I have a question about a Universal I hand press. The problem first became noticeable after setting the rollers to the correct height and printing for a while. The back inking roller gear will sometimes jump off the track when in print mode and make a terrible sound. We were able to replicate the problem by raising the roller by the gear and ‘printing’ with no ink on the press. There seems to be some wear on the track by the gear because of this problem. How do you think this could be fixed? Maybe the rollers, because of vibration, change height? Or can the rollers swell and cause this problem? The serial number on the press is 25748.
Post Details
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Post Title: Universal I gear and rack wear
Author: Martha Chiplis
Filed As: Form rollers/gears, Universal series
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9 comments have been posted on “Universal I gear and rack wear”.
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Yes, by ‘worn’ I meant the teeth on the one gear are not as pointed.
Note that the roller gear has shaped teeth on it–that is each tooth is pointed– by design and this is often interpreted as wear.
So I tried the rollers from the other Uni 1 and they worked well. No problem there. The gear on them is also not worn down- I did a visual comparison with the problematic one and there is a definite difference. Looks like we will use the rollers from the other Uni 1 for now (it isn’t set up for printing yet) until we can afford new rollers.
Thank you again, you all were much help.
Thank you again everyone. There is another Uni 1 in the shop now, and it just occurred to me that we can try the rollers from it on the problematic Uni 1 and settle the issue once and for all. I hope to be able to try that later today.
Eric,
I am pretty sure those springs were only on some SP=15s. Many I have seen do not have the posts for them or even a hole in the side plate where it would have been.
I’d guess that Martha’s suspicion is probably correct, but your point about rack shims should also be investigated.
Daniel Morris
The Arm Letterpress
Brooklyn, NY
If the rollers are correct diameter, maybe the shims under the gear rack have been removed or changed. At the factory the rack was underlaid with plastic shim stock to get it to the correct level to mesh teeth properly with the roller gear.
Also, I’m not sure about Universals, but some Vandercook models (SPs, & ?) have a spring-tensioned flap to hold the geared roller down against the rack, and the springs do get lost. In that case there’d be a couple studs with grooves to hold springs between them.
Thank you both. We did check the starting tooth and it seems to be fine. The gear will be checked for looseness. The suspicion is that the rollers are swollen and so are set too high.
Does the gear mesh properly at the begginning of the gear rack, but go off along the way? Or does it happen at the beginning?
If early, check the starting tooth. It is that short, articulated gear segment with the spring under it. It should catch the roller gear and get it in time with the gear rack. But sometimes the springs are missing, sometimes the starting tooth is badly worn. The teeth ARE much sharper than the teeth on the gear rack though.
As Paul says, a loose gear can cause problems, and also check the locking allen screw in the end of the roller, that locks in the retaining screw holding in the roller bearing.
Possible reasons for that terrible sound: 1) The rollers are set too high, maybe they have swelled. This would cause the gear to skip along the top of the rack. 2) The set screws on the gear is loose. This would allow the roller core to rotate (or slide) over the form independently of the gear. The hole on the gear may be reamed out causing it to wobble as it rolls over the rack. As a temporary fix, wrap Teflon tape (white plummer’s tape) around the core to fill the gap. Then order a replacement gear.