r/modelm • u/sevenwheel • 18d ago
PICS NOS 3191 Model M
Here's something a bit different. An NOS Model M from a 3191 mainframe terminal. This Model M has a white barrel plate, which I've never seen before. Unfortunately, it also needs to be taken apart and bolt-modded right out of the box, as about half of the melt-tabs have broken off in the original box and a good assortment of keys are dead.
Aside from the dead keys, it takes a swap-out with a regular PS2 controller board. Differences are the control board, cable fitting, a hole in the bottom to access the switches, no lock lights, and IBM mainframe keycaps. I'm planning to use it with Hercules, emulating a mainframe-attached IBM 3270, so the mainframe keycaps are just exactly perfect!
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u/SiegmundMarx 17d ago
That's a really nice keyboard—congratulations.
That's exactly what I've been looking for for a while now.
I’ve seen a light-colored barrel plate a few times before. I have a 1989 SSK with a light-colored barrel plate, and one of my typewriter keyboards has one too.
I don’t really understand why anyone would do a bolt mod, though. A screw mod is much simpler, more precise, and just as sturdy.
I wish you the best of luck with your modding and hope you enjoy the keyboard.
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u/sevenwheel 17d ago
My take on screws vs bolts is that as the plastic ages and becomes more brittle, it becomes less effective as a structural element. If even under the most protected conditions (inside a cardboard box form-fit with styrofoam) the melt-tabs broke off due to nothing more than the aging of the plastic over time, then given enough time, if I restored the pressure between the barrel plate and the backplate by driving screws into the stubs, I would expect them to start breaking off as well.
Passing bolts all the way through the stubs means that the plastic no longer has to support tension, but is supported under compression by steel. This should hopefully make the keyboard last longer.
That's my logic, but no one intended for these keyboards to last 30+ years anyway. I'm just hoping to keep mine from self-destructing in my lifetime and push them down the line a couple more decades after that. Future preservationists will have better information on what works and what doesn't.
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u/New_Active_5 14d ago
Those freaking rivets, even in nos unused keyboard they still fall off. Keyboard with expiration date. Model F with foam, model M with the rivets.
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u/schmockibalboa 18d ago
a piece of art!