Looking for advice. Part 1: Uni III(ab) form roller tilted

I have recently begun to produce work on my Uni III after a long hiatus, and have run into a couple of vexing issues.

Firstly, I realized that the rear form roller was laying down ink only on the side opposite from operator. The roller will not adjust low enough on the operator side (the knob and assembly just rocks back and forth once the gear is on the rack) to ink a form. When I got the press I noticed stacks of two 2pt leads had been used to shim the form roller gear rack along its entire length (photo). As I am a complete neophyte I just assumed that this had become necessary to keep the rack level at some point. Now I’m thinking that the leads are forcing the gear too high and angling the roller. If this is the cause I can certainly pull the leads out and “see what happens” but if they are necessary evil I’m not sure what to do to keep the rack height both consistent and also low enough. I have plenty of 1 pt nylon leads I could cut into shims for instance.

Any thoughts would be greatly appreciated!

Looking for advice. Part 1: Uni III(ab) form roller tilted

4 thoughts on “Looking for advice. Part 1: Uni III(ab) form roller tilted

  • January 23, 2018 at 9:20 pm
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    Thank you again Paul for going over this with me.

    I temporarily plugged the worn spot on the bearer block with some brass.

    The leads we so gunked in there I just lifted the whole rack out (with care) as there was a fair amount of grime caked in the gaps between the leads. The original shims are gone but have been replaced by long runners of thin steel punched to accommodate the screws (I left these). I used a galley and some .002 paper as suggested to get a before and after shim removal with the roller gauge (hadn’t even occurred to me to do this). The roller “just barely” makes contact on the operators side which is an improvement but still imbalanced.

    Leafing through the manual and your book it seems the form roller gear for the Universals should be 3in diameter? I measured the one on mine and it is in fact 3 1/7in. Could that be it?

    The blocks and the adjustment posts are pretty worn on both rollers on the far side in contrast with the operators side which strikes me as odd. I wonder if I should just try and scrounge up some replacements? I l already have to reach out to Fritz to try and get some sheet fingers and a star wheel I’m sadly missing.

    I really appreciate this, I am really focused on getting the kinks worked out.

  • January 23, 2018 at 2:44 pm
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    Let’s start over: Remove these leads and see what you get. (Original shims, when present, are plastic. These leads are someone’s fix to compensate for a printing form or rollers out of spec.)

    0.970 – 0.918 is 0.050. Place a galley (0.050) plus a sheet of phonebook paper (0.002) beneath, in the bed and use the 0.918 rollers setting gauge. Or you could buy a 0.968 roller setting gauge placed in the bed on a sheet of phone book.

  • January 23, 2018 at 8:06 am
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    Thanks very much!

    There is indeed quite a deep divot on the bearing block on the far side of the form roller. Can the blocks be removed and perhaps flipped individually? If not, I can plug the worn area.

    Also the roller is 2.98 inches across the entire length. The form rollers were replaced about 5 years ago but have been idle for a while so maybe it shrunk in that time.

    I have been printing mostly sintra-cuts and have had to lower the bed consistently because the sintra plus the aluminum base I made are over type high (.970). This makes adjusting the rollers difficult for me as I can’t use a lollipop there and lack the experience in determining if I’m over/under on ink without chasing it back and forth over many test prints. That is one reason it took me a long time to realize that the back roller was only laying ink down on one side.

    As for the shims, I confess I am a little bit confused. The un-modified shims aren’t typically strips of leads stacked up are they? I’ve worked with Universals before that had no visible shims under the rack maybe those were not right?

    So if I understand correctly I would need to lift the bed up some (reduce packing to compensate) in order for the operator side end of the roller to be able to lay ink at all, as there is no way to set the roller any lower (save replacing the roller to get an additional .02in)

    I appreciate all the help.

  • January 22, 2018 at 8:01 am
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    Keep the shims in place. It’s possible but unlikely that they have been modified.
    Measure the diameter of the rollers, they should be 3″ and are probably flared on the ends.
    There may be excessive wear on top of the bearing support block that contacts the bottom of the form roller adusting posts. These blocks are pinned a bolted to the carriage side plates but can be rotated or repaired

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