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IBM Model 29 Keypunch Station

CuriousMarc is on the game and while I was expecting scans in a few months he got them digitized in a week. Seriously dude you are a busy person and thank you for going out of your routine to help me out. :)

So after analyzing the model C schematics I found that indeed some of the wiring differs from the Model B which is what was confusing me so much because so many of the undisturbed wiring was going places that didn't add up. The wire that comes from TB32-1 according to the schematics routes to relay point 17-1 Common and shared the 2-socket terminal with a jumper to 17-5 NO.
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The other wire however was a challenge because to the wiring diagram 26-8 NC doesn't go anywhere besides 26-9 and 26-10. It also was such a complicated circuit it was separated between pages.
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This entire circuit seemed to be fed 48V from the PSU however there was no continuity where I expected 48V to be so the wire could only be the 48V line. Sure enough digging further I found that DC power is distributed in series to everything via multiple strings and in this string I could now follow continuity up until 14-1 Common, so that had to be where the wire went.
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Well that cleans up the wiring. Now the relays.....
 
Progress of cleaning the relays over the last has consisted of:

1) Pull all the wire contacts from a relay and soak them in deoxit
2) Using 1500 grit paper soaked in deoxit, clean the contacts
3) Using another sheet of 1500 grit, clean each wire
4) Reinstall each wire contact. Test to make sure contacts are now clean
5) Smoke cigarette, contemplate your mortality because there's still a dozen more relays to go
6) Continue onto the next relay

This is a brutally tedious and time consuming job compared to the contacts in the punch mechanism itself. :p
 
Okay.
That was brutal.
It took several weeks on and off but ALL of the relays have been dismantled and cleaned.

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This completes cleaning and repairs on the relay frame. Now I can go back to focusing on polishing the metal.
 
Polishing is now complete. A clean and unpunched card will now pass through without jamming, snagging or getting damaged other than getting two black stripes from somewhere in the feed picker. Might of gotten something too oily.

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For the moment I have not touched them. They still got a nasty divot in them and you get a "click-click-click" every time you cycle the clutch but cards still feed through without much fuss.
 
Well April is a few days away and this week looks to start the last leg of the Spring Thaw as we come into the teens again.
The keypunch remained outside for the entire winter however was bagged, blanket wrapped and strapped so it got cold but was kept dry. I never got any time to work on the keyboard. I have not been able to source additional parts or trades for the correct keyboard so for now I may still be stuck with a hidden switch for the punch/interpret function.
The initial inspection seems it's looking good. The next step is to begin cleaning of all the contacts in the machine.

I would love to know if anyone has a better method to cleaning the contact and wires beyond the 1500 grit above, deoxit and holding the contacts shut as you pull a strip through. I've had complaints about that. (and I understand it's not the best way to burnish)
 
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