How to Fix Your Quantum SCSI Hard Drive

Got problems with your Quantum SCSI hard drive in your old Mac? Me too buddy, me too. Problematic! The problem relates to foamy rubbery bump stops for the head which become sticky and gloopy over time.

Shout out to thetechknight who was the first online I found who identified this problem. Itchyspuds also has a video on a slightly different model.

Thanks for all the comments, it's always great to talk tech with new people!

[RetroSpector]

12 minutes in and you are going to be a legend if you get this drive up and running again ! Really enjoyed it so far ... also worked on one of those today IDE version from an old IBM computer. my second brake bumper was underneath the platters so I had to remove everything. (head assembly, platters, Drive worked for 1 day after the fix...after that never worked again. Coil wire got separated from one of the heads. :(

[IntexDigitalSound]

Thank you for this great video. I was able to save my Amiga 3000 HDD thanks to you. To remove the old sticky black stuff I used acetone, which worked fine. To replace the rubber stoppers I used 4 layers of shrinking tube. Looks like original and works fine.

[zuctronic]

I just put a tiny piece of masking tape over the sticky rubber and it solves the problem. It's possible to do this (carefully!) without removing the whole magnet, since that's a source of trouble more often than not!

[bthatguy]

Going to go out on a limb and suggest a set of JIS (Japanese Industrial Standard) bits. Much less likely to cam out, and may be the actual spec for those screws.

[funtimess]

I loved how casually you tap the drive read head with fingers...NO FEAR :) lol

[Electrotat]

Thanks for this, I have 4 Mac classics that need the hard drives repairing, worth a shot 👍🏼

[efrog]

How about sucking the flakes with a vacuum cleaner while drilling?
I've got one Quantum ProDrive LPS 105S that stopped working yesterday, spins nicely but no head movement is heard, doesn't identify with any size in Windows (using a SCSI controller) - the other five drives I have show up nicely. So I'm considering this method...

[tommasopetrella]

This is the same thing that happens to old tape drive belts over time. the rubber they use must be the same. great video ! it is good to know what's causing the problem and to see it first hand. Thanks!

[realgroovy]

Nice repair! if only Quantum thought of that in the first place, but they would have probably realized nobody would be using a computer for more than 10-15 years anyway so they decided to go with the cheaper option, also I'd probably scan that drive to see if it has any bad sectors!

[juanfurones]

This absolutely works! Brought back to life my IIsi! Top!

[jeremybender]

Thank you very much. Just fixed my Mac Classic II. I use it to run Sound Designer II to interface with my Emulator II

[alexshepherd]

Interestingly your ProDrive is similar to a much-older “Plus” drive made by Quantum and found in an SE/30 that I’m dealing with today.

Previously I’ve dealt with a different ProDrive from the 90s which is newer and cheaper - in an LCIII - and one of the bumpers was under the platters. To solve that one, I made an odd-shaped replacement bumper using my 3D printing in TPU, that pushed in beside the magnet plate. It had to be just the right thickness to prevent the head arm from reaching the original bumper. Worked well on the third design attempt (if it’s too thick, it can’t find the tracks!)

On this other type, I just 3D print a cylinder of the right diameter to fit over the dowels. Thanks for all the inspiration anyway - mainly for using the very best quality screwdriver to get the magnet plate screws out… and also it was nice to use an 8mm socket to get that nut off ;)

[tjlazer]

I just fixed mine without removing the metal bracket/magnet.  I cut a long thin strip of clear packing tape.  The thicker kind and inserted in between onto the rubber stop and then cut it to length.  I then used a small screw driver to apply it all around the stop.  What it does is isolate the bump stop with the tape, thus not allowing it to stick anymore!  Works perfect now.  And a quick easy job.  I would really caution removing the heads from the platter.  On another drive I killed it when I tried to do it like this...

[orinokonx]

Nice video, glad you did this. Funny how there are people crying on the Hackaday comments about your technique - they don't realise how clunky the older gear is, methinks.

[supercade]

OK, so I have a quantum drive that’s acting up and I thought that this was the issue but the head seems to be able to move but it’s still coming up with ?

[Jenny_Digital]

I do have an idea as it happens. What about making a glove box with filtered air to work on these things in. I'm not sure what it would take to make it good enough but it's an interesting problem. I shall be ruminating all week on this.

[dialupdude]

My 40mb Macintosh drive wasn’t working but I opened it using this tutorial and tried booting it with the cover off and now it works fine! I put the cover back on and it continues to work. Not sure what happened there.

[maxbecker]

Tipp, use a strong mangnet on the drill bit. It becomes magentic and if you drill carefully in little stepps and remove the metall pices on the drill bit periodically, you are able to drill the screw without metall pieces all around your hardware

[bthatguy]

If you want a good bumper, maybe AC quality (the green ones) o-rings stacked on the post would work.

[aaronstachowiak]

Cant believe this worked for my new vintage Macintosh LCIII