I resurrect this old thread because I tested a bunch of black lcd with know good logic board and good inverter. Basically I simply swapped the black lcds to a known good combination of inverter and logic.
Lcd recapped but the black syndrome stays therefore it must be something else on the lcd circuitry.
Yes a blasting cabinet is great, but hard to see through after a couple of minutes, it's more a hit and miss game.
Yes again, touching the sandblasted metal with your fingers is not a good idea, the damp skin is to be avoided in bare metal.
I will go for a grey or metal finish, but just my point of view.
Concerning the Retrobrite, i have had better results boiling water first, and mixing it with Vanish on a second time (don't use peroxide anymore, Vanish is more easy to use and do more or less the same trick)
I recently ordered some replacement gears from here:
$8 for 12 parts + shipping
The design is opensource, you can find the 3d files here: https://www.thingiverse.com/thing:4167139
I have quite a few drives I'm replacing the gears in so I'll post my experiences here.
Replaced my first drive a 800k External Floppy P/N 825-1174A that was not ejecting. You can see the in the first picture the state of the old gear, it denigrates to the touch. The eject drive was a OMRON R2DG-31 - slightly different then other ones I've seen, but the internal gears are the same.
The fit is good, you can see the teeth line up well.
The video shows the first few ejects. Note the springs for the top were not attached when I took the video. Also the drive has some noise when spinning, unrelated to ejecting.
So far they seems to work just fine, I've done about 20 ejects and all feel the same. We'll see how it holds up and I'll post here with any updates.
Probably the best option will be to try to have a contact with Adam Goolevitch (Canada) who is the owner of one of the two Twiggy known units.
he was able to revive his own and the other one, has a lot of knowledge of Twiggy drives and Apple Lisas (1).
Has been there, done that...
probably a contact through Cult Of Mac i agree..