restoring my first cube

I acquired this lot a little over a month ago:



When I got it, the system booted into a fresh install of OpenSTEP 4.2 that had been installed on the internal HD, the display worked, MO drive did not work, and I didn't try the CD-ROM or printer.  First thing I did was image the HD using BlueSCSI's initiator mode and confirm that I could boot off the BlueSCSI because the HD sounded like it was going to die any minute:




I then disassembled *everything* and ordered replacement caps.  The only places I saw obvious signs of leakage were in the PSU and CD-ROM, but I'm just going to re-cap it all as a preventative measure.  So far, I've re-capped the PSU, monitor, sound box, and logic board and all are working well.  The image on the MegaPixel is *crisp* after tweaking the various adjustment pots.

Everything was super dusty and dirty too, but warm soapy water, some elbow grease, and an air compressor sorted that out.  The display and cube are now both fully recapped, cleaned, and reassembled, so next are the MO drive and CD-ROM.

I also modified this model (https://www.thingiverse.com/thing:4706014) and made a BlueSCSI bezel and drive bay mount for the cube...came out pretty good:







I chose to make it two pieces because making a tray attached to the bezel was going to be flimsy, difficult to print, and would have required slightly more disassembly of the computer to remove the BlueSCSI if I ever need to.  Rather than try to fiddle with precise measurements to get everything to line up, I just made a block, screwed the regular BlueSCSI bracket to it, and then marked screw holes in the sides of the block once I got everything to line up.  It's super solid.

Great work! I hope to follow in your footsteps soon on the recapping and my BlueSCSIv2 kits will be here tomorrow.

I hadn't paid attention to the initiator capacity for cloning drives yet - looks like a great idea! I don't think the install that is booting on my cube right now is anything unique (seems like a fresh 3.3 from what I can tell), but still looks like fun to preserve it for the sake of it.

Still a few cable parts away from getting my N4000A online, so fingers crossed it's functioning and anywhere near as nice as yours looks.

Quote from: halfpress on December 08, 2024, 10:04:55 PMI hadn't paid attention to the initiator capacity for cloning drives yet - looks like a great idea! I don't think the install that is booting on my cube right now is anything unique (seems like a fresh 3.3 from what I can tell), but still looks like fun to preserve it for the sake of it.

It's been super handy for me a couple of times for easily transitioning an existing install from a spinning disk to an image usable with something like a BlueSCSI (like I did here).  It's also been useful for extracting and archiving installed software from found machines because I can easily mount the resulting image in an emulator and copy stuff to the modern host machine.

Quote from: KennyPowers on December 09, 2024, 09:39:42 AMIt's been super handy for me a couple of times for easily transitioning an existing install from a spinning disk to an image usable with something like a BlueSCSI (like I did here).  It's also been useful for extracting and archiving installed software from found machines because I can easily mount the resulting image in an emulator and copy stuff to the modern host machine.

Oh, absolutely - the value of it sounds fantastic and I'm thinking of several useful scenarios. Especially emulators!

Great pics! I'm about to embark on a recap of my N4000 (earlier than the N4000A with the mic as in your setup). Was curious how difficult you found the recap and pot adjustment process?

Quote from: pl212 on December 12, 2024, 05:31:57 PMGreat pics! I'm about to embark on a recap of my N4000 (earlier than the N4000A with the mic as in your setup). Was curious how difficult you found the recap and pot adjustment process?

Not difficult at all, though I have a desoldering gun (Hakko FR-301) for through-hole caps and some cheap hot tweezers for the SMD caps on the sound board, so removal was pretty easy.  I assume you know to tweak the pots with a non-conductive tool.  Take your time and be gentle when disconnecting the CRT neck too...I'm always terrified of cracking the neck on an irreplaceable CRT  :o

I completely recapped, cleaned, and lubed the magneto optical drive.  However, I'm getting no signs of life from the drive.  I don't hear anything when powering the drive up (have confirmed voltages at the 4-pin molex connector).  It also won't ingest disks.  I can push the disk in most of the way and then it stops where I believe the eject motor is supposed to begin ingesting the disk (I'm just guessing...have never used a working one of these drives).  With the drive open and disconnected, I can get it to ingest a disk by manually turning the eject motor after inserting a disk to the aforementioned point where it encounters resistance.  Thoughts?

Wow, that's very cool. Great work.  Maybe I need to send my MO drive to you for repair! :D

Quote from: eagle on December 30, 2024, 06:33:40 AMWow, that's very cool. Great work.  Maybe I need to send my MO drive to you for repair! :D

But...my MO drive doesn't work ???

That could be either the digital or analog board. There's not much to go on unfortunately. I would check that power is at least getting to both boards. 

I turned my attention to the DOA external CD-ROM.  After disassembling it, it quickly became clear that all of the surface-mount electrolytic caps had barfed all over the board:



Several of those traces looked very worrisome.  I cleaned the board with vinegar to attempt to neutralize the electrolyte, and then gave the whole thing a thorough cleaning with 99% IPA.  The original caps were all removed, as well as two ICs that were in the splatter zone and I had replacements for.  I then scraped the corrosion off of all of the solder pads under a microscope and re-tinned them:



Finally, I scraped any questionable traces down to the copper, re-tinned them, confirmed continuity, and installed new ICs and de-rated tantalum polymer caps:



I also re-capped the drive's power supply as it reeked of fishy-smelling electrolyte from all of the through-hole caps inside leaking.  After confirming good voltages out of the PSU, I reassembled everything and...it lives!

The traces around the 100uF caps are usually the worst to deal with. I just did a lot of 10 and all but 1 had trace damage.

Quote from: barcher174 on January 15, 2025, 04:06:29 PMThe traces around the 100uF caps are usually the worst to deal with. I just did a lot of 10 and all but 1 had trace damage.

There's a similar spot on the pizza-box Mac LC logic boards that *always* has cap damage due to the high concentration of leaky caps in a small area.  Two of the ICs flaked off of this one when barely touched: