1 Mar
2006
1 Mar
'06
6:59 p.m.
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?
As always, thanks.
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: <http://highgate.comm.sfu.ca/~rcini/classiccmp/>
http://highgate.comm.sfu.ca/~rcini/classiccmp/
/************************************************************/
1 Mar
1 Mar
7:07 p.m.
On Wed, 1 Mar 2006, Richard A. Cini wrote:
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?
Yes, there were hub protectors for 8" diskettes.
I sold a bunch of Inmac ones at VCF a few years ago.
Howzbout: take a dead 8" diskette, cut out the center, and cement it to
the spindle hub, to extend it slightly?
7:15 p.m.
I was looking for hub protectors using Google and coming up with nada. My
daughter uses this adhesive-backed high-density foam that's about 1/16"
thick for various craft projects. I was going to try that before you IDed
the diskette idea.
I pressed down on the top hub while the spindle was spinning and the gap is
somewhere between 1/32" and 1/16". How much slippage is necessary on the
hub?
-----Original Message-----
From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org]
On Behalf Of Fred Cisin
Sent: Wednesday, March 01, 2006 10:07 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Fixing 8" disk hubs
On Wed, 1 Mar 2006, Richard A. Cini wrote:
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?
Yes, there were hub protectors for 8" diskettes.
I sold a bunch of Inmac ones at VCF a few years ago.
Howzbout: take a dead 8" diskette, cut out the center, and cement it to
the spindle hub, to extend it slightly?
2 Mar
2 Mar
5:21 p.m.
I have a stash of about 200 disks from this particular haul. The disk in
this case is a blank one (as I'm trying to run controller diagnostics) and
it appears to move freely. The spindle top is spring loaded so I'll check
that out first.
Thanks.
-----Original Message-----
From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org]
On Behalf Of Fred Cisin
Sent: Wednesday, March 01, 2006 10:07 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Fixing 8" disk hubs
On Wed, 1 Mar 2006, Richard A. Cini wrote:
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?
Yes, there were hub protectors for 8" diskettes.
I sold a bunch of Inmac ones at VCF a few years ago.
Howzbout: take a dead 8" diskette, cut out the center, and cement it to
the spindle hub, to extend it slightly?
7:13 p.m.
I played around with the drive a bit tonight and it seems that the metal
bracket that lifts the head pad when the head unloads (the one that sits
opposite the head on a single-sided drive) was interfering with the hub a
bit. Bending the bracket slightly fixed the problem with the disk contact.
It also fixed another problem where if the drive door was snapped open, the
head pad arm would come off of this bracket.
-----Original Message-----
From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org]
On Behalf Of Fred Cisin
Sent: Wednesday, March 01, 2006 10:07 PM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Fixing 8" disk hubs
On Wed, 1 Mar 2006, Richard A. Cini wrote:
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?
Yes, there were hub protectors for 8" diskettes.
I sold a bunch of Inmac ones at VCF a few years ago.
Howzbout: take a dead 8" diskette, cut out the center, and cement it to
the spindle hub, to extend it slightly?
1 Mar
1 Mar
7:21 p.m.
On 3/1/2006 at 9:59 PM Richard A. Cini wrote:
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 don't know what hub clamping method the drive uses, but it might be worth
looking to see if there's a spring as part of the clamping mechanism that's
been weakened. Rather than fool with diskettes with data on them, I'd try
to find the reason that the drive isn't clamping them.
Cheers,
Chuck
2 Mar
2 Mar
10:31 a.m.
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
11:06 a.m.
Stupid question.... Is the Diskette still good ?
Do the disks still spin fee in their jackets?
Or do they have stiction ?
I had that problem long ago and ended up cutting the disk out of the bad disk jacket and
putting it in a good diskette jacket.
It spun up, I got my data off and trash both diskettes.
Something got inside the diskette or just died in there that made it stick.
An slit down the side worked well, to get my data out intact.
I recovered a floppy that had been bent and was binding that way too.
I both cases they did not spin correctly in an otherwise good drive.
8"floppies were not designed as long life, long term storage. :)
BTW I had a drive do that and swapping the upper hub and spring fixed it.
On close inspection the plastic cone side of the hub was cracked and did not transfer the
force to the rim of the disk.
Just my thoughts
Good luck...
Bob Bradlee
6653
days inactive
6653
days old
7 comments
5 participants
participants (5)
-
ard＠p850ug1.demon.co.uk -
Bob＠BRADLEE.ORG -
cclist＠sydex.com -
cisin＠xenosoft.com -
rcini＠optonline.net