Model M Rivet Replacement

[o2dazone]

I feel empty inside

[o2dazone]

also new springs/hammers came in from Unicomp. Looks like my evening is tied up after work.

[o2dazone]

Work complete! Took much longer than I had anticipated due to a few complications, I'll outline them here so maybe others wont have the same issue.

-there is one post that you drill into that does NOT have a hole on the steel plate. It's near the right shift key. It kept me from fitting nearby nuts, and warped the barrel plate. I backed it out and everything was golden

-the nuts are relatively hard to fit if you don't strategically go from the outside in. I would do what Ripster suggests and put a nut in each corner then 3-4 down the center. Then get a single keycap and put it in each barrel and test the hammers before putting all other nuts in. This will also be a good foundation for fitting all other nuts.

 To test each switch before putting in the rest of thd nuts, i actually took a spare key and sanded the nubs that hold the key in. That way I could easily slip the key on, test it, then slip it off with my fingers

If you're finding yourself REALLY squeezing the board together to fit nuts, something is wrong. Examine the barrel plate for any warping, or make sure the steel plate is as flat as it can be. Sometimes it gets caught up on the threads of the bolt


I added some rubber grip pad inside the board to dampen the ping. Other than the mechanical sproing from the buckling spring, there's no other sound. Photos and video tomorrow

[drteming]

I recently got 2 1391401's, a 93 blue label and a 88 white label.  Did the bolt mod on both keyboards after reading through the guide and the thread.  This is a wonderful resource.  Thanks to everyone who contributed (Yes, I voted in ripster's poll).  I used the chisel tip x-acto knife to trim off the rivets, but instead of sanding down the post, I used a nail clipper to snip off the residual plastic.  For the pilot holes, I used the soldering iron--worked wonderfully.  Here's the kicker--this is the drill I used:



It a Zimmer #895 micro hand drill that I scrounged from the retired instrument cabinet from the OR.  And no, I'm not an orthopedic surgeon.

[fohat.digs]

Holy **** !

I have been lamenting the fact that there were not at least 2 settings below "Low" on my Dremel.

How is it that this tool does not "walk all over the place" when you start turning it?

I have a brand new bit for no purpose other than the precise drilling here, and still I yearn for a drill press every time.

[drteming]

The pilot hole from the soldering iron is key, so is the brand new titanium nitride coated bit.  The combination of low speed and a very sharp bit makes drilling through plastic relatively easy.  I did not apply pressure as I turned the handle, letting the weight of the instrument do the work.  I also got pretty steady hands, though.

[fohat.digs]

Sweet.

I have now done several of these, and have gotten to the point where I can get 40 of the 50 holes nearly perfect, 5 are barely OK, a couple are marginally acceptable, and a couple are blown completely.

The definition of blowing - being that the holes -work- to put bolts through, but the hole is not perfectly cylindrical and at least one of the positioning crescents is hopelessly wrecked.

As for bits, I shopped around my local hardware stores, and bought what seemed to be the best of the 3 or so choices that were readily available.

[chicken charlie]

Just completed this, pressed a few keys and it didn't seem as crisp as I would have thought.  Plugged it in, it didn't work.  Then I read the Wikis again and realized some rivet stubs surrounding the bolts were keeping the springs from making contact with the steel plate.  Derp.

[o2dazone]

Just completed this, pressed a few keys and it didn't seem as crisp as I would have thought.  Plugged it in, it didn't work.  Then I read the Wikis again and realized some rivet stubs surrounding the bolts were keeping the springs from making contact with the steel plate.  Derp.

I noticed this makes a big effect on keyfeel. If your posts are not filed down, they stick out and not only make the board terribly difficult to assemble, but they also reduce how much 'sproingyness' the springs have when you've got more space between the barrel plate and the steel plate. I know the tutorial mentions not to bother with filing those down, but if you only have a couple millimeters exposed of the bolt, you might want to consider filing it down slightly. At least file it to where it's in line with the crescents. They don't need to be lower than that.

[fohat.digs]

I would be very careful "filing to where it's in line with the crescents"

The crescents are important to spacing / alignment. I use my chisel blade X-acto (good sharp fresh blade) with both hands to "top" or "shave" them clean and flat, like a mesa, but stay up a bit higher if you can. Filing or sanding is more dangerous and inexact.

Remember, these "posts" are the remnants of the shafts of the rivets, so they actually can, and should, go into, and through, the holes in the metal plate, anyway, provided that they are cylindrical and small, with no "mushroom heads" or burrs. That is where they were all along. If they do not mate up with their original holes, your alignment is off somehow.

[o2dazone]

yeah, I say that with the idea that people not to **** the crescents up. I actually had to read that part in another DIY, as it wasn't listed in this one. I didn't have too much of an issue filing them down with the same drill I use to run holes through the posts. But I definitely wanted the steel plate to rest against the crescents when everything is tightened down, without them resting on the posts. I'm not sure if that had any effect, but a couple mushroom headed posts kept my board from feeling 100%, so I tore it all down, and brought the posts down to at least inline with the crescents, and it felt awesome.

[chicken charlie]

Thanks guys.  I chiseled and sanded some of the debris and stubs down enough to level things out and now it feels like a NIB Lexmark-made Model M I got on Ebay, just less hollow-sounding.  Great stuff.  The board I modded was a grey label bought as "refurbished" with broken springs replaced (I guess they were twisted in and out if anything) and almost all of the rivets intact but it was still significantly worse than with brand new Unicomp springs and hammers.

[fohat.digs]

My top-shelf A-#1 Model M is a 1986 1390131 with a set of 2010 Unicomp springs (thanks, Demik) and a set of keycaps from a 1991 black label that were practically new.

The bolt-modding was done with care and the barrel plate (beige, sacrilege, I know) came from the same 1991 black label because the original had developed a couple of longitudinal cracks mainly on the numpad side.

I used tapping screws, not bolts, at the front (spacebar) side because the ribs prevent nuts from seating properly.

The biggest thing that I have learned is that the bolts should be just barely snug, but not tight. I hold the socket in my fingers (no handle) and twist "finger-tight" but not really very hard (remember, I am a big strong guy).

Although these things are sturdy enough to be weapons, as most commentators are all too happy to report, any and all of these parts can flex, even a curved metal plate, and any extra stress affects key feel.

My advice, at the end of a bolt-mod, is to tighten your bolts "just barely" finger-tight, no more, and then adjust slowly from there as you feel the urge.

You have a lot of flexibility for adjustment, cleaning, and repair after a bolt-mod. Take advantage of it.

[o2dazone]

Your DIY does a great job of explaining that the posts should be flat and how it affects key feel. But it doesn't cover anything about preserving the crescents, which judging from the previous tutorial, seemed REALLY important.

[chicken charlie]

Finished a Spacesaver.  Using a scratch awl like jpc suggested in his wiki does wonders for guiding the drill bit.  It seemed stiffer than the gray label I modded (though I didn't futz most of the drilling this time) so I tried the minimum number of nuts in Ripster's wiki and the sound is slightly more pronounced and the feel is less stiff.  I'm guessing it's impossible to get it as pingy as a Lexmark Model M because of the differences in the weight of the steel plate?

[fohat.digs]

A good sharp scratch awl is good but a sharp pointed soldering iron is better. Just be sure you are wearing your reading glasses (even you 20-somethings should buy a pair) and center it well.

Using less than a full compliment of bolts might be OK if you are lazy (or only have a few bolts, but since McMaster-Carr sells them by the 100 pack, so you should always have enough to do 2), but I recommend that you spend a few more minutes and do all 50.

If you want to adjust the feel, do it by making all 50 looser, rather than some fraction of that number tighter.

And, to dispute a much earlier post, I recommend that you start bolting and tightening at the center and spiral outward, leaving the outside corners for last.

[o2dazone]

That was actually my bad, I had punched a hole and drove a bolt through where there was no hole on the steel plate. So because of this, I had a huge bulge between the steel plate and the barrel plate, making it impossible to get some nuts on the bolts without squeezing very hard, and working intricately from the outside in. When I tore it down, and did my work better a second time, and didn't have that bolt there, it came together just fine. I actually just started left and went across the board. Is there a preferred method?

[o2dazone]

Now I have (well..had) an original Model M in pretty decent condition. Was missing about 10 rivets. It had a very sproingy and clean feel to it. When I bolt modded my SSK, and put in brand new springs/hammers from Unicomp, it didn't feel quite like the original. I thought the bolt was supposed to bring it back to that original feel. Or is that feeling a one time thing for these keyboards, and once you tear them down, you never get that feeling back? I know that the weight of Unicomp springs/hammers should be SLIGHTLY less than original parts, but it's not just the weight, but the key feel feeling different. When I bolt modded my second Model M, the key feel was retained. I'm wondering if I just did a cleaner bolt mod on the second one, or if Unicomp does have a drastically different feeling key feel swapping their new parts into old keyboards.

[chicken charlie]

That's one conundrumel.  I only have a new Lexmark as a benchmark and no matter how many bolts I loosened or left off I couldn't get the feel and sound exactly the same on a grey label.  I thought that was because of the guts (steel plate differences) but it sounds like there's lots of variables that go into this mod.  I put Unicomp parts into a fullsize and spacesaver and they're just about similar for what it's worth, and I futzed the fullsize with lots of delirium tremens drilling.

[kywirelessguy]

Tad late, but this combination achieves the same thing as the Dremel but at much lower speeds.

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This Hitachi cordless screwdriver also has a torque setting, so if you use screws in your mod there is no risk of over-tightening.

The torque setting could help with the bolt version too if you had the right size nut driver.

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[kywirelessguy]

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$44.00

I bet you could build a DIY version on the cheap.

[kywirelessguy]

I have about 1,000 wheelwriter barrel plates so even if I Michael J. Fox one or two I'll be ok.

If only they were compatible with model M's...