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Fire-Flare
October 24th, 2017, 02:27 PM
I have an Osborne 1 that won't boot from the A drive.

I did the 'boot from B drive' trick and it loaded normally, but after reseating the connectors on the A drive it now gives me a 'bad sector' error from the same disk instead of a 'boot error' cascade.

Is there anything I can try to fix the A drive before the boss tells me to put the thing back together and sell it as-is?

Stone
October 24th, 2017, 03:19 PM
Have you tried cleaning the heads?

Fire-Flare
October 25th, 2017, 08:43 AM
Have you tried cleaning the heads?

Anything else I can try while I wait for a 5.25" Cleaning kit to arrive?

modem7
October 25th, 2017, 11:45 PM
Anything else I can try while I wait for a 5.25" Cleaning kit to arrive?
Clean then re-lubricate the drive's [rails (http://minuszerodegrees.net/images3/tandon_tm100_rails.jpg)].

Fire-Flare
October 26th, 2017, 08:50 AM
Clean then re-lubricate the drive's [rails (http://minuszerodegrees.net/images3/tandon_tm100_rails.jpg)].

Will WD-40 work, or should I get something more specific?

modem7
October 27th, 2017, 01:45 PM
Will WD-40 work, or should I get something more specific?
Possibly, but I consider it a bad long term solution. The lubricant that I use is silicon grease.

Chuck(G)
October 27th, 2017, 03:01 PM
I use a pure silicone (no petroleum oil) aerosol. The rails really don't need much other than cleaning.

Stone
October 27th, 2017, 03:35 PM
FWIW, I have lots of floppy drives, some I've had and use regularly for around 25 years and some I only use rarely or occasionaly and I have never had to lubricate the rails on any of them -- not even once.

Now, head cleaning... all the time on drives that I regularly use as less than one second of use with a bad disk can completely foul the heads.

modem7
October 27th, 2017, 06:12 PM
FWIW, I have lots of floppy drives, some I've had and use regularly for around 25 years and some I only use rarely or occasionaly and I have never had to lubricate the rails on any of them -- not even once.
I am unaware of anyone saying that this needs to a periodic maintenance activity. The fact is, we have had posts on these forums from people with faulty 5.25" floppy drives, and sometimes, the cause has turned out to be deteriorated lubrication on the rails (because of non-use?). That is the reason for the suggestion.

zombienerd
October 27th, 2017, 06:31 PM
I had a 1.2mb drive that the heads wouldn't move properly until the rails and worm gear were lubricated. I used a WD-40 brand lithium grease in a spray can. It worked wonderfully.

I clean my floppy drive heads with a Q-tip and Isopropyl alcohol. Never had a cleaning kit.

Chuck(G)
October 27th, 2017, 06:48 PM
I bought a bunch of NOS 3.5" drives that wouldn't function correctly. Turned out to be dried-out white grease on the leadscrews. Sometimes you do have to clean the things.

Fire-Flare
October 31st, 2017, 10:54 AM
The cleaning kit arrived and didn't help, nor has a Q-tip with alcohol directly to the head.

I spun the leadscrew by hand and watched it return to its former position when I turned the machine on, so it's probably not a lube issue.

I've attached a picture of the drive's board, perhaps you guys can see a problem that's eluding me?

41676

zombienerd
October 31st, 2017, 11:13 AM
The cleaning kit arrived and didn't help, nor has a Q-tip with alcohol directly to the head.

I spun the leadscrew by hand and watched it return to its former position when I turned the machine on, so it's probably not a lube issue.

I've attached a picture of the drive's board, perhaps you guys can see a problem that's eluding me?

41676

Are those electrolytic capacitors bulging at all? Hard to tell in the pictures.

Fire-Flare
October 31st, 2017, 11:32 AM
Hard to tell here too since they're so small and don't have grooves on the tops to show expansion.

Chuck(G)
October 31st, 2017, 12:08 PM
Got a logic probe or a 'scope?

Fire-Flare
October 31st, 2017, 12:51 PM
Got a logic probe or a 'scope?

We have a few oscilloscopes in the warehouse, and one of my coworkers may have a probe. I've never used either though.

Chuck(G)
October 31st, 2017, 12:53 PM
My approach is when the disk spins and nothing else seems to work is to probe the signals going in and coming out of the drive. Since floppy drives are so simple, many faults show up glaringly.

Fire-Flare
October 31st, 2017, 01:20 PM
Even if that were the case, I wouldn't know where to begin or how to fix it.

It looks to me like the best option is to reassemble the machine and sell it as-is.