Plus Hardcard 20 and 40 Postmortems + Channel Announcement
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- Опубліковано 17 жов 2024
- I try to figure out why three of my Plus Hardcards died and whether there is feasibly anything the retro community could do to repair them when they die.
New channel:
/ @pcretroprogrammer2656
When ADB II's video feels not enough... YES PLEASE
The IPA shouldn't leave any residue, and is probably safe to use. It might be difficult to remove all the gunk though. Perhaps something else would be more efficient, like maybe WD40, and then IPA to remove any oils left by it. It's really surprising the amount of gunk on some of those platters. I really have no idea why the drives aren't spinning properly, but while the spindle might move freely, perhaps the drive mechanism isn't, which I guess is inside the assembly at the very bottom. Maybe there's a degraded belt or something. Maybe the pads on the heads are also "sticky". It's probably quite hopeless to fix though. Kudos for trying!
Us Aussies love using the term "completely borked".
The new channel looks like the exact thing I've been looking for, for quite some time now. Thank you sir!
Very informative video, even though nobody will probably repair any of these drives for good. They may still make up a nice show piece for the shelve though.
I have a 50MB version, new, still sealed in the box :D
I believe those were more reliable, so it probably works if it isn't repackaged.
Yeah, more hdd corpses, thanks for showing, was quite interesting!
The heads stick together because they are so smooth - like gauge blocks. Originally there was a silicone lubricant on the disks. It has to be very very thin so the heads can glide over it.
This exactly! Also, when the drives aren't used for a long long time, the pressure of the heads slowly squeezes the lubricant out underneath so the heads begin to stick to the platter. Those were the marks you could see on the platter, the thin layer of lubricant was missing. Now, when the drive is powered down, it tends to stop at exactly that spot where the lubricant is missing, so it will stick every time.
I'm tempted to try using some silicone or PTFE spray to re-lube the platters…
More programming! I'm sold.. subscribed!
Can you post a copy of that divide software? I've been looking for that for ages - I have a couple hardcards I'd like to try and recover.
I am not sure which divide software you are referring to. In the video I make mention of software for the hardcard, which is here: ibm-pc.org/firmware/other/plus%20hardcard/plus%20hardcard.htm Other than that, I have long since forgotten what software I was using.
@@PCRetroTech That's what I was looking for, thanks!
@@compu85 did the hardcards work?
Hi, Can anyone tell me where to download the HardCard 40 utility programs? I am going to try to repair my HardCard Plus40 that suffers from Stickage by removing the rubber pumper that has turned to goop. I saw another video where the guy fixed his drive in a Compaq portable computer by removing the gooey rubber bumper and replacing it with heat shrink tubing that he built up layer-by-layer. His drive worked after that. I'm going to try to find rubber washers or gaskets for my fix. I think the outer diameter of the bumper is 8mm and I'm going to guess that the spindle it sits on is 5mm.
Now I'm a bit worried. The MFM in my 286 machine died and I got my hands on an NOS Hardcard II XL 50. It is about 2 to 3 years newer than the ones you have and wonder if it suffers from the same issues. I guess the only way to know is to open the box and install it.
I've never tried an XL, but good luck.
Ha, literally 30s after replying, I saw a working XL 50. So you have a chance!
It's sad that these are so unreliable, they are perfect for retro PCs.
Agreed, would be cool if there was a modern version that could be made. (Although it’s kinda sur planted by the XT-CF card)
Could some sort of magnetic resistance in the motor be the reason you had to use so much force to make the platter spin? Maybe there is a fault in the motor drive? Just throwing that in the ring. When it is all still sealed, there could have been off-gassing from the deteriorating rubber that has distributed oily, sticky residue around the enclosed space and onto everything. You haven't completely given up yet though, have you? :-)
The motor itself span freely. I think the heads were magnetised and sticking to the platters. They probably need demagnetisation.
I think you could be correct about the off-gassing of the deteriorating rubber.
I have given up on these drives by now. The electronics actually failed due to my repeated attempts to get the drives to spin up. If there is a way to successfully repair these drives, I haven't found it yet.
In another drive the tiny wires to the heads had snapped. There is no possibility of repairing them without special equipment. Those wires are about the size of a human hair.
Unfortunately stiction is only one of the issues the drives suffer from.
@@PCRetroTech Sometimes I wonder about my wild theories :-) Sounds like you have spent some time on these drives and done all you can.
These things didn't even work well back in the day. Even in 1992/1993. When they were only a scant few years old, only about 1 out of ever 5 would actually work..
Oh wow, really!? I had no idea they were that bad!
@@PCRetroTech Yeah, good idea, Bad implementation. These were not the only attempt at this back in the day. Kalok (and some others) tried this. With standard components. They used a standard Kalok 3.5inch RLL drive, Standard 8 bit controller card, standard ribbon cables, and a power connector that connected to the card. All on a frame that sat in the card slot. It worked great. But it was noisy in the card slot. I remember just buying a bracket for the drive bay and taking apart and pitching the frame.
@@Alcochaser Yes, I've seen a few of those.
A few thoughts: (The usual caveats apply. These are all desperate measures to revive drives that would otherwise be trash. Any fixes may only be temporary, YMMV, at your own risk, etc. No comments about just trashing them, or whether or not it's worth it are necessary here. Of course it's not 'worth it' unless you think this kind of thing is fun and interesting. If you do, you get it, and if you don't, move along -- nothing to see here.)
I wonder if the (in)famous 'freezer trick' would be a more gentle way to address the sticktion issue than rotating the drive. Assuming that freezing and thawing the drive does un-stick the heads, if there is any damage, it will be localized on the disk, won't dig a groove through an entire track, and won't be as likely to rip heads off.
Does anyone know that silicone lubricant would be bad for the disk platters? If it's thought that silicone would be relatively benign, I wonder if a light coat of it would keep the heads from sticking in the future. If not silicone, is there any other easily available spray lubricant that would not damage the platters, and also might keep the heads from sticking?
One issue with lubricants of many kinds is that they can get gummy when dust settles in them. Dust is already a concern for HD platters. There are several videos on UA-cam about building a very inexpensive clean box using a vacuum cleaner hose and a HEPA vacuum bag.
Would there be any sense in designing a 3D printable comb or wedge assembly that could gently hold the heads apart enough to keep the heads from coming into contact with each other in case the platters need to be removed or replaced? Is there any scenario in which platters could successfully be transplanted?
So I propose the beginnings of a protocol for dealing with these drives upon receipt:
1. Remove the plastic cover, possibly somewhat heating it to soften the adhesive.
2. Freeze the drive to un-stick the heads.
3. When it thaws, put it in a homebrew clean box, open the drive, and see if the platters move freely. Maybe push a purpose-made comb between the head arms to make sure they are free. Maybe screw the drive to a bracket that holds it vertical while being serviced, so that any stuff falls down and away from the platters.
4. Check for rubber stopper gumminess. Replace with a suitable alternative. I've seen someone use a section of vinyl tubing to fix a similar problem on Quantum SCSI hard drives.
5. Maybe lightly spray some kind of benign lubricant on the platters to keep future stiction from happening.
6. Reassemble in the clean box.
7. Test drive in computer.
Thoughts?
I had a hard drive repair industry expert comment on one of my videos and he said that a home made rig to suck air with a vacuum cleaner is a very bad idea. He also mentioned that many of the compounds that one can use produce outgassing, which destroys platters, so you need special chemicals.
In this case I believe the most likely issue is magnetisation of the heads. This can only be repaired by opening the drive. One then needs a special comb device to spread the heads from the platter. One could then use a demagnetising loop. However the problem is this can't be done in situ due to the magnetic field. This means complete dismantling of the drive, which requires a bunch of precision equipment. In particular the platters must align precisely. There are also drive specific calibration procedures, which we simply don't know anything about.
I'm now very uncertain there is anything we can do as hobbyists without extreme levels of dedication to repair these particular drives. One might occasionally get lucky, as I once did with a new unsealed drive of this kind. But this drive eventually died just like all the others, and it was flakey at best when it did operate.
CONTINUITY: The transition at 28:22 is somewhat confusing. There's a change from a platter shown before then and described as "really totally ruined", and a platter (side) announced afterwards with "this is the other side of the platter" and described as having "not much damage here either". Are these different sides of the same platter or different platters? (The different backgrounds/cloths suggest the latter.) It's fairly contradictory. PS: What's also confusing is that around 31:58, you mention you took the 40MB drive's platters out, but then at 36:18ish you say you'd (only later) have to "pull the drive apart".
It's a continuity error from editing too harshly to get the time down. I had to leave a lot out of this video and actually confused myself in the end at the order I did things. The video would have made more sense if I omitted this section entirely. Just take it as another random example of platter damage from an unspecified platter.
@@PCRetroTech Thanks for clarifying. I also edited the above comment and added a postscript pointing out another continuity issue.
A third continuity issue is that you mention the successful IPA platter cleanup twice, both at 40:10 and at 43:04.
I also don't get why head movement when the disk is at rest would cause a scrape but head movement while the disk is spinning wouldn't.
Appreciate the content though. Some of your newer featured hardware I wouldn't consider retro (yet), but this is truly retro.
@@ropersonline When the disk isn't spinning fast enough, static friction can cause the heads to bounce rather than glide. Dynamic friction will also cause damage eventually of course. Some claim that when the disk is spinning rapidly a layer of air exists between the head and disk. I don't know if this is a myth or not.
What happened with these drives is that I found both of the platters in the 40mb drive looked damaged in places, so I tried replacing them one at a time with the relatively good platter from the other drive. I had other problems not shown on camera which made this particular story hard to tell on film, so I had to abandon it. Ultimately it wasn't successful anyway, for reasons unknown. Probably these platters are low level formatted at the factory and not intended to have platters removed and/or swapped.
@@PCRetroTech: "Some claim that when the disk is spinning rapidly a layer of air exists between the head and disk. I don't know if this is a myth or not."
@@ropersonline No, some hard drive heads are angled up at the front so they scoop air in under them. This is supposed to keep them off the surface. But exactly which drives work this way, I am not sure. There seem to be multiple different mechanisms (patents and all that), and I've no idea which is the most common way of dealing with that problem, or which method is used in these drives. I'm pretty sure mine were scooping dust and grease, not air.
I have read somewhere that letting the heads touch each other damages them
They are very delicate. It wouldn't surprise me.
@@PCRetroTechI am thinking of buying head combs as I guess that hard drive surgery will become the norm with those old drives
@@krz8888888 It would be interesting to hear if you have any more luck repairing these than I have had. Admittedly I probably could have gotten one or two of these drives partially working if I hadn't made silly mistakes. Still, there's not exactly a tutorial on it somewhere, so one has to learn somehow.
@@PCRetroTech It seems like a fairly unforgiving process. That oil is a mystery to me, could it be vaporizing from the melty rubber ? In any case it was a very interesting video, happy that youtube recommended it
My guess is it’s evaporating from the head assembly bearing and depositing everywhere else. Maybe that’s what makes the heads stick, although magnetization seems plausible too.
id trie these in a modern desktop pc
They won’t work, or even fit, as no PC made within the last 20 years has ISA slots.
You need some branding, at least a channel icon. Probably helps with the algorithm too
Yep, you are certainly right. I'm still waiting to see if something comes up organically, instead of just making something up.
How about some blown or exploding caps in comic style?
Another channel "split" for algorithm...
swap the drive with a new one
rip the stupid heads off as you did anyway and then try to boot it, then you see it it is the head or the motor, what is such a big mystery about that. my god, what a clickbait. First he says he uses those to find out something and then he destroys them and does not know anything either.