Uni I Drive Gear and Roller Height Adjustment

I have a Uni 1 manufactured in the 60s, still being cleaned but also being used to print. I have two observations/questions which I welcome help on…

1. The drive gear (if that is the correct term) oscillates when the press runs and the rollers are engaged. A woodruff key was missing and replaced but do these gears go out of true over the years? It seems true on a flat on the surface (using a steel rule) but I suspect that the large hole in center of the gear is not “square” as it should be.

2. Using the black knobs to adjust the roller height is interesting. With the knobs all the way up (turned counter clockwise) so there is no height added to the rollers, things seem to print quite well. And, if I begin to turn counterclockwise, things get bound up along that drive gear – not good. No horrible sounds of crunching or anything, but is the adjustment of height using these knobs that gross a process or should a small turn of the black knob make a significant difference? Sometimes I wonder if my rollers are seated properly, but if they were not, then I would expect not to get much good printing.

Any advice or help is greatly appreciated. Best – Neil

Uni I Drive Gear and Roller Height Adjustment

6 thoughts on “Uni I Drive Gear and Roller Height Adjustment

  • August 29, 2013 at 2:34 pm
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    Thanks Eric. Neil

  • August 29, 2013 at 2:02 pm
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    I’d say it is normal for some sound as the gear passes over starting tooth and onto the gear rack.
    The Allen screw inside the end screw locks the mechanism into place. Without it the rotation of the rollers can loosen the end screw on the gear side and actually walk it out until it jams against the carriage.

  • August 29, 2013 at 11:40 am
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    Eric and all – I switched rollers and attached the gear, insured it was aligned with the track and still oscillating and the slightest bit of crunching when it passes over the transition part of the track. What is the purpose of the Allen screw down the center of the end screw? Time for a new gear? Neil

  • August 29, 2013 at 10:22 am
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    You also need an Allen screw to loosen the setscrew down the center of the end screw.
    IF the gear got damaged from slippage while used without key in place, then the core would also show damage. The front roller should also have the flats and keyway, you could swap rollers and gear and see if the situation improves. The gear may cause problems if you do not have it correctly aligned, directly over the gear rack.

  • August 29, 2013 at 9:46 am
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    Thank you Paul
    1. There is not noticeable play but the gear does wobble very slightly when it moves down the track.If there is such wobble down the track and surely when at rest before engaged with the track, do you suggest replacing it?
    2. I’ll check all. BTW, is a simple very side flat head screwdriver used to remove the end screw from the bearings? Thanks again. Neil

  • August 29, 2013 at 9:28 am
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    1) The gear bore (hole)can be, and often is, reamed. Is there noticeable play after the set screw is tightened? Does the gear appear to wobble as is travels the rack?

    2) It’s always a good idea to check that the the bearings are seated on Universals and the SP20 and SP25. Also the bracket rests for the adjusting screws should be flat—not bent or dented.Lastly, be sure to loosen the hex head locks screws on the side of the bearing block before turning the black knob and tighten afterward. If the flat bar wrench (OEM) is not present, use a 1/4″ open wrench. If the locks a stripped, order new ones from NA Graphics. Socket head cap screws (8-32 x 1/2″)available in any hardware can be substituted, but are not as convenient. The thick hex head makes this screw a specialty fastener.

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