Restoration questions about 122 key Model M's

masilver · 31 Jul 2018, 04:41

I have three boxes of Model M 122 key keyboards.

I need to replace the foam on a few. Does anyone know where to find sheets of the stuff? I know Unicomp offers it, but it's at least $10 per sheet.

Also, has anyone had luck installing a USB hub in a model m? What about an LCD screen?

I've had problems with soarers converter losing keystrokes under heavy load. Has anyone else had that problem? I find qmk to be more reliable. Does this match anyone else's experience?

Thanks, in advance.

...Michael...

mark201200 · 31 Jul 2018, 05:17

Model M's don't have foam afaik, and I never had any problems with the converter on my m122, maybe you should check your wiring

masilver · 31 Jul 2018, 05:56

Thanks, I'll take a look at the wiring.

I don't know if it's foam, because it's very thin, but there is definitely some sort of pad between the membrane and the buckling springs.

orihalcon · 31 Jul 2018, 06:01

Yeah Model M's don't have foam, unless you mean the rubber sheet that is in there for dampening, though that usually doesn't degrade. Or perhaps you are referring to the membrane? I guess knowing why you think the "foam" needs replacing on some might shed some light. Could just be in need of a bolt mod if certain keys aren't registering and there's a bunch of missing rivets on the backplate.

What produces the heavy load that causes it to lose keystrokes? You mean like very quick typing? If it's key combos, could be if you are pressing more than two keys at once that could cause any model M to drop due to the 2KRO limitation of the membrane. Though there shouldn't be a difference between QMK and Soarer's for that reason though.

I don't see any reason why you couldn't put a USB hub in a Model M. I put one in an original NES controller about 10 years ago so that I could have a flash drive in there along with a crappy Dell keyboard controller so that files could be stored within the controller and so that controller buttons would produce keyboard presses that could be used by an NES emulator on any OS without drivers. There's way more space inside a Model M than an NES controller if I do say so myself

This was of course before I knew anything about Arduinos, so you'll have to forgive how MacGyver'ed it is. Basically Dremeled as much of the original PCBs as I could, and it all worked, even without short circuiting! Come to think of it, this was my first keyboard project of all time, before I really even knew/cared about mechanical keyboards. How times have changed

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End thread hijack.

masilver · 31 Jul 2018, 06:19

Yes! It's a rubber mat. One has severe rust stains.

I can't imagine working inside an NES controller. And to think I thought a 101 key model M was tight.

mark201200 · 31 Jul 2018, 18:53

masilver wrote: Yes! It's a rubber mat. One has severe rust stains.

I can't imagine working inside an NES controller. And to think I thought a 101 key model M was tight.

so it's the one that sits between the flippers and the membrane, right?
You can wash it, it should clean wery well, or you can use the keyboard without it.
If you really want to replace it, you can contact Unicomp, I think they sell them.

fohat · 31 Jul 2018, 19:49

It is under the membranes, isn't it?

I would give the rust stains a good soak in vinegar and then scrub with soapy water. The new ones from Unicomp are thin white latex instead of thick black rubber and are an improvement, but would get pricey for several at $10 each.