An 8 Inch Disk Lathe

I have a Tandon TM-848E 8" floppy drive which appears to have become a disk lathe. Or perhaps just an effective disk eraser. It's one half of an external dual 8" drive unit that I picked up off eBay several months ago. I've cleaned the heads, and I can't see any sharp spots or debris with my head-mounted magnifying lenses, but it continues to scrape rings in the oxide of a disk on both sides. I haven't tried removing the heads to put them under my microscope since that would destroy the alignment. I've only tested it with the pair of disks that came in the drive so far. It's possible that they are bad disks with soft oxide, but I haven't seen the same scraping problem so far in the other drive of the pair. So, that one drive appears to be a disk lathe now. I haven't felt up to risking a potentially good disk in the bad one. Have any of y'all seen this kind of problem before? Is it likely to be repairable, even if that involves removing the heads and then realigning the drive when I reinstall them? Or is it most likely that the drive is fine and I've just been putting bad disks in it? I don't have any alignment diskettes yet, but I may get some one of these days. For the time being, I'm assuming that I'll just use the drive as a source of parts for other TM-848-series drives in my collection, like one that I have with a broken latch handle. The other drive plus the enclosure is earmarked for use with my KryoFlux. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/