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Druid6900
February 4th, 2017, 03:56 PM
I have about 3 hard drives that I can get to spin up, but, if left off overnight, they won't spin up again.

I've read a lot of stuff on here, pro and con, but nothing definitive...

Now, does it work and, if so, is it a data recovery one shot or will the drive continue to operate?

mbbrutman
February 4th, 2017, 04:05 PM
I've heard of people baking tapes to stabilize them, but not entire hard drives.

I wouldn't do it. Heat is generally the enemy of anything. You're going to heat up the chips, the circuit board, the ribbon connectors, the flex connector that connects to the heads, etc.

I would run a disk exerciser on the drives; get the heads moving around so that the lubricant that is binding them will be more evenly spread about. You don't want to do a hard-core seek test the drives because that can heat up the voice coil if the drives use that. But getting some movement around the drive will help redistribute the lubricant.

Lastly, if these drives need to be explicitly parked make sure you are doing so. The landing zone area is textured differently to avoid stiction, but that might not be working correctly anymore if there has been an excessive amount of lubricant landing in those areas. Also, if the power supply is not strong enough the drives might have problems spinning up; ensure you have a good power supply.

SomeGuy
February 4th, 2017, 04:54 PM
All heating up a hard drive will do is loosen up lubricant on the motor spindle. It is more or less a one shot deal. Once the drive cools and sits for a while the lubricant will just harden up again.

ardent-blue
February 5th, 2017, 04:07 AM
Some old IBM drives were known for stiction. A German tech would place a balky drive in his back window, go shopping, and then take the drive, give it a few sharp turns, and try it. But it is a good idea to quickly back the drive up once it is free....

:confuseddevil:

Druid6900
February 5th, 2017, 05:54 AM
OK, so, the general consensus is no.

I'll try Mr Brutman's suggest and run it through a few days of on again/off again drive seeks/random reads/sequential reads and see what happens.

I plugged the drive directly into a 250 PSU after taking it off the card and it wouldn't spin it up either. If I give it a crack on the edge against the workbench, it will spin up and operate fine until I leave it off overnight again.

I'll post the results of the test drive in a few days.....

Chuck(G)
February 5th, 2017, 07:16 AM
I'll demur a bit on this one...

If you've got the data off the drive, what do you have to lose? It's not as if stiction is going to go away on its own.

Baking usually involves moderate temperatures (58C typically) for several hours to several days While this is above the rated working temperature of many electronic components, you're probably okay in baking the hda itself. I suspect that most of the drive is rated for at least 85C, non-operating. This may cause some organic polymers (i.e. rubber and plastics) to outgas, but even that's likely to be minor.

If you've got a temperature-controlled oven and can safely remove the PCB and can risk losing the drive, I say, why not go for it?

mbbrutman
February 5th, 2017, 08:04 AM
I used to work for a major hard drive manufacturer.

85 Celsius is 185 Fahrenheit. The idea of baking an entire hard drive at these temperatures is horrifying to me.

Druid6900
February 5th, 2017, 08:14 AM
I'll demur a bit on this one...

If you've got the data off the drive, what do you have to lose? It's not as if stiction is going to go away on its own.

Baking usually involves moderate temperatures (58C typically) for several hours to several days While this is above the rated working temperature of many electronic components, you're probably okay in baking the hda itself. I suspect that most of the drive is rated for at least 85C, non-operating. This may cause some organic polymers (i.e. rubber and plastics) to outgas, but even that's likely to be minor.

If you've got a temperature-controlled oven and can safely remove the PCB and can risk losing the drive, I say, why not go for it?

That's basically, what I was thinking, Chuck. It's either that or toss the drives. They are no good as they are, so, thinning out the spindle lubricant with heat is going to lose me nothing.

I have an oven that can get down to 70C and I can strip it down to the bubble, so, how long do you figure until it's "done"?

Mike, try not to think about it, it'll only upset you....

NeXT
February 5th, 2017, 08:28 AM
I don't trust baking methods in conventional ovens. While it might be able to drop down to 70c its thermal regulation will be extremely poor.
I'd suggest the same device used for tape baking which is essentially a food dehydrator. Set the temperature to 70c, pop it in on Monday and come back on Friday.

Stone
February 5th, 2017, 08:32 AM
HEHEEHHEHEHEEHEHHEHEEHEHEHEHEHEHE...

Just get a box of brownies, follow the instructions and when they're done enjoy the SuperBowl!!!!! :-)

mbbrutman
February 5th, 2017, 09:18 AM
It's an experiment ... you can do what you want with what are effectively disposable hard drives.

However, I don't even understand the basis of the experiment. Baking tape media is a known trick. Hard drive platters are not anywhere near the same as tape media. I would not assume that they'll behave in a similar manner.

I'm particularly worried about anything that might affect the plastics or flexible components of the drive. These components have aged; what might have been tolerable for them 20 years ago might be harmful to them now.

Running the drives will heat them up, presumably to within their operating ranges. If you do a prolonged exercising on them make sure they have some cooling; running open on a desk is not enough, they are designed to be in a case or enclosure with some air flow. And avoid anything that looks like a seek test; you want some movement, not to heat the voice coils up too much.

(We've had pretty high quality hard drives destroyed by people running seek benchmarks on them. Good hard drives will protect themselves against that kind of thing by rate limiting seeking behavior.)

MikeS
February 5th, 2017, 09:18 AM
That's basically, what I was thinking, Chuck. It's either that or toss the drives. They are no good as they are, so, thinning out the spindle lubricant with heat is going to lose me nothing.
It's often not so much an issue of the spindle lubricant as it is one or more heads actually sticking to the platter, sometimes so hard that manually turning the shaft actually rips the head off its support.

Running the drive for a time has never done anything for me; back in the day I had clients running 24/7 with no problems until there was a power failure or shutdown for some reason, when the drives (all Seagate as it happens) would have to be 'unstuck' manually.

But nothing to lose; I'd remove the PCB, puddle some oil on the bearing and let it cook for a while; maybe even open it up and see whether it's the bearing or the actual heads.

But in any case I doubt that the drive would ever be reliable.

Good luck!

Stone
February 5th, 2017, 09:34 AM
It's often not so much an issue of the spindle lubricant as it is one or more heads actually sticking to the platter, sometimes so hard that manually turning the shaft actually rips the head off its support.Exactly... and since there are multiple types of stiction there is certainly no 'one fix for all' solution. Applying the 'wrong' fix can possible worsen the situation instead of lessening or repairing the problem. Shooting from the hip has it's own inherent dangers.

Chuck(G)
February 5th, 2017, 09:50 AM
That's basically, what I was thinking, Chuck. It's either that or toss the drives. They are no good as they are, so, thinning out the spindle lubricant with heat is going to lose me nothing.

I have an oven that can get down to 70C and I can strip it down to the bubble, so, how long do you figure until it's "done"?

Mike, try not to think about it, it'll only upset you....

Mike--I didn't say 85C, I said 58C, which is 136F. I mentioned that the electronic components are probably rated to 85C (most capacitors are)--I don't recommend baking at that temperature. But a lot of warehouses in Texas and Arizona get that warm during the summertime (cf. stories about Tandy's operation in Fort Worth indicate temps much higher than that).

FWIW, I use a temperature-controlled (PID) oven--it's good for +/- 0.5C--it typically takes about 45 minutes to reach the baking temperature, so no thermal shock. The heating element is a 70 watt incandescent bulb.

Bottom line, is that there's nothing to lose if the data's been rescued. I'd rather just toss the drive rather than futz with it, however.

paul
February 5th, 2017, 10:34 AM
I've used a hot water bottle several times to free up stuck heads and it's always been successful.

On the AT, rather than remove the Seagate ST-4096, I placed it under the chassis for 2 hours, refreshed with hot water each hour, a towel over everything to keep the heat in. The other drive that causes issues was a Micropolis 2GB 3.5" in my HP Apollo, which I can remove easily and place directly on the hot water bottle.

I used to use the "shake it all about" method but felt that was abusive to the head's suspension. If I used these machines more than just every six months this probably wouldn't be an issue.

mbbrutman
February 5th, 2017, 10:43 AM
Fair enough - you did say 58C for baking temperature, not 85C.

The basic objection remains the same - heat is the enemy. And disk drive platters are not tape media. I can't see how this is going to be a good idea, but it's not my drive to worry about. If the data is already off of it then it is just an experiment at this point.

Al Kossow
February 5th, 2017, 10:53 AM
The basic objection remains the same - heat is the enemy. And disk drive platters are not tape media. I can't see how this is going to be a good idea

The only thing I can think of is it may create a temperature expansion differential between the head and platter.

I tried this on a couple of drives, and I was able to free a head on one of them.

Humidity apparently is also a problem. I had a drive which at some point had condensation INSIDE the HDA and it has
two heads glued to the plated media.
35936

Chuck(G)
February 5th, 2017, 10:58 AM
Typically what was the maximum non-operating temperature? Well, bitsavers has it as -40C to 60C non-operating for an ST506.

My guess is that 58C is likely to do little, but you never know.

mbbrutman
February 5th, 2017, 10:59 AM
You do bring up a good point - moisture. Driving excess moisture out can be a good thing, and that is something a prolonged baking would do.

Modern drives can deal with differential expansion between the components ... the heads can be raised and lowered a small degree and the servo subsystem can deal with minor movements pretty easily. But this is under normal operating conditions.

I'm not sure how older drives handle differential expansion. The servo system should be fine, and the heads might not even care because the manufacturing tolerances might not have been very tight to begin with.


Druid: Exactly what kind of drives are these anyway?

Druid6900
February 6th, 2017, 07:01 AM
It's an experiment ... you can do what you want with what are effectively disposable hard drives.

However, I don't even understand the basis of the experiment. Baking tape media is a known trick. Hard drive platters are not anywhere near the same as tape media. I would not assume that they'll behave in a similar manner.

I'm particularly worried about anything that might affect the plastics or flexible components of the drive. These components have aged; what might have been tolerable for them 20 years ago might be harmful to them now.

Running the drives will heat them up, presumably to within their operating ranges. If you do a prolonged exercising on them make sure they have some cooling; running open on a desk is not enough, they are designed to be in a case or enclosure with some air flow. And avoid anything that looks like a seek test; you want some movement, not to heat the voice coils up too much.

(We've had pretty high quality hard drives destroyed by people running seek benchmarks on them. Good hard drives will protect themselves against that kind of thing by rate limiting seeking behavior.)

I certainly understand your concern, Mike, and I have run them for 3 days straight, turn them off overnight and, next morning, they don't spin up.

I don't want to recover data from them, I want to extend the working life, even if it's only for a few years.

OK, no seek tests. How about straight sequential R/W tests?

Druid6900
February 6th, 2017, 07:08 AM
It's often not so much an issue of the spindle lubricant as it is one or more heads actually sticking to the platter, sometimes so hard that manually turning the shaft actually rips the head off its support.

Running the drive for a time has never done anything for me; back in the day I had clients running 24/7 with no problems until there was a power failure or shutdown for some reason, when the drives (all Seagate as it happens) would have to be 'unstuck' manually.

But nothing to lose; I'd remove the PCB, puddle some oil on the bearing and let it cook for a while; maybe even open it up and see whether it's the bearing or the actual heads.

But in any case I doubt that the drive would ever be reliable.

Good luck!

On the one, the ST157R, a client's unit (hardcard in a Tandy 1000TX), after getting it spinning, I was able to fdisk, format and install 3.2 and it worked fine, as long as it was left running. Turn it off for more than 6 hours and no spin up. If I turned it off for , oh, 15 minutes and turned it back on, it spun up. I have another unit a Amiga 2000 hard card, some situation.

Druid6900
February 6th, 2017, 07:12 AM
Mike--I didn't say 85C, I said 58C, which is 136F. I mentioned that the electronic components are probably rated to 85C (most capacitors are)--I don't recommend baking at that temperature. But a lot of warehouses in Texas and Arizona get that warm during the summertime (cf. stories about Tandy's operation in Fort Worth indicate temps much higher than that).

FWIW, I use a temperature-controlled (PID) oven--it's good for +/- 0.5C--it typically takes about 45 minutes to reach the baking temperature, so no thermal shock. The heating element is a 70 watt incandescent bulb.

Bottom line, is that there's nothing to lose if the data's been rescued. I'd rather just toss the drive rather than futz with it, however.

I would too, but, these drives cost between $230 and $400 USD on EBay and worse at some sites. I could install a XT-IDE and a CF card configured as a HD, and I might end up doing that if none of this works.

Druid6900
February 6th, 2017, 07:18 AM
You do bring up a good point - moisture. Driving excess moisture out can be a good thing, and that is something a prolonged baking would do.

Modern drives can deal with differential expansion between the components ... the heads can be raised and lowered a small degree and the servo subsystem can deal with minor movements pretty easily. But this is under normal operating conditions.

I'm not sure how older drives handle differential expansion. The servo system should be fine, and the heads might not even care because the manufacturing tolerances might not have been very tight to begin with.


Druid: Exactly what kind of drives are these anyway?

Mike, one is a ST-157R, one is a NEC D3761 and the last is a Conner CP30170E. The first is on a clients Tandy 1000TX hard card and the last is on a clients Amiga 2000 hard card. All are 3.5 inchers.

Stone
February 6th, 2017, 08:14 AM
... I have run them for 3 days straight, turn them off overnight and, next morning, they don't spin up.

I don't want to recover data from them, I want to extend the working life, even if it's only for a few years.I don't think years is possible. I don't think even months is a probability. I would put it in the realm of hours or maybe a few days at best.

Dwight Elvey
February 6th, 2017, 09:02 AM
Sounds like you need to preheat your drive, just like diesel glow plugs.
Add some heaters.
I'm a little like that myself.
Dwight

mbbrutman
February 6th, 2017, 10:34 AM
Seeks are fine, and you need them to spread the lubricant out. Just don't run what is exclusively a seek benchmark ... those can cause damage. Especially full-power side-to-side seeks as opposed to smaller seeks.

The Seagate ST-157R is a stepper motor drive, so it's seek behavior is different than that of a voice coil drive. That one is so primitive you might as well open it up and spray 10W30 motor oil all over. (Just kidding.)

I'll bet that the Connor drive is a voice coil drive based on the shape of it. I don't know what the NEC drive is, but it's a large enough capacity where it might be a voice coil drive too.

offensive_Jerk
February 6th, 2017, 11:56 AM
Seeks are fine, and you need them to spread the lubricant out. Just don't run what is exclusively a seek benchmark ... those can cause damage. Especially full-power side-to-side seeks as opposed to smaller seeks.

The Seagate ST-157R is a stepper motor drive, so it's seek behavior is different than that of a voice coil drive. That one is so primitive you might as well open it up and spray 10W30 motor oil all over. (Just kidding.)

I'll bet that the Connor drive is a voice coil drive based on the shape of it. I don't know what the NEC drive is, but it's a large enough capacity where it might be a voice coil drive too.

So seek tests are only harmful to voice coil drives. When running a benchmark on older full height Seagates, I would wonder if that would do anything bad, since it would shake the whole table, lol.

mbbrutman
February 6th, 2017, 12:06 PM
So seek tests are only harmful to voice coil drives.

Not quite what I said. I said that extended seek tests can be harmful to voice coil drives, especially if the firmware does not do anything to throttle/protect the voice coil from damage. They can overheat if they are used aggressively, like a benchmark might do.

I have no idea how a stepper motor drive would feel about such a test, but I wouldn't do it for the same reasons. A quick few seconds to measure performance, sure ... but not minutes. Not for any type of drive.

Druid6900
February 7th, 2017, 05:57 AM
Seeks are fine, and you need them to spread the lubricant out. Just don't run what is exclusively a seek benchmark ... those can cause damage. Especially full-power side-to-side seeks as opposed to smaller seeks.

The Seagate ST-157R is a stepper motor drive, so it's seek behavior is different than that of a voice coil drive. That one is so primitive you might as well open it up and spray 10W30 motor oil all over. (Just kidding.)

I'll bet that the Connor drive is a voice coil drive based on the shape of it. I don't know what the NEC drive is, but it's a large enough capacity where it might be a voice coil drive too.

Do you think a sequential read, every hour or so, for a day or so, would be less stressful on the drive, yet spread the lubricant around?

Dwight Elvey
February 7th, 2017, 01:00 PM
One thing that hasn't been mentioned is that we a lumping
stiction and dry bearing grease into the same pile.
These are two different things.
Heating a drive up to get the disk turning is not the same as
getting a head that is stuck to the surface to budge.
Dwight

Druid6900
February 8th, 2017, 04:59 AM
One thing that hasn't been mentioned is that we a lumping
stiction and dry bearing grease into the same pile.
These are two different things.
Heating a drive up to get the disk turning is not the same as
getting a head that is stuck to the surface to budge.
Dwight

Dwight, as always, you hit the nail right on the head. Since either condition could cause the drives to fail to spin-up, either could be the culprit.

However, since, if I whack the suckers on a tabletop, they WILL spin-up when powered on I would lean towards the "heads stuck in goo" scenario. What do you think?

Dwight Elvey
February 8th, 2017, 01:20 PM
It could even be a little of both.
As the head sits on the disk, the air layer goes away.
This was the original stiction.
It wasn't a goo problem it was getting the head to let loose and start
flying again.
Most drives now days park the heads off the surface.
Dwight

paul
February 8th, 2017, 04:01 PM
Wiki has a good section on this subject
https://en.wikipedia.org/wiki/Stiction#Hard_disk_drives

Druid6900
February 9th, 2017, 06:01 AM
Well, regardless of the cause, the ST157R has now been spinning for almost 20 hours, doing a sequential read, then 50 random reads, then a sequential write. I'm running it in a continuous loop.

There have been no errors at all.

One loop of the process takes about 2 hours.

I'm going to continue it for another 4 days, park the heads and let it rest for a day.

If it is successful in spinning up after 24 hours, I'll put a park utility on the customer's computer and instruct him to run the batch file at shutdown.

If not, it's a smaller MFM drive on the hard-card or a SSD.

Stone
February 9th, 2017, 06:42 AM
Since stiction never really goes away just instruct him to never turn the computer off for longer than 20 minutes and it'll probably be OK. :-)

You could run the drive drive from a separate power source so just the drive remains on.

paul
February 9th, 2017, 12:08 PM
Since stiction never really goes away ...
That's certainly been true with the two drives I have stiction trouble with, both voice coil type. They might be OK for up to 2 months but always stick eventually, while the other dozen drives in my collection never have such problems.


...instruct him to run the batch file at shutdown.
The hot water bottle works great for me, might want to suggest that.

Druid6900
February 10th, 2017, 06:03 AM
Well, it's academic now, since I've advised him to go with the SSD solution, which he is.

With the Conner drive, I've found a working replacement and instructed the owner to purchase it (they don't ship outside the US) and ship it to me.

Even I can't battle the law of entropy...

It seems to me that 3.5 inch drives suffer from "stiction" more than 5.25 drives do. I have 30 year old 5 1/4 drives that just keep going and going.

Dwight Elvey
February 10th, 2017, 08:49 PM
If it were true stiction, heat would make it stick more. If preheating
the drive works, it is a bearing grease issue or condensation and
not true stiction.
Dwight

Druid6900
February 11th, 2017, 06:01 AM
If it were true stiction, heat would make it stick more. If preheating
the drive works, it is a bearing grease issue or condensation and
not true stiction.
Dwight

On all three drives, if I give the spin motor a gentle powered-off push, the drive will spin up, run, work and test fine.

The problem reasserts itself when it has been off for a number of hours.

It could still be either cause.

Dwight Elvey
February 11th, 2017, 09:18 AM
Try warming the drive after it has been off for a day.
Bearings will start easier.
Baking it will only make the oil worse.
( Note I said warming, not baking ).
Dwight

Druid6900
February 12th, 2017, 06:09 AM
Try warming the drive after it has been off for a day.
Bearings will start easier.
Baking it will only make the oil worse.
( Note I said warming, not baking ).
Dwight

Define "warming".

I have, in the past, almost entirely with 5.25 inch drives, given the spindle a little shot of WD-40, spun it up for an hour or two, circuit board up, and off it goes. I have a ST-225 I did that to about 20 years ago and it's still working on my XT test jig.

I have a ST-251-1 that sat, with the bubble top off, in an unheated garage for about 10 years. I blew off the platters, lubed up the spindle, put the case back on and it's still working on my AT test jig.

3.5 inch drives don't seem to respond as well.

Like 3.5 inch floppy disks, 3.5 inch hard drives don't seem to have the staying power of their 5.25 inch counterparts.

Stone
February 12th, 2017, 06:55 AM
3.5 inch floppy disks ... don't seem to have the staying power of their 5.25 inch counterparts.My experience shows that the 3" and 5" floppies have about the same failure rates. I've got hundreds of bad floppies and they seem to be equally divided between the 3" and 5" varieties.

paul
February 12th, 2017, 11:57 AM
Hmm, comparing hard disk stiction with floppy disk reliability based on size seems to be tenuous at best!

I checked my 2 GB 3.5" Micropolis again, known to be stuck and I can feel the higher (motor axis) polar inertia when handled compared with a known-good drive.

15 minutes on a hot water bottle at 75 C brought the Micropolis disk housing up to 53 C and now I can hear the disks turning when I handle the drive. It powers right up as well.

Stone
February 12th, 2017, 12:59 PM
Hmm, comparing hard disk stiction with floppy disk reliability based on size seems to be tenuous at best!I don't think he was doing that comparison! :-)

I saw it as a comparison between 3" and 5" drives, both hard and floppy, and that the 5" media outlasted the 3" in both devices, no matter what type of problem they encountered.

Chuck(G)
February 12th, 2017, 01:36 PM
I still get 8" floppies from the 70s, from time to time. Rarely any problems, unless they started life as junk.

1/2" magnetic tape appears to be even more long-lived, although the earlier tapes can be 7 track.

Cards and paper tape, assuming good stock and isolation from critters and water can easily outlast any of the above.

Etching your data into a granite slab probably beats all of those.

In all but the last case, they key is "back your data up periodically"

Dwight Elvey
February 13th, 2017, 05:31 AM
Define "warming".

I have, in the past, almost entirely with 5.25 inch drives, given the spindle a little shot of WD-40, spun it up for an hour or two, circuit board up, and off it goes. I have a ST-225 I did that to about 20 years ago and it's still working on my XT test jig.



Don't use WD-40 on anything you want to keep.
1. it is not a lubricant
2. it leaves a wax substance that is impossible to clean
3. it will absorb moisture from the air and cause corrosion

Dwight

Druid6900
February 13th, 2017, 05:52 AM
My experience shows that the 3" and 5" floppies have about the same failure rates. I've got hundreds of bad floppies and they seem to be equally divided between the 3" and 5" varieties.

I needed to make up another set of all my diagnostic disks as some get clobbered in use.

I took 10 random 3.5" disks, DD & HD and an equal number of 5.25" disks out of the drawer I throw them in and the results were as followed;

3.5 " - 3 out of 10 formatted fine on the first try, a 4th did after running a bulk (video) eraser over it. The remaining six crapped out with bad track 0.

5.25" 9 out of 10 formatted first trip through and the last would format for love nor money.

This is just from my experience. YMMV

Druid6900
February 13th, 2017, 05:57 AM
Don't use WD-40 on anything you want to keep.
1. it is not a lubricant
2. it leaves a wax substance that is impossible to clean
3. it will absorb moisture from the air and cause corrosion

Dwight

Dwight,

I know people rail against WD-40, but, I've had great success with it.

If it makes you feel better, I usually hose it down a couple of days later with cleaner/degreaser.

Wax on sticky bearings doesn't seem like a bad thing to me.....

Druid6900
February 13th, 2017, 06:05 AM
Back to the matter of heat for stiction, I discovered something promising.

The DEC SCSI drive I was talking about earlier has been sitting on my desk in front of a south facing window for months now and, just for S & G, I thought I'd plug it into a PSU and see what happened before I tossed it out.

Lo and behold, it spun right up, so, maybe low and slow is the way to go with the stiction problem, over time. I know it's just one dot on a chart, but, I'm going to line up the affected drives and, if we get some more sun, see what happens at various times in the process.

I'll even try to monitor the number of hours of sunlight they are exposed to.

Perhaps the purchase of an infrared bulb is in order.....

Stone
February 13th, 2017, 06:20 AM
This is just from my experience. YMMVI just looked at my pile of dead disks and there were roughly 100 of each.

Druid6900
February 13th, 2017, 06:27 AM
Yes, but, how much longer have the 5.25" disks been around than the 3.5" disks?

I've just found that 3.5" disks don't last as long, from package opening to trash can as 5.25" disks.

The fact that the larger ones don't have the "dust shield" that the smaller ones do makes it even more pronounced.

Stone
February 13th, 2017, 07:45 AM
Yes, but, how much longer have the 5.25" disks been around than the 3.5" disks?The same time.

I bought all of them in the early 1990s. I bought thousands of them back then and I still have some. They're the disks in my SIG.