About to embark on cylinder carriage adjustment-Universal III AB

The symptom: The top of the bed has less impression. At first I thought maybe the adjustable bed could be at fault, but a level revealed it pretty even from top to bottom center, but the operator side corner top appears to actually rise, in complete contradiction to my problem of less impression at the top in general. (toward the cylinder)
A roller gauge inking test shows that in trip there is no line when it is placed at the top, and at only about 8 inches from the the top does it show a good stripe. So it would seems that the bearers traveling over the bed are the problem.
There does not appear to be any wear or metal shavings on the rails and they are clean and oiled.
So am I right that this is what needs to be done? I’m about to start a project and I really would like to solve this once and for all. How does the eccentric adjustment improve an impression variance in travel? Or is it the bearings needing replacing…

I will do the test for impression-after getting my form out of the way.
Got none of those feeler gauges, though David says you can get a kit of them, they are just not as long as the ones Paul showed us. Or use paper.
Any tips/reminders appreciated!

About to embark on cylinder carriage adjustment-Universal III AB

5 thoughts on “About to embark on cylinder carriage adjustment-Universal III AB

  • June 20, 2014 at 7:38 pm
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    I cleaned up the form rollers today, but saying they are actually clean is another thing. This press was in a college setting before it came to me and I had never seen any clean metal on the roller gear. So much ink buildup it’s going to take me more time if I want it all gone. The hex nuts are there for the lock screw, just really gummed up. The L brackets are a little loose, but I don’t see how to tighten the smooth screw head. I used a small tool to pry out ink buildup from the adjustment slot controlled by the knob. Mostly used mineral spirits toothbrush and green scrub pad to clean.
    After I did some adjustments of the height, I confirmed that I could get no better than a stripe 5 inches from the top and no closer. That is just too much print area to lose. Tomorrow I will test the impression with brass rule.

  • June 20, 2014 at 9:44 am
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    Found my notes from Paul’s Workshop! Yay! Apparently I take pretty good notes for a hearing aid wearer. (not just for show) Going to take a look at the form rollers today and see what I can see.

  • June 19, 2014 at 6:17 pm
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    I should mention that I have adjusted the rollers by turning the knobs only.

  • June 19, 2014 at 6:15 pm
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    Thanks Eric, for more information. I wanted to check out whether my roller gauge test was the same on print and trip, since if they were ideally the same, I would not have to adjust the cylinder carriage. I made a chart testing over the bed with back and front rollers on both print and trip. Print has less inking, with narrower stripes, but the main problem of less impression towards the top is still there, with no ink stripe at all appearing at the top of the bed. 
    I have also read about the form rollers needing to check out. Seems like I should do that first. I read some instructions for raising and lowering them that talk about loosening a set or end screw before adjusting the knobs, which I’d never heard of. Such a basic thing I have missed entirely. Where would that be? So I’m not sure if my rollers are at all acting right. In my test I do have the correct width on trip in many of the spots for the front roller, though.
    I’m putting the chart here for anyone who wants to take a look. X means no stripe, and check is a stripe. The top of the bed is to the left, just as seen from operating view.

  • June 19, 2014 at 11:39 am
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    I would suggest that carriage adjustment and impression adjustment are two different things, at least on Universals and SPs and 4s. Impression is just the cylinder and bed bearers being held together with minimum pressure needed to prevent bear-off, and on this model is the bearings that are adjusted against the upper rail. Adjustment of the whole carriaqe affects the difference of roller height between trip and print, and here would be the adjustment of bearings against the lower rail. In both cases the bearings should be adjusted so the carriage is level and not tipped. When correct, rollers will be at same height on both trip and print. Very fussy work.
    Add an adjustable bed and there are more variables. I hope those who have tried to reset AB models will chime in.

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