Still looking for help on the Challenge 15 mpc press

We are still looking for anyone who might give us some advice pertinent to the mpC, as opposed to the ma and mp. We are still having problems with our carriage return, the motor labors and subsequently blows a fuse.
We bought the press through briar press, from someone in California. She was able to operate it, and I have attached a video of the actual press in action at her end. The press has three switches on the control panel. As far as we know, the left switch operates the power inking. The middle switch turns on the light, and also operates the carriage, toggling it to the right moves the carriage to the right. Toggling it to the left should move the carriage to the left. The same is true for the switch to the right. However, each time we try to return the carriage to the left, it makes the motor labor and blows a fuse. We replaced the fuse with a breaker box, since the fuses are $8 a pop, so we can experiment without replacing fuses. We attached the manual handle so we could move the carriage. Two issues are apparent. One, the carriage is stiff, but not so stiff that the carriage won’t move to the right. Second, it seems redundant that both the middle small white toggle switch and the right switch, a larger toggle switch would do the same thing. We did have to replace the main wire when we got it; the insulation on the wire was disintegrating and was too dangerous to even plug into test the press when we received it.
Any suggestions would be appreciated, and if anyone knows someone who has a challenge 15 mpC, I’d love to contact them.

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oops, couldn’t post the video …here is a diagram of the control panel

image: challengecontrolpanel.jpg

I would suggest that you start by disconnecting the middle switch, taping off the wire ends to prevent contact with anything. Then try the press again. It seems to me like one possibility is that if the two switches are connected in parallel one is shorting the other, or attempting to apply power in the opposite direction, when the position of one is changed. I can see no reason to have two switches doing the same thing. Perhaps the middle switch is meant to be the main “power on” switch, thus the lighted emblem as an indicator of power.

This diagram shows how I would guess the wiring of the press should be connected, though I do not know the press and this is just a guess.

The center switch could be wired to switch power to both the inking system and the carriage in one side, and just the carriage in the other side, with the light energized in both positions.


image: press wire diagram.jpg

press wire diagram.jpg

would it be crazee to suggest you double check the press is absolutely level in both axis in case the frame is twisted a bit which causes binding?

As You seem to have had some success in examining the wiring, inc replacing Your Mains input, would it be possible to produce a Schematic diagram of the existing wiring and its routes etc. at the back of the Panel, (obverse) from your front view schematic.?.

Inc.any colour coded wires, actual route(s), point of origin(s), point of termination to which switch(s), or block of connectors, or Relays,! etc.etc.

The reason for these suggestions being, IF You can post more Clues, however sparse,? and taking A.L.P.s (Bobs) schematic into account, (and more yet to come, Hopefully) the *Puzzle* may become easier to solve.???
Good Luck.

Good news for us! Ralph Reed (our new letterpress guy and a genius too) came to the BARN and repaired the letterpress. Turns out the problem was that a part had been damaged during shipping and it was keeping the auto carriage from working. We still disconnected it (a painful decision on my part) even though it could work, because we are a community studio and it was a safety hazard (no safeguards). So mystery solved…