Good afternoon —
I recently came into possession of the IBM Model F keyboard that came with my Dad’s IBM AT that he purchased back in 1984, and I’m hoping to bring the keyboard back into service in some way. The inner foam has, as expected, disintegrated into a fine powder, and due to having been stored in a humid basement for something approaching 30 years, the top plate has corroded to the point where it’s no longer black, it’s actually completely white on the top instead, and the foam residue on the inside of it has left behind a rather disgusting, sticky, flaky mess that seems like it might be more trouble to clean up than to try to rescue.
I saw that you have a foam insert that, after a little trimming with some scissors, will work with an AT-layout Model F (the F107 layout, if memory serves), but when I look at the repair kits available, it seems that there are kits for every Model F except that layout. Is there a way to obtain a repair kit that has the correct foam insert for this layout?
I’m also hoping that you might be able to provide (or know how to source) a top plate for the same layout, since I’m not sure that I can strip the top plate of all of the corrosion and re-paint it without it winding up worse.
Any hints or advice would be very welcome.
Thank you!
~~ Matt Balmer
Great Matt; glad you were able to clean those springs up nicely.
Converting the Model M layout involves destroying all of the rivets and performing a bolt mod, which requires carefully drilling 100 or so holes in the plastic. There’s a risk of cracking the barrel frame. I don’t recommend it unless the keyboard is non-functional. I offer only one piece keys.
After some effort, the vast majority of the mineral deposits have been removed from the keyboard plate. I took a couple of the springs and dropped them in some distilled water, and sure enough, after about six hours, the deposits had dissolved into the water, and they were nicely clean after allowing them to air dry over the course of a couple of days. Since that seemed to work, I took the remainder of the springs, and soaked them in a distilled water bath, and they came out nicely. Here’s pictures of the ones that went through the bath first.
The source of it all was definitely being exposed to really hard water — I also got my hands on an old Sun Sparcstation 1 that was stored in the same area, and it had the exact same kind of damage. It was clear that water had dripped down onto it and worked its way inside; the same white crusty junk was all over the inside of the case. It had even managed to crawl its way up into one of the drives’ spindle motors and had completely ruined it.
As I understand it, the keyboard PCB is capacitive, so if it’s plugged in to a device, I should be able to just tap the keypads with a keyboard flap to get signals out of them.
I also have an M122 that I’m working on that uses the 3179 terminal keyboard layout. I’d like to re-legend it for regular use and switch it to an ANSI layout if possible. Are the keys you sell the kind that are just the cap, or the full cap and stem? The keys I currently have are the kind where you could pop the cap off to re-legend it without having to pull the whole key stem out.
You could try to clean the springs (plain water so as not to affect the flippers?) but I would not remove them from the flippers as the precision attachment is important to the original sound of the keyboard. I have no recommendations for this, so I suggest starting with cleaning just a few. I’ve never seen a substance covering the springs that prevents normal sound and operation, so I can’t say for sure.
While disassembled you may want to just test that every key functions reliably (just plug it in with the PCB tightly bolted with both controller bolts/screws to the gold bottom inner assembly plate and place a flipper on top of the keyboard with a keyboard tester web site open). Better to test now than to install all the keys and then have to remove all of them when there is a bad row or column, or worse.
For the corrosion, you could follow recommendations for rust removal online (soaking in vinegar for a few days and then scrubbing, etc.) but other than looks even a ton of corrosion does not affect functionality.
After looking closer, what I thought was corrosion…isn’t actually corrosion, it’s mineral deposits from being exposed to hard water. I tested a small corner of the plate with rust removal solution and it just laughed at it. There is a small amount of actual rust on the plates, but nearly everything was mineral deposits.
I successfully disassembled the keyboard all the way down to the circuit board. The board itself looks largely fine, although there are a few places where some of the solder mask has had some moisture ingress (black spots over traces). Nothing serious. The solder points from the controller also had the same white deposits on them as the outside of the case, but after a little poking with a multimeter, it didn’t seem to affect any of the connections, so I’ve left that alone.
Regarding the keycaps and barrels, those got tossed in a plastic tub with hot water and dish soap and allowed to sit for a day, and then allowed to dry for a couple more. They cleaned up beautifully.
I don’t know that I can say the same for the flaps and springs. When I tried pressing keys prior to disassembly, the keyboard sounded…strange (the click sounded dull and quieter than it should’ve), and pushing keys felt oddly stiff. When I opened it up and got the spring assemblies out, nearly all of them had the same white deposits on the springs as the outside of the case. While I was able to knock a good deal of it off by simply flicking the springs with my finger, it was clear that it was interfering mechanically with the springs themselves and that was why things felt and sounded odd.
I’m in for the long haul on this keyboard as I want to get this keyboard up and running along with the machine it went with (it’s personally special to me), but I’m looking at these springs and wondering just whether they’re able to be saved or whether it just makes more sense to order a full set of replacement flap/spring assemblies.
Let me know what you think.
~~ MB
Great Matt; glad you are restoring this great keyboard! I have restored many such boards in the condition you describe. Yes, you’ll need to take a toothbrush to scrub the foam flakes off each of the barrels.
Follow the instructions on this page to order the right foam for your board (see the description for details): https://www.modelfkeyboards.com/product/extra-inner-foam-f62-f77-f62-split-shift-f77-split-shift-f107-f122/
Then you can order some replacement flippers with springs to have as spares. Most of the originals are probably still good even if they appear rusted.
To clean the case and keycaps, I recommend generic non-branded melamine foam sponges and water, with a few drops of dish soap in the water. Do not scrub hard or you will wear the surface texture. I usually put the keys in an ultrasonic cleaner for a half hour and then let air dry for a few days (do not try to speed up drying with a hair dryer etc.). Never clean the flippers and springs except by dry cloth; do not try to remove rust from the springs or you’ll damage them. They will almost always work fine even if rusted.
For the corrosion, you could follow recommendations for rust removal online (soaking in vinegar for a few days and then scrubbing, etc.) but other than looks even a ton of corrosion does not affect functionality. All those folks who strip the rust and sand and then spray paint are just doing it for aesthetic reasons. Once you put on the keys it will be near-impossible to see anyways.
If this is too much please do sell or give your board to someone else as there are many folks willing to do this if it means they get to own and use a Model F!
And of course if you like these old boards I recommend considering one of the brand new Model F keyboards which don’t require restoration.