Re: 8 inch floppies, decaying

2018-07-13 Thread Chuck Guzis via cctalk
On 07/12/2018 09:05 PM, David C. Jenner via cctech wrote:
> Would Chuck's temperature and Al's oven be appropriate for old magtapes,
> too?

My "cooker" is home-built and heavily insulated.  It has a 75W
incandescent for heat and a low-speed fan for circulation.  I use a PID
controller to keep the temperature within limits. An RTD sensor sits in
the middle of the chamber.

With spacing for air circulation, I can do about 7 tapes at a time.  My
"tape tower" is constructed from a trimmed-down PVC toilet flange
attached to a 3" lchedule 80 PVC pipe.  Spacers are made from 4"
diameter schedule 80 PVC, which fits nicely into the write-enable ring
recess on each reel.

Because of the insulation, it uses very little electricity.  There's a
70C thermal fuse just in case things get out of hand.

--Chuck


Re: 8 inch floppies, decaying

2018-07-12 Thread David C. Jenner via cctalk
Would Chuck's temperature and Al's oven be appropriate for old magtapes, 
too?


On 7/11/18 9:10 AM, Al Kossow via cctech wrote:



On 7/11/18 8:57 AM, Rob Jarratt via cctalk wrote:

Be wary though, domestic ovens apparently fluctuate wildly.


Use a food dehydrator

this is the unit I use for QIC tapes (weston 10 tray stainless steel dehydrator 
model 74-1001-2)

https://www.ebay.com/itm//113143490361

but I do them a couple dozen at at time




Re: 8 inch floppies, decaying

2018-07-12 Thread Liam Proven via cctalk
On Wed, 11 Jul 2018 at 20:05, Fred Cisin via cctalk
 wrote:
>
> Don't use pumice to clean off the pumas.  (they won't like it)
> Stick with well whale oil.

Also great for rosewood, I hear.

-- 
Liam Proven - Profile: https://about.me/liamproven
Email: lpro...@cix.co.uk - Google Mail/Hangouts/Plus: lpro...@gmail.com
Twitter/Facebook/Flickr: lproven - Skype/LinkedIn: liamproven
UK: +44 7939-087884 - ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053


Re: 8 inch floppies, decaying

2018-07-12 Thread Christian Corti via cctalk

On Wed, 11 Jul 2018, Al Kossow wrote:

On 7/11/18 2:21 AM, Christian Corti via cctalk wrote:


I use Screen 99 for cleaning floppies


MSDS
https://store.comet.bg/download-file.php?id=16956
first ingredient listed; isopropyl alcohol


Of course, somehow you need some "magic" in the stuff ;-)
But as you might have seen, the weight in weight is 10% maximum. And when 
sprayed on the surface (only a small spot) it generates a nice solid foam. 
It hasn't dissolved the binder/oxide for now, not even on Wabash floppies 
(that in my experience aren't too horrible, some noname stuff is much 
worse).
If I'm afraid that it might dissolve the media I can always test it 
first on the inner side next to the hub hole. And I don't rub the 
media with high pressure, only gently. It is important to extract the 
floppy from its sleeve for cleaning, though.


Christian


Re: 8 inch floppies, decaying

2018-07-11 Thread dwight via cctalk
I'm the victim of the spell checker. Thanks for the fix.

Dwight



From: cctalk  on behalf of Fred Cisin via cctalk 

Sent: Wednesday, July 11, 2018 11:05:43 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: 8 inch floppies, decaying

On Wed, 11 Jul 2018, dwight via cctalk wrote:
> Next is the smooth orange oil hand cleaner. ( not the stuff with pumas
> ). Really cleans things great and good for killing ants. Again, rinse
> maybe it might need a little detergent and then rinse.

Don't use pumice to clean off the pumas.  (they won't like it)
Stick with well whale oil.


Re: 8 inch floppies, decaying

2018-07-11 Thread Fred Cisin via cctalk

On Wed, 11 Jul 2018, dwight via cctalk wrote:
Next is the smooth orange oil hand cleaner. ( not the stuff with pumas 
). Really cleans things great and good for killing ants. Again, rinse 
maybe it might need a little detergent and then rinse.


Don't use pumice to clean off the pumas.  (they won't like it)
Stick with well whale oil.


Re: 8 inch floppies, decaying

2018-07-11 Thread dwight via cctalk
I forgot one


Butter. Also needs detergent cleaning afterwards.

Dwight





From: cctalk  on behalf of dwight via cctalk 

Sent: Wednesday, July 11, 2018 10:29:41 AM
To: Al Kossow; General Discussion: On-Topic and Off-Topic Posts
Subject: Re: 8 inch floppies, decaying

I don't recall the concentration I used. I would recommend not using it for 
most conditions. I recall that I'd tried various other cleaning methods. I 
recall using water, water/detergent and may have even tried windex(?). None of 
the other things would touch it. The stuff on the surfaces was the adhesive use 
to hold the fiber envelope liners in place. I removed the disk from their 
envelopes and placed the disk on a clean flat plastic surface. I use swabs to 
rub the areas effected ( it looked similar to what we call screen fungus ). I 
went through a lot of swabs and I believe I rinsed them afterwards.

There are a few other cleaning methods that one might try. I've never tried 
these myself

The first might make you cringe a little. That is to use saliva. It is actually 
a type of digesting fluid. Of course, rinse it off when you get the offending 
stuff loose.

Next is the smooth orange oil hand cleaner. ( not the stuff with pumas ). 
Really cleans things great and good for killing ants. Again, rinse maybe it 
might need a little detergent and then rinse.

WIndex, maybe.

GooGone, also a maybe ( I expect it to damage the disk but who knows )

In general I'd go with Chuck's advice. He has done more work with disk and 
tapes than anyone here else except possibly Al.

Dwight




From: cctalk  on behalf of Al Kossow via cctalk 

Sent: Wednesday, July 11, 2018 9:10:14 AM
To: cctalk@classiccmp.org
Subject: Re: 8 inch floppies, decaying



On 7/11/18 8:57 AM, Rob Jarratt via cctalk wrote:
> Be wary though, domestic ovens apparently fluctuate wildly.

Use a food dehydrator

this is the unit I use for QIC tapes (weston 10 tray stainless steel dehydrator 
model 74-1001-2)

https://www.ebay.com/itm//113143490361
[https://i.ebayimg.com/images/i/113143490361-0-1/s-l1000.jpg]<https://www.ebay.com/itm//113143490361>

Weston Commercial Stainless Steel 10 Tray Food Dehydrator 1000W 638029776257 | 
eBay<https://www.ebay.com/itm//113143490361>
www.ebay.com<http://www.ebay.com>
It is 1000 watts. It is in good used condition with no dings and in good 
working condition. Great for jerky, vegetables or fruit. | eBay!



but I do them a couple dozen at at time



Re: 8 inch floppies, decaying

2018-07-11 Thread dwight via cctalk
I don't recall the concentration I used. I would recommend not using it for 
most conditions. I recall that I'd tried various other cleaning methods. I 
recall using water, water/detergent and may have even tried windex(?). None of 
the other things would touch it. The stuff on the surfaces was the adhesive use 
to hold the fiber envelope liners in place. I removed the disk from their 
envelopes and placed the disk on a clean flat plastic surface. I use swabs to 
rub the areas effected ( it looked similar to what we call screen fungus ). I 
went through a lot of swabs and I believe I rinsed them afterwards.

There are a few other cleaning methods that one might try. I've never tried 
these myself

The first might make you cringe a little. That is to use saliva. It is actually 
a type of digesting fluid. Of course, rinse it off when you get the offending 
stuff loose.

Next is the smooth orange oil hand cleaner. ( not the stuff with pumas ). 
Really cleans things great and good for killing ants. Again, rinse maybe it 
might need a little detergent and then rinse.

WIndex, maybe.

GooGone, also a maybe ( I expect it to damage the disk but who knows )

In general I'd go with Chuck's advice. He has done more work with disk and 
tapes than anyone here else except possibly Al.

Dwight




From: cctalk  on behalf of Al Kossow via cctalk 

Sent: Wednesday, July 11, 2018 9:10:14 AM
To: cctalk@classiccmp.org
Subject: Re: 8 inch floppies, decaying



On 7/11/18 8:57 AM, Rob Jarratt via cctalk wrote:
> Be wary though, domestic ovens apparently fluctuate wildly.

Use a food dehydrator

this is the unit I use for QIC tapes (weston 10 tray stainless steel dehydrator 
model 74-1001-2)

https://www.ebay.com/itm//113143490361
[https://i.ebayimg.com/images/i/113143490361-0-1/s-l1000.jpg]<https://www.ebay.com/itm//113143490361>

Weston Commercial Stainless Steel 10 Tray Food Dehydrator 1000W 638029776257 | 
eBay<https://www.ebay.com/itm//113143490361>
www.ebay.com
It is 1000 watts. It is in good used condition with no dings and in good 
working condition. Great for jerky, vegetables or fruit. | eBay!



but I do them a couple dozen at at time



Re: 8 inch floppies, decaying

2018-07-11 Thread Al Kossow via cctalk



On 7/11/18 8:57 AM, Rob Jarratt via cctalk wrote:
> Be wary though, domestic ovens apparently fluctuate wildly.

Use a food dehydrator

this is the unit I use for QIC tapes (weston 10 tray stainless steel dehydrator 
model 74-1001-2)

https://www.ebay.com/itm//113143490361

but I do them a couple dozen at at time



RE: 8 inch floppies, decaying

2018-07-11 Thread Rob Jarratt via cctalk
Be wary though, domestic ovens apparently fluctuate wildly. I did have success 
with some TK50s in our fan oven set at 40C

Sent from my Windows 10 phone

From: Chuck Guzis via cctalk
Sent: 11 July 2018 16:31
To: Adrian Graham via cctalk
Subject: Re: 8 inch floppies, decaying

On 07/11/2018 02:53 AM, Adrian Graham via cctalk wrote:

> What temperature oven?

58C +/- 0.5C

--Chuck



Re: 8 inch floppies, decaying

2018-07-11 Thread Al Kossow via cctalk



On 7/11/18 8:20 AM, Al Kossow via cctalk wrote:
> 
> 
> On 7/11/18 2:21 AM, Christian Corti via cctalk wrote:
> 
>> I use Screen 99 for cleaning floppies
> 
> MSDS
> 
> https://store.comet.bg/download-file.php?id=16956
> 
> first ingredient listed; isopropyl alcohol
> 
> 


Since I haven't mentioned it for a while, I had the best results with the old 
"Weber Costello Markerboard Cleaner",

(Octylphenoxy Polyethoxyethanol (Triton X-100) and Trisodium Phosphate) which 
is photoflow and a surficant.

then they changed the formula to make it 'green' :-(

Bought a few ingredients (Triton X-100 and Ethylene Glycol) but haven't tried 
making anything.

What you want is a lubricant and a cleaning agent that will take off any gunk 
on the surface without softening the binder.






Re: 8 inch floppies, decaying

2018-07-11 Thread Chuck Guzis via cctalk
On 07/11/2018 02:53 AM, Adrian Graham via cctalk wrote:

> What temperature oven?

58C +/- 0.5C

--Chuck


Re: 8 inch floppies, decaying

2018-07-11 Thread Al Kossow via cctalk



On 7/11/18 2:21 AM, Christian Corti via cctalk wrote:

> I use Screen 99 for cleaning floppies

MSDS

https://store.comet.bg/download-file.php?id=16956

first ingredient listed; isopropyl alcohol




Re: 8 inch floppies, decaying

2018-07-11 Thread Adrian Graham via cctalk


> On 11 Jul 2018, at 03:15, Chuck Guzis via cctalk  
> wrote:
> 
> No, no, no! Do not use isopropanol to clean floppies--you'll wind up
> with a soft oxide coating and a brown rag.  Were these mine, I'd first
> remove them from their jackets and then bake them and then clean them
> with distilled water and perhaps a couple of drops of a wetting agent
> (Kodak Photo-flo is a good) choice--a couple of drops goes a long way).
> 
> You should be good to go--at least my experience tells me that.


Hi Chuck,

What temperature oven?

Cheers,

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk





Re: 8 inch floppies, decaying

2018-07-11 Thread Adrian Graham via cctalk


> On 11 Jul 2018, at 09:33, Terry Stewart via cctalk  
> wrote:
> 
> Just my experience,  I once did a trial where I took two identical 5,25
> inch disks of the same batch from the same manufacturer.  These were clean
> disks which both formatted and verified just fine, but I wanted to see if
> IPA did indeed damage the disk.
> 
> One I swabbed one with 75% IPA, the other with warm water with a touch of
> dishwashing liquid.
> 
> On checking the IPA swabbed disk now showed a few damaged sectors.  The
> water/detergent one did not.
> 
> It's not scientific (just one rep) and I was quite aggressive with the
> wiping.  However, it made me steer away from IPA.  Immersing the platters
> in warm water with a touch of detergent, and gently wiping (then air
> drying) works well for me when cleaning "dirty disks".
> 
> Terry (Tez)
> 
> On Wed, Jul 11, 2018 at 8:17 PM, Steve Malikoff via cctalk <
> cctalk@classiccmp.org> wrote:


Thanks everyone!

I found another box so I’ve got 20 ‘new’ ones now. I’ll try all of the above 
methods and see where it gets me. Pity I don’t have any spare jackets but my 
plan was to attempt to get the CPT to boot and since the original boot disk has 
damaged sectors 0-3 and the previous owner didn’t make a copy I’m a bit stuck 
anyway.

It was good to be able to see actual documents on the data disks with ANADISK 
though, cheers Chuck :)

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk





Re: 8 inch floppies, decaying

2018-07-11 Thread Christian Corti via cctalk

On Wed, 11 Jul 2018, dwight wrote:
I've had the goo from the adhesive of 5.25 inch 360k disk come through 
the nice liner and make gobs on the disk. I tried several thing but 
found that isopropanol worked without removing any of the magnetic 
material ( maybe s tiny amount that was likely loose already ). I'm not 
saying it would be the same for 8 inch disk. Once working I did copy 
them to floppies without liners.


I use Screen 99 for cleaning floppies, and that has proved to be the best 
so far, giving a clean and smooth surface. There's no need to grapple with 
several different fluids. I don't even use lint-free cloths and the like, 
I use paper towels. The surface is so smooth that all the remaining dust 
can be blown away easily.


Christian


Re: 8 inch floppies, decaying

2018-07-11 Thread Terry Stewart via cctalk
Just my experience,  I once did a trial where I took two identical 5,25
inch disks of the same batch from the same manufacturer.  These were clean
disks which both formatted and verified just fine, but I wanted to see if
IPA did indeed damage the disk.

One I swabbed one with 75% IPA, the other with warm water with a touch of
dishwashing liquid.

On checking the IPA swabbed disk now showed a few damaged sectors.  The
water/detergent one did not.

It's not scientific (just one rep) and I was quite aggressive with the
wiping.  However, it made me steer away from IPA.  Immersing the platters
in warm water with a touch of detergent, and gently wiping (then air
drying) works well for me when cleaning "dirty disks".

Terry (Tez)

On Wed, Jul 11, 2018 at 8:17 PM, Steve Malikoff via cctalk <
cctalk@classiccmp.org> wrote:

> Fred asked
> > What concentration of IPA were you using?
>
> 99% Laboratory grade. Not very pleasant to have on the skin, it dries it
> out shockingly.
>
> > There might be a difference in results between 70% and 91%
> >
> > There might also even be a difference in the oxide formulation between
> > brands.  (If Chuck was trying to clean a Wabash, then it might dissolve
> > right through the plastic.)
>
> I've had Computer Resources, Wabash and other cheap diskettes long ago,
> they were
> none too good. Verbatim and Dysan always seemed pretty reliable for me.
>
>


Re: 8 inch floppies, decaying

2018-07-11 Thread Steve Malikoff via cctalk
Fred asked
> What concentration of IPA were you using?

99% Laboratory grade. Not very pleasant to have on the skin, it dries it out 
shockingly.

> There might be a difference in results between 70% and 91%
>
> There might also even be a difference in the oxide formulation between
> brands.  (If Chuck was trying to clean a Wabash, then it might dissolve
> right through the plastic.)

I've had Computer Resources, Wabash and other cheap diskettes long ago, they 
were
none too good. Verbatim and Dysan always seemed pretty reliable for me.



Re: 8 inch floppies, decaying

2018-07-11 Thread Chuck Guzis via cctalk
On 07/10/2018 09:14 PM, Steve Malikoff via cctalk wrote:

> So there you have it. I'm not asserting that all diskettes were manufactured 
> as well as this IBM one but I stand by
> what I suggested, I would certainly try IPA again if I had to. By the 1970s I 
> would think a diskette surface had come a
> long way from my dad's RAMAC days and even the 1/2" magnetic tape from the 
> 50s and 60s, where I would be considerably
> more reticent trying this.

Well, they're your disks.   I've seen a system for reading magnetic tape
where a continuous bath was used to combad sticky-shed, but there were
no comments on the condition of the medium after reading.

If these were my disks, I wipe them down with cyclomethicone.  That
would at least lubricate them and leave them (after evaporation) in
pretty much the same state as you started.

Remember that a fatty acid usually was used as a medium lubricant when
these disks were manufactured.  The last thing in the world you want to
do is dissolve this and remove it.

But, as I remarked, they're your disks.  I've certainly seen my share of
8" CPT floppies--and 1960s 1/2" tape.

--Chuck


Re: 8 inch floppies, decaying

2018-07-10 Thread Fred Cisin via cctalk

No, no, no! Do not use isopropanol to clean floppies--you'll wind up


On Wed, 11 Jul 2018, Steve Malikoff via cctalk wrote:

Well, I suggested IPA (to Chuck's horror) so decided to put my money where my 
mouth is and try it myself.
Using a 38-year old 8" IBM Diskette 1 (128-bit sectors) that I had lying around 
(it's physically damaged) I proceeded
to clean it with high-grade IPA and a cotton bud as I suggested.


What concentration of IPA were you using?

There might be a difference in results between 70% and 91%

There might also even be a difference in the oxide formulation between 
brands.  (If Chuck was trying to clean a Wabash, then it might dissolve 
right through the plastic.)



I've used water, and a heavily diluted dish soap.
And Kodak "Photo-Flow"
I kept a few spare jackets on hand.
I had cotton film editing gloves around, but didn't always bother to use 
them.
I was going to modify some 5x7 and 8x10 film hangers to use a film washer, 
but never got around to needing it.



I often received 5.25" and 8" diskettes that didn't turn freely in the 
jacket.
Most of the time, rubbing each of the four edges HARD against the 
corner of the table would loosen them up.  If not, I just slit the jacket, 
and put them into a spare jacket.


--
Grumpy Ol' Fred ci...@xenosoft.com


Re: 8 inch floppies, decaying

2018-07-10 Thread Steve Malikoff via cctalk
Chuck reckoned
> No, no, no! Do not use isopropanol to clean floppies--you'll wind up
> with a soft oxide coating and a brown rag.  Were these mine, I'd first
> remove them from their jackets and then bake them and then clean them
> with distilled water and perhaps a couple of drops of a wetting agent
> (Kodak Photo-flo is a good) choice--a couple of drops goes a long way).
>
> You should be good to go--at least my experience tells me that.


Well, I suggested IPA (to Chuck's horror) so decided to put my money where my 
mouth is and try it myself.

Using a 38-year old 8" IBM Diskette 1 (128-bit sectors) that I had lying around 
(it's physically damaged) I proceeded
to clean it with high-grade IPA and a cotton bud as I suggested.

After a good scrubbing, no detectable oxide came off at all. It even looked a 
tiny bit cleaner on the area I tried.
Photos:

Diskette:  http://www.surfacezero.com/g503/data/500/diskette_1.jpg

Before:http://www.surfacezero.com/g503/data/500/diskette_before.jpg

After: http://www.surfacezero.com/g503/data/500/diskette_after.jpg

So there you have it. I'm not asserting that all diskettes were manufactured as 
well as this IBM one but I stand by
what I suggested, I would certainly try IPA again if I had to. By the 1970s I 
would think a diskette surface had come a
long way from my dad's RAMAC days and even the 1/2" magnetic tape from the 50s 
and 60s, where I would be considerably
more reticent trying this.

Steve.



Re: 8 inch floppies, decaying

2018-07-10 Thread dwight via cctalk
I've had the goo from the adhesive of 5.25 inch 360k disk come through the nice 
liner and make gobs on the disk. I tried several thing but found that 
isopropanol worked without removing any of the magnetic material ( maybe s tiny 
amount that was likely loose already ). I'm not saying it would be the same for 
8 inch disk. Once working I did copy them to floppies without liners.

Dwight



From: cctalk  on behalf of Chuck Guzis via 
cctalk 
Sent: Tuesday, July 10, 2018 7:15:13 PM
To: Richard Pope via cctalk
Subject: Re: 8 inch floppies, decaying

No, no, no! Do not use isopropanol to clean floppies--you'll wind up
with a soft oxide coating and a brown rag.  Were these mine, I'd first
remove them from their jackets and then bake them and then clean them
with distilled water and perhaps a couple of drops of a wetting agent
(Kodak Photo-flo is a good) choice--a couple of drops goes a long way).

You should be good to go--at least my experience tells me that.

--Chuck




Re: 8 inch floppies, decaying

2018-07-10 Thread Chuck Guzis via cctalk
No, no, no! Do not use isopropanol to clean floppies--you'll wind up
with a soft oxide coating and a brown rag.  Were these mine, I'd first
remove them from their jackets and then bake them and then clean them
with distilled water and perhaps a couple of drops of a wetting agent
(Kodak Photo-flo is a good) choice--a couple of drops goes a long way).

You should be good to go--at least my experience tells me that.

--Chuck




Re: 8 inch floppies, decaying

2018-07-10 Thread Richard Pope via cctalk

Steve, Adrian,
I am pretty certain that alcohol will break down the binders and 
remove the oxide.  Since the bad disc was run through the drive the 
head/heads should be cleaned before any more read or write attempts are 
made otherwise more discs will be damaged.

Thanks,
rich!

On 7/10/2018 8:25 PM, Steve Malikoff via cctalk wrote:

Adrian said:

Tonight I got my imaging PC to successfully read some of the 8” disks from my 
CPT8500 word processor using one of its own Tandon TM848-01 drives, sadly it 
seems the boot disk is toast but I’ve been able to dump some of the data disks 
as well as the Utilities. Since I have a box of unused disks

I thought I’d try writing back an image but got a lot of CRC errors. Closer inspection 
of the disk itself shows this - 
http://www.binarydinosaurs.co.uk/8inchFloppyImaging-7.jpg 
 - which looks like 
damp.>

Is it actually the magnetic coating breaking down? Dare I attempt cleaning?


If it was me I certainly would attempt cleaning, after all it was unreadable 
anyway. Perhaps try cleaning a test area with a cotton bud (Q-tip)
and isopropyl alcohol. If the stuff comes off without oxide removal then I'd 
slice the top edge off the jacket to remove (with clean disposable
gloves on a lint-free surface) and clean the whole disc and finally put into a 
clean jacket.

Steve.






Re: 8 inch floppies, decaying

2018-07-10 Thread Steve Malikoff via cctalk
Adrian said:
> Tonight I got my imaging PC to successfully read some of the 8” disks from my 
> CPT8500 word processor using one of its own Tandon TM848-01 drives, sadly it 
> seems the boot disk is toast but I’ve been able to dump some of the data 
> disks as well as the Utilities. Since I have a box of unused disks
I thought I’d try writing back an image but got a lot of CRC errors. Closer 
inspection of the disk itself shows this - 
http://www.binarydinosaurs.co.uk/8inchFloppyImaging-7.jpg 
 - which looks like 
damp.>
> Is it actually the magnetic coating breaking down? Dare I attempt cleaning?


If it was me I certainly would attempt cleaning, after all it was unreadable 
anyway. Perhaps try cleaning a test area with a cotton bud (Q-tip)
and isopropyl alcohol. If the stuff comes off without oxide removal then I'd 
slice the top edge off the jacket to remove (with clean disposable
gloves on a lint-free surface) and clean the whole disc and finally put into a 
clean jacket.

Steve.



8 inch floppies, decaying

2018-07-10 Thread Adrian Graham via cctalk
Hi folks,

Tonight I got my imaging PC to successfully read some of the 8” disks from my 
CPT8500 word processor using one of its own Tandon TM848-01 drives, sadly it 
seems the boot disk is toast but I’ve been able to dump some of the data disks 
as well as the Utilities. Since I have a box of unused disks I thought I’d try 
writing back an image but got a lot of CRC errors. Closer inspection of the 
disk itself shows this - 
http://www.binarydinosaurs.co.uk/8inchFloppyImaging-7.jpg 
 - which looks like 
damp.

Is it actually the magnetic coating breaking down? Dare I attempt cleaning?

Just for another test I tried reading some of my DEC diagnostic floppies since 
I hoped they were RX01 format, but they error constantly so they must be RX02s.

Still, it was good to see the drive spring into life :)

-- 
adrian/witchy
Owner of Binary Dinosaurs, the UK's biggest home computer collection?
t: @binarydinosaursf: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk