, flip it over again and put a layer of clear on and bake it 5) Cool it down and bend fiddly little wires and glue them down with a slime made of lily root powder and bake it 6-a lot) put colors in and bake it I dislike the inexactness of (5) so I've blown like $20k to carve a solid billet rather than get out my tweezers and goo. "tweezers and goo" is definitely a whole bunch of the artistry involved but it isn't fun to me. And yet somehow "huh I need to design a mount for an NPN sensor over a trigger on the ATC to talk to the ECM to talk to the motors to talk to the pneumatics so my LUA code will correctly execute 35 steps to change a tool" is more fun. (6) is fucking fun.
You made cloisonne sound approachable until I counted and it's got to be cooked 4 times. Your mill project has been fun to follow. I knew a guy who made some upgrades to a CNC router he bought but nothing close to the precision and ambition of yours
Oh it's hella more than 4. The people I learned enamel from who didn't understand enamel said the more you fire it the more the colors wash out, but that's probably bullshit Thompson enamel which doesn't include all the wonderful cadmium and other toxic heavy metals. Last enamel project I did fired like 16 times? But it's not a big deal. You fire up your kiln, get out your trivet, get the temp to exactly what it oughtta be and then slide it in there for two minutes and fifteen seconds and you pull it out. That part's pretty chill - it's the bendy little wires that are aggravating because you wanna get 'em exactly right and you have to bend them with tweezers and if they move while you're firing (if the glacier shifts, really) you're fukt and every imperfection you made while you were bending them becomes increasingly annoying with every subsequent firing. My buddy with the real CNC machine called me up yesterday and said "what order do you want these parts in 'cuz you got a backlog. You're making progress by leaps and bounds and I don't wanna hold you up." Nicest thing anyone has said to me in weeks.
Oh that's not too bad if you can get multiple firings in a session. I was assuming the whole kiln has to cycle up and down like with pottery
Yeah that would be untenable. here's the basic enamelist's kiln. I have one. They're great; you can use them for burning out wax and melting glass. That li'l "bead door?" Yeah you flip that open, slide your spatula in there, stare at it (with glaziers goggles on lest you..."fog your windows") until it's properly melty and then pull it out. I timed it; the melt/cool/paint/remelt cycle can be accomplished in about 20 minutes on a watch-dial-sized item. I got these down to about two hours each, integrated, of which an hour each is the fiddly little wires.