[Coco] Cleaning Coco disks (gene heskett) (Andrew)

[Andrew]

All,

Thank you for taking the time on this.

@Bill Pierce: While that is a drive cleaning kit, it looks like it was 
made for 3.5" floppies; I was thinking a 5.25 floppy kit, but I'll stick 
to gene's advice on avoiding such disks for any drive as too abrasive 
(which is what I've heard about them). Maybe such a kit could get me the 
alcohol (maybe Fry's Electronics has something in MG chemicals section - 
I see the MG offers 99% pure isopropyl, which I think is the same that 
you see in video/tape cleaners?). Thanks for help.

@Robert Gault: As noted above, I'll keep the advice on cleaning; I'll 
also avoid trying to align any of the drives, since I certainly don't 
have any of the special alignment disks (I was kid when I remember 
seeing them advertised though). I had thought the disks had a strobe 
pattern on them, but you say that's one the drive - ok. What would be 
the best way to set this speed to 300 rpm? I seem to recall something 
about using a fluorescent lamp to do this from somewhere - something to 
do with the 60 hz flicker? I've got an AKAI turntable that has a speed 
adjustment system like that - it uses a small neon lamp next to the edge 
of the table, and you adjust a little potentiometer to vary the speed 
until the pattern holds still. I assume something like this is also done 
with a floppy drive...?

@gene heskett: Is the "paint thinner" alcohol (menthanol, I'd imagine) 
more-or-less as good as anything from MG? I'll definitely look into 
those swabs as well; I have some acetone meant for cleaning up a 
mini-mill (something I have vowed to get to this year - its been sitting 
in red-grease for a couple of years now with a bag over it) - and such 
swabs might come in handy for that as well.

That head-stepper circuit sounds like it would be interesting to build; 
but I guess I would need a calibration disk to see the track signals on 
the scope, right? I do know how to use my scopes (one's a Tek 2213, the 
other a Fluke PM3380B Combi-scope), though they don't see as much use as 
I'd like (I happened across each in a "right price at the right time" 
kind of moment). I'd only need to know -where- to hook the probes up 
(the Trk0 detector would be easy - but where to read the head signal 
from, off the top of my head I would imagine some test point on the 
drive - maybe it's clearly marked?). The scope traces might be 
interesting to look at - but still, I'd need one of those special disks, 
right?

Probably not possible - but could such a disk be made on a drive (with 
the CoCo or a PC, maybe) that is "known good"? That sounds daft to me; I 
wouldn't expect it to be useful for "exact" calibration, but could be 
used for "close enuff" calibration...?

I do remember ads for those calibration disks you speak of from Dyson, 
but at the time I was a kid, and my parents weren't going to buy me 
something like that (not that I'd have had a clue then how to use it).

I don't know if I would have gone to such trouble for a CD-ROM drive, 
unless it was something that would only read certain disks, or I was 
flat broke; I would have probably tried something from Fry's Electronics 
(at one time - not sure if they still do - they sold belts and other 
parts for VCR and cassette repair), or something from a surplus dealer; 
maybe even tried a belt out of another broken drive (I keep a few around 
my shop now - for what real reason, I don't know).

Usually, when something on my computer breaks, I try something out of my 
shop if it will work (I have ton of PC computer parts), and if not, time 
for an upgrade (bank account allowing) - ;)

While I have Roger's DrivePak and SerialPak (future-proofing my system, 
I suppose?), I figure that whatever I can do and learn to keep the old 
floppy era around (and my drives working) is worthwhile.

Thanks again everyone for the advice.

-- Andrew L. Ayers, Glendale, Arizona