Base or bearing problem?

I’ve been experiencing some crazy inking problems, allow me to explain the situation.
Equipment: Brand new rollers & roller assemblies, boxcar base and a challenge 15mp

After setting the rollers, when I put the base with the plate on it back on the bed, the rollers only ink the first 4” or so of the plate. It looks like the issue may move around with the base. The 2nd photo shows the same plate, flipped around with the base slid down the bed about 2.5”.

I don’t see or feel any irregularities in the cylinder bearers so I’m only left with blaming the bearing settings. I’ve set the bearings according to this article by Gerald:
http://vandercookpress.info/vanderblog/literature/articles/lange-adj/

Please offer your help on resolving this problem.

Thank you kindly.

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Outside of any press parts or maintenence issues you may be encountering-

Have you also tried flipping you base around 180 degrees, or even upside down, or making sure there is nothing lifting one side of it (loose paper dust or some-such element you may not have noticed)?

Assuming you’re technically proficient/competent with your press- Have you tried lowering the inking rollers below the normal setting to determine if the problem is related to the rollers or the base? (I am not technically proficient with your press, but I think there is probably an inking roller adjustment for height?)

One more thought- have you tried unlocking your base entirely to check the inking? You should do this first and make sure that the Quoins aren’t over-tightened and somehow lifting the base.

I don’t know about the Challenge 15mp but the Reprex knock off of the Vendercook has a mechanism built in to the concentric gear that throw the press off impression when the type matter or material to be printed is too high. I have read that it was to protect the cylinder from damage.

Might the Challenge have something similar? Our press does something very similar to what you pictured. It inks part way down then inks the rest much lighter.

Daniel:
Have you tried the roller gauge in various areas down the length of the bed? If so, do you notice variation in the ink stripe or pull of the gauge as you move the rollers further down the bed? Is the roller gear track clean? a bit of dried ink or grunge in the gear track can raise the rollers up a bit.

If all that checks out, then the base must be lifted on the feed end a bit. Could be something under the base lifting it up on one end or could as Haven suggests, be the tightening of the base raising it up just a bit. If the piece of furniture is beat up a bit, it may not be quite square with the bed and would lift whatever it was locked against.

You might try just setting the base in the middle of the bed and see if it inks OK.

It is a lot easier to be there, but you’ll get it figured out.

John Henry

wish you guys were in san diego.

I put a piece of tin foil under the base, on the end of the bed side. It helped with the inking a bit but I can tell that the impression is a bit deeper. That suggests that the base is ok but the rollers are changing height as the carriage moves down the rails?

Your two photos point more toward inker adjustment , assuming that your chase is not twisting because your quoins are over tight . As suggested try a careful pull with the base “loose ” in the bed ,this is safe enough with a hand wound press , not recommended for a motorized cylinder .

You should also check roller settings on and off impression. If the bearings are set incorrectly on SP-style presses, the carriage will shift and roller height can change.

Daniel, I just went through this exact problem with my SP-20. I had my carriage bearers adjusted as well as replaced two broken trip springs. I think the broken springs were allowing the carriage to rock ever so slightly into trip mode. In checking with the roller gauge, I found the rollers raised at exactly the same place. Check that for yourself and see if it’s the same thing.

jonsel, the carriage bearing adjustments are exact and affect both impression and inking. The trip springs may be more vague in their effects, but springs usually go one at a time, so you will see differerences side-to-side. Proper lubrication is a factor and may affect how the cylinder eccentrics behave. (Some SP owners don’t notice the tiny notch and dab of paint that indicates the lubrication point for the cylinder eccentrics, or may have tightened the setcrews on the cheek pllate, which impedes the mechanism). The movement of this mechanism also depends on the nylon wheels, which wear and may have their own eccentric adjustments.(Of all the SPs I’ve examined, I only had to check these posts on an SP-25, and the adjustble posts were definitely eccentric; don’t know about the rest).

Thank you guys for the great info.

Jhenry
The gear track is free and clear. The roller gauge is pulling a pretty consistent stripe across the bed. Would setting the rollers in print or trip make a difference?

Can anyone confirm longdaypress’ notion of the impression throw off?

The base I have very lightly held in, since its a flatbed press I don’t need to over crank the quoins (and have also become callused to lockups that would not stand a chance in a platen press).

Jonsel
I am encouraged that you solved this with your sp20 but it seems that my trip springs are in working condition. Did you adjust the bearings or have it done by a press mechanic?

Anybody have a tried as true method of setting the bearings? I’m getting even impression side to side and it rolls down the bed smoothly. But it seems the rollers lift once the bottom bearings become engaged.

On SP-type presses the bottom bearings hold the cylinder carriage against the rails on impression stroke, preventing bear-off. The top bearings support the carriage while off impression. Since the rollers are attached to the carriage, you can’t get consistant inking unless the bottom and top bearings are each correctly adjusted and balanced regarding each other. You could still have each correct against a feeler gauge and not correct over all. That’s when rollers shift between on- and off-impression positions.
This is going to be a long trial-and-error process for you. It is totally undocumented, but real. Start with getting the impression bearings right, then adjust the carriage bearings until the roller stripes are identical at both on and off impression.
I hope your press isn’t against the wall. You can’t do this without real working space on either side of the press.

I had a press mechanic do the adjustments. I’m not that mechanically inclined and didn’t want to screw it up worse than it already was!

You said you’re getting a consistent ink stripe on your gauge across the bed. Have you checked front, middle and end of the bed as well? If it’s lifting in the exact same place, it sounds like the bearers need to be adjusted again. If I recall correctly, my mechanic (Perry Tymeson) said the carriage could rock, ever so slightly, if the bearers weren’t set right. Since the rollers are part of the carriage assembly, that would affect them.

I know I’ve read many threads and peoples explanations of how to set the bearings but I’d really appreciate if someone would list step by step how this process works. A private message or phone call would be a life saver.

One thing that seems to be messing with my bearing settings is the under side of the rail. Right after the ink drum there is a slight drop in the rail, and this is where the back bearing engages, therefore lifting my rollers.

Have you tried to reach out to Paul Moxon, head of vandercookpress.info? He may know a good mechanic out in your area who could come help. I’m always of the mind that it’s nice to try to resolve some things myself, but there are areas that I’d just rather hire someone and get it done once and for all.

You might also want to post this same topic to the Vandercook page and see if you get some additional advice.

I think I’m getting close. What I’ve noticed is that when I loosen both of the bolts that hold the bearing in place, the larger one that the bearing is actually attached to sags slightly, so if I set the top bolt to where the tension and spacing to the rail is good, once I lock it all down it’s too tight. It seems like I need to set it too loose then tighten it. Check & repeat.

Danielheff, you may have answered your own question!! Following, not facts just ideas, if as one suspects your press follows the same format as ones we see here, your upper (presumably) “eccentric” ink train and imp. cylinder bearings have the advantage of the train weight (of the carriage) keeping them in firm contact when adjusting and locking up!!! If (big if) the very second you slack off your bottom locking nuts gravity takes your bearings out of contact, consequently with all the will in the world you retighten (probably via a worn screwrdriver slot) to an acceptable degree of contact, the second you tweek the locking nut, you (possibly) loose just a minute degree of contact, when amplified through 2/3/4 other contact points in the whole train, is it possible that with just say .002 thou slack to begin with, in your original adjustment, and with the inevitable tiny rise on your impression train, you actually end up with, even thin stock, taking you out of 100% impression and/or inking capacity??? Preceeding ONLY Ideas>>>But one I can quote as fact, (of course from the Monotype) on that machine there is one set of adjustments (six in total!!) whereby it is done “by the book” but invariably ends up, having to be done again and again, because every thing is adjusted and locked up perfectly, but because of the minutest wear in the whole train .025 thou is not unusual for out of truth??? “O S***E start again!!>>> Following ideas not facts.>>> In Essence (POSSIBLY) same syndrome on Proof press. Maybe Chat up your local Auto Mechanic or Motor Engineer and ask them how they use Feeler guages to achieve these kind of clearances, down to .001 thou. maybe, and apply to printing press!!!

Daniel; just an additional thought and thing you could check before proceeding with (even more) variable testing- but have you leveled the press itself out very well end to end?

I know, stupid question, but hey- not every press STAYS level once it’s ‘leveled’ the first time.

Danielheff

The instruction and parts manual for both models 15MA and 15MP contains instruction for adjusting the impression cylinder. Variance in presses due to wear will require some experimentation to achieve the desired results. You are aiming for full coverage over the length of the bed. This might require some sacrifice of minimal coverage at the head and tail of the bed.

If you do not have the manual one can be downloaded from the Vandercook.com site.

Gerald
http://BielerPress.blogspot.com

Gerald-
I don’t think the vandercook.com site will have the manual. I think you’re meaning vandercookpress.info ?

http://vandercookpress.info/

Unfortunately still haven’t solved this issue. Does anyone know a tried and true method that will help me out?

The instructions in the manual are extremely brief.

My inking is now consistent when in “trip” mode, still no luck with print mode. So to keep up with work I’ve had to put in trip, ink the form. come back to the feed board, raise the rollers. Print & repeat. This has doubled the time to print, anybody know what this suggests?