Ok. I currently don't have any used microwaves to take apart but next time I do I'll look closely. Fortunately I did all this outdoors and only broke open a few emitters.
I carefully took the ends off a couple emitters to see inside as I was very curious as to the construction.
Many of the microwaves I see tossed to the curb in residential areas are not even in that bad of condition. Maybe a fuse out or something.
The smaller ones that don't have the plate with the cog on the bottom, those are the best plates to use for eating. The ones with the three lobed cog are no good since it high centers. It's a shame to toss them in the trash.
If you're not suffering from any respiratory problems, you probably didn't inhale any BeO dust (or enough to do any damage.)
Modern microwaves with electronic control boards use the absolute cheapest shit relays for power control that they can get their hand on. When I did appliance repair for a company that has a round logo, some of the newer boards (mid 90s) that Samsung provided were made with cheaper than chips relays. They were uncoated copper contacts and would just arc and burn closed or open, and you'd lose the device. No batch of these parts had the same name, everything from "Yung Reem" to "Bright Star" was stamped on them. We heard rumors that these things were made by whomever won the contract that month.
Funny story, my boss talked to the engineering staff at Appliance Park that approved these. They said "Well, we tested some relays and they worked fine!" Boss goes "Did you buy them from a commercial supply house?" Nope, they were samples from Samsung themselves, hand picked and massaged to work the best.
Hey, thanks for the assurances. After I found out about the beryllium and remembering the precautions we took at the processing factory I was a bit alarmed. I tossed all the emitters I had left, damn the copper and vowed to not open up any more until I had more information.
Yes, I noticed the cheap safety cutout switches and stuff. Those things are uber cheap made with the bare minimum of circuits needed. After I took one capacitor apart not knowing the composition of the coil I just noted how quickly it oxidized and tossed the rest as I had no plans for them. I saved out all the transformers because I wrongly believed the windings were copper but unfortunately, all I have checked had aluminum windings.
I needed the copper windings as I was searching for suitable sized copper wire to use in jewelry wire wrap.
The one thing that has irked me is that even after carefully straightening what copper wiring I did get from windings around little feroceramic devices there is a pesky varnish I have not found a solvent to clean it off. With the varnish I can not use an oxidizer to blacken the copper for jewelry. If you know how to easily dissolve the varnish on copper wires I would love to know and be very grateful as I've found no source online explaining this. To get the varnish off I have carefully heated coils over a gas burner and then sanded off the carbon and have just used fine grit to sand the wires.
I will say, the coils around an old picture tube from a cathode tube TV are excellent wires. The fine windings I discard as I have no smelter but the heavier windings from the tube are perfect size. Since I'm stocked up now I quit searching out microwaves and am now focused on processing the copper wires I have.
BTW, the new flat screen TV's have little of value in the way of wires or gold fingers.
I did manage to get an old plasma flat screen, very large and almost too heavy to carry. On disassembly I noted that the base was heavy steel for weight but inside were hundreds of connections with gold plated fingers. I saved all the fingers from the many circuit boards and found some interesting wires. I had about eight ounces of fingers, maybe a couple hundred bucks of gold plate and then one of my "friends" managed to sneak off with it when my back was turned. The backing for the display was thick aluminum plate with many aluminum posts riveted into it for the circuitry in the back. That thing was built like a tank with heavy glass plates for the display parts. The new TVs have plastic sheets to disperse the lights from the LED backlights and for the display. Very interesting technology.
Yes, wire around the neck of a CRT is called the yoke, it's what generates the deflection that allows the electron beam to scan across the tube. They should have varnish on them as well, but the type varies based on manufacturer. Transformers also use varnish insulated wire, as you found out.
As far as getting it off, in electronics we usually just burn it off with a torch. Acetone may work on some, Dichloromethane may work on others (paint stripper.) There's no real universal answer, it depends on that manufacturer's formula, but what you're doing now is how we do it when something needs to be soldered to that type of wire.
You may be able to find fine copper wire in other places. Old telephone lead-in cable (not handset stuff) was often small gauge uncoated copper. Some CAT5/6 cable is uncoated solid wire. Radio Shack used to sell paired solid 24GA uncoated copper wire on spools, sometimes you can find that at shows that no one wants because the copper has oxidized. The center conductor of coaxial cable is often uncoated 24GA copper.
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