Restoring a 1993 IBM Model M Blue Label keyboard.

This is the second one I've gotten from this eBay seller. The first one came in a priority mail box packed with brown kraft paper,

and was damaged in shipment because of it. This time the seller promised me he'd pack better. This turned out to just mean more paper.

Also note he used free USPS supplies to ship FedEx.

But it made it through pretty much okay. In fact it looks quite nice.

Birth certificate says Nov 17, 1993. Cut cable is visible here. They didn't leave me much to work with.

Pretty clean inside too.

Most of the rivets are still there, but there's some rust. A bit where the production stickers went, and some at the corner.

This is interesting. A label over a label. There were also two production tags, which we'll see.

Here they are. They fell off on their own. Two different part numbers, two different dates. The later one matches the big label.

Mainly just dusty inside. The LED board is crooked, though. We'll fix that.

This is so clean that I didn't even need to wash it. Just wiped it out.

A few broken rivets, but many of the remaining ones are fragile, and I want to deal with that rust, so I took it apart.

Rust never sleeps.

Teardown in process. Note the rust left on the membrane.

Looks clean.

Springs and flippers out.

This keyboard has one-piece keys. I've always known they exist, but it's the first time I've seen them.

I bought this 15-foot m/m PS/2 cable thinking I could cut it in half and get two replacement cables out of it. However...

...it turned out not to be shielded. I tried it out anyway but it was only partly functional.

I replaced it with a Tripp Lite keyboard extension cable that I cut the female end off. That was shielded and worked fine.

Deciding what to do about the backplate. I masked off the label, removed the rust, and painted it flat gray.

This turned out to be a bad move, as I'll explain when we get there.

Here is how I drill out the rivets. Note how deeply the bit is chucked in. Just about 1/2" protruding.

Remember I said painting the plate was a bad idea? The paint must have been old, or reacted with the galvanizing, because it simply didn't dry.

Two days later it was still tacky. So I had to strip it and start fresh. This was a shame, because I'd carefully masked off the labels.

I knew they'd never survive a paint stripper step, so I regretfully scraped them off.

You can see in the picture that the label underneath had a part number and date that matched the earlier of the two production tags.

I don't know if this means the unit was mislabeled and corrected, or assigned a new part number for other reasons.

Here is the plate, stripped and refinished with a different kind of paint. It's actually Duplicolor paint meant for alloy wheels.

Wait, what's that next to the plate? Wasn't that label destroyed?

Yes, it was, but I reproduced it, including the pencil marks. Here the labels have been reattached to the plate with spray adhesive.

Reassembly begins. Flippers and springs in.

These later ones with the thin barrel plates make me nervous. It worries me that they flatten out so much. I'm afraid they'll break.

Rubber sheet and membrane.

Separator sheet and second membrane.

Screws installed and torqued. Ignore my feet and knees.

Here's how the rebuilt cable routes inside the case.

I'm rather pleased with this method of securing the cable to the drilled-out strain relief.

Snug up a zip tie to the cable...

Put a dab of E-6000 adhesive between the zip tie and the strain relief...

And tug the cable to seat the zip tie against the back of the strain relief.

This pulls adhesive into the hole and secures the cable to the relief.

It's alive! Note I repositioned the LED board.

In this picture, the cable is plugged into the motherboard.

The other cable worked when using a USB converter, but not when plugged directly into motherboard PS/2.

The motherboard must be relying on the shield for ground.

All done.

Final photo, in good lighting, suitable for framing or inclusion in a family album.

Postscript: This one was way more trouble than it was worth. The F5 key was mushy. Bad spring.

I wound up having to take it all apart and replace that one spring and flipper.

Fortunately I ordered a few last time I bought something from Unicomp. They sell them for 20 cents each.

I ordered five and they shipped me nine. Nice of them. Turned out handy. The new Unicomp piece is on the right.

The key still feels a little less than crisp, but I think it's as good as it's going to be.

Post-postscript: In November 2022 I transplanted this keyboard's internals into a NOS (new old stock) Industrial case.

Unicomp found a bunch of these in their inventory and sold them off, and I was lucky to score one.

A friend provided the reproduction black label. Looks great this way, doesn't it? And like new.

Want to contact me? Try me at j7l{at}@xec.net.