Fixing 8" disk hubs

[Steve Thatcher]

Another non-obvious possibility is that the disk jacket itself has been pinched around the edges and the extra friction is keeping the disk from spinning in the jacket. If you need the info off the disk, cut a small margin of the jacket off around the edges or you can remove the internal disk itself and put it in a known good jacket (cut just one end of the jacket for the disk to slide back into the jacket). Experiment...

best regards, Steve Thatcher

-----Original Message-----
>From: Tony Duell <ard at p850ug1.demon.co.uk>
>Sent: Mar 2, 2006 1:31 PM
>To: cctalk at classiccmp.org
>Subject: Re: Fixing 8" disk hubs
>
>> 
>> All:
>> 
>>  
>> 
>>             I'm restoring an IMSAI system which has an Icom "Frugal Floppy"
>> system setup (8" FD-400 drives). I've been getting CRC errors since I got it
>> running a few weeks ago, so I decided to run it with the cover off to try to
>> see what's going on. Tonight I noticed that the floppy disk itself wasn't
>> spinning. The hub engages when the door closes but it must be *just* missing
>> contacting the diskette by *this* much.
>> 
>>  
>> 
>>             What kind of tricks are people using to improve the contact
>> between the floppy disk and the spindle hub? I remember they made "hub
>> protectors" for 5.25" disks - is there something similar? Other ideas?
>
>I think you're going about it in the wrong way. If the disks are not 
>obviously physically damaged (and you don't mention that they are), the 
>drive should grip them. If it doesn't, the fault is with the drive, not 
>with the disks. And I never believe in 'curing the symptoms'
>
>For some reason your drive is not clamping the disk properly. Maybe 
>there's a spring that's not providing enough tension. Maybe a mechanical 
>latch is not alighned properly and the clamp is not held down far enough. 
>I would start looking at something like that.
>
>-tony