Flood of color has a bar across it

Hi all,

I’ve been doing letterpress on the side for almost two years now- I still have a lot to learn!

I’m on a C&P 8x10 press, printing on crane’s 220 lb lettra.

I am currently printing some business cards with a flood of color on the back. I know it will print textured and “salty,” and that’s ok. However I’m getting this weird bar across the lower third of the print. I have tried compensating this by cutting out little pieces of tissue and thin paper, and putting them behind the tympan to no avail.

I’m not sure if something else is going on that I could check… Has anyone else had this problem? Does anyone have any suggestions? Any help would be appreciated!

Thank you,

Nikki Castiglione

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Log in to reply   8 replies so far

I’m guessing you are printing these with the sheet oriented vertically, and the dark stripe is appearing across the press from side to side.. The dark stripe has to do with the way the rollers are depositing ink on the plate, putting more ink on the plate where the dark area is. Are you printing with all 3 rollers? If not, that would help.

Since you are taking a lot of ink off the rollers for this job, they don’t seem to be able to replenish adequately between prints, except in the dark area. This is due to how the rollers are vertically spaced on the press. Have you tried double rolling the plate (letting the rollers ink the plate once (or even twice) with the impression off and then making a print.

If this job is not too big in size, another thing you could try is to lock up the plate up or down in the chase so that you avoid the area which is darker. Then at least the green block would be more consistent.

Hi Geoffrey,

Thank you for the reply! Yes, the sheet is oriented vertically with the stripe appearing across the press from side to side. I only have two rollers so I’m only using two. I have been double hitting the plate. I tried over-inking everything and that seems to help quite a bit, but there’s still a faint bar. I might just have to roll with it…

But you’re saying that if I flip my plate’s orientation it might be less noticeable? I might go out and try that first. At this point anything’s worth a try I guess.

Thanks again!

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Update… The more I press, the more it gets like the photos show. The dark part gets darker, making it more noticeable.

What do you think will be the best fix? A third roller?

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Replying to your 19:13 post, I’m saying that the dark place is probably always going to appear in the same place with respect to the platen. So, if you can move the plate up or down in the chase to avoid that place, you shouldn’t get it. (It will still potentially be there, but since the plate isn’t in that place to pick it up, it won’t be on the plate, and on the job).

I doubt if orienting the plate vertically will help….it may make it worse.

A third roller would be a step in the right direction. On my Golding Pearl with 2 rollers I always have trouble. (I used to have a C&P 8X12 like you have, but I had 3 rollers and it did a good job of inking).

I don’t think more ink is the answer, but a consistent layer of ink everywhere on the plate is what you need.

Try this just to see if it helps, not necessarily to produce the job this way: don’t put on more ink than you usually use, but try to get the ink consistent across the entire plate by rolling over it maybe 6 or 7 or even 10 times. Let me (us) know what it looks like.

I guess the card is one up which shouldn’t be to much coverage for two ink rollers. I would guess uneven roller pressure. Turn the press by hand until the rollers are on the ink disk and then stripe the rollers. Lift up the rollers hooks and see what kind of ink stripe is on the disc. This will give you an idea of maybe an out of round roller or one that is swollen on the ends. You may have uneven rails and your trucks might be of different diameter which can contribute to the problem.
I have turned printed pieces with difficult solids at an angle with the guides to avoid ink stripping. You kind of lie to the rollers and get better results.

Is the plate taller (in the direction of rolling) than the circumference of the rollers? (3.14*roller diameter) If so you are using up the ink on the roller before reaching the end of the form. Try double (or even triple) inking between impressions. That usually helps when I run into this kind of problem. That’s easier if the press has a throwoff mechanism.

You say the press is an 8x10, which can’t be, C&P didn’t make any that size. It’s either an 8x12 floor model or a 6.5x 10 tabletop. No throwoff on the tabletop.

A third roller will help a lot. Rider rollers (rollers that sit on top of the normal rollers) have been used carry a larger ink load, but they’re unusual on the smaller presses.

Also a larger form like this will use a lot of ink and an ink fountain will keep a steady supply of ink on the table. That will also make it easier to maintain color consistency between prints. I don’t much like them, but then I don’t print for money and I’ve gotten fairly good at judging ink load on the table by sound. When the sound starts to change, I add a dab of new ink.

Sounds like sound advice!