Major inking issues… in middle of job, please help!

Before you alter anything drastic ,as you have been ok up to now , lift your ink platter out (disc) and hav a good old clean up in the recess it lays in and try a gain . I say this because that pattern on the edge of the disc i have had on my cropper ,Not exactly the same as mine has three discs within the large one bbut its not costly to check it out and you should do it periodically any way .

Change the tape on your rails, from the pictures it looks well worn and bunched in areas.

The kluge lady has a point i missed that , not familiar with bearers that are that worn you have to tape them ,although i have had treadles that used leather straps that you put the tape beneath if necessary !

Since you have a problem getting the rollers to ink evenly, and you have a problem getting the rollers to ink the type evenly, perhaps the rollers do not have an even surface (whether they are relatively new or not). Another reason I suspect this is that in your picture of the roller, there appears to be a mark on the roller an inch or two in from the truck. It looks like this might be the start of a flat spot. Put a straight edge, like a metal ruler, along the roller parallel to the roller core (shaft), and see if the surface is as straight as the ruler. Can you see light in some places between the ruler and the roller? Do this in several places around the rollers. (Have you ever left the rollers lying on their rubber surface when not in use, or left the press with the rollers up on the ink disc…….I hope not).

If the rollers are uneven, you might be able to put a sheet or two of paper behind the chase to get the low places on the rollers to ink the type. However, you still have to get the low places on the rollers to take ink from the ink disc. You said you “push a bit” at times. However, before you do this, be sure that you think through what you are doing from the safety point of view, and never do anything which is unsafe…..NEVER compromise safety. Also, NEVER wear rubber gloves around a moving press, even if you are moving it slowly by hand, because the rubber will pull your fingers or hands into a press, or into press parts, much more easily).

I’ll go with girl with a kluge, clean your rails and put new tape on it…

I would think it may also be worth removing the “trucks ” degrease everything including the rollers and have a go again !

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Thank you so much for your help everyone! I am going to take all the tape off the rails and start again, as I think that has to be part of the issue. Will try all of the other things suggested as well… hopefully will find the solution one way or the other! Will report back! thank you again for the assistance, it is so much appreciated.

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I’d also recommend NOT using electrical tape- that stuff gives too much and the adhesive is very fluid compared to other tapes- I’d go with artists tape or at least a good solid masking tape.

Hope you get to the bottom of it soon!

Try UHMW tape for the rails, here is a link on the NA Graphics site,
http://order.nagraph.com/cgi-sys/cgiwrap/nagraph/sc/productsearch.cgi?se...

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I don’t think this will solve your problem but another thing you should try to do if possible is to have your rollers roll perpendicular to the lines of type. That way they don’t tend to ride up when they are over type and then drop into the valley between lines of type.

I agree that electrical tape is bad. I like using packing tape.

Also it may be that your rollers are just not at the right height and are barely hitting the type and then any unevenness will move around a bit. Setting the roller height is something that needs to be done VERY carefully.

If the problem tends to be toward one side of the print take some tape off that side and see if it helps.

Also looking back at your first photo, are the rails as rough as they look like they are? If so, that would surely create lots of problems. Also you don’t show the trucks that ride along the rails. If you combine beat up trucks (expansion ones perhaps) with the rough rails you could get lots of variation.

You say that you get 10 bad prints for every good 6. Is that ratio consistent? 6 good…10 bad… 6 good?

If it is indeed consistent, a check could be to somehow mark the position of the ink disc at the beginning of the pattern and see if the pattern corresponds to that position of the ink disk coming back around again.

I’d imagine if your ink disk has a slightly concave warp to it, it wouldn’t keep the ink from getting distributed, as the rollers might have contact when rolling perpendicular to the warp, but not when it approaches it head on thus not picking up ink for the plate.

It is a good point (lead grafitti) that running parallel with inkers can be troublesome ,not certain its the case here but to avoid that problem on a hand fed machine is to lock up the form on a slant and put yor sheet stops on the packing on a slant too this helps in some inking troubles .
It is probably oily patch on rollers/Forme or the manky rails, inking trouble is one result of many silly things its purely an elimination process ,patience will get you there in the end.

I’m generally not in favor of applying solutions until one has correctly identified the true problem. I would do a bit more troubleshooting to be sure before you go through the trouble of re-taping your rails.

Given the amount of punch in the paper it clearly isn’t a packing issue.

Try this first before redoing the rail tape and using your gauge to set the roller height:

Pull the form from the press. Put a sheet of office bond 20# paper behind it and secure lightly to the edge of the chase with a bit of scotch tape so that it doesn’t move when you put the form back in the press. Remove equivalent packing from the tympan to compensate and run a few impressions. Did the problem go away? If so, it is your roller height and rail tape. If it didn’t then it is something else.

Inking problems are either:

1. pressure/packing/makeready
2. uneven form or “wobbly chase”
3. roller height
4. ink problems (temperature, dryness, tack, etc…)
5. damaged or warped rollers
6. damaged ink plate

Not much else is involved and you should troubleshoot in that order since that is the order of severity to resolve from easiest to hardest.

FWIW,

Alan

All good ideas
We had this problem today when I was running some 8pt Wedding Script.
I had the rollers and the base so fine that after about 50 sheets I would have this problem.
It was only a run of 500 so I decided not to use the fountain.

All I had to do was add a smear more ink on the disk every 40 sheets or so and the problem went away.
Doug

BTW
The only tape we allow on the rails in our shop is painters blue tape or scotch tape all the others have too much ooze from the adhesive.

Also we often add scotch tape directly behind the plate, face down to the base (to make it easy to remove) it is more spot specific than adding it behind the base
Doug