On Mon, 24 Nov 2014, Jules Richardson wrote:
40t 5.25" drives are not particularly common
these days, though. Available
for $25 or so via various channels still, it seems, but they're not kicking
around in hardware that's destined for recycling like they once were. I see
the odd 80t drive (once or twice a year) but of course they're useless for
writing 40t media.
When used with virgin/degaussed media, they CAN make a usable disk, but
the original poster needs to reduce the number of variables, not increase
them, so they would certainly be not recommended.