Smooth ink coverage? Tack issue?

Hey folks.

I am having trouble getting ink to smooth out on press. I have plenty of pressure, plenty of ink, and the surface (of pre-cut coasters in this case) is pretty smooth. But the ink still has a mottled look to it. Any tips?

Would decreasing my ink tack help? How would the best way to do that be? Tack reducer or Van Son smooth lith? Or do I need more tack? Add whiting or something like that?

I wish I had extra time to just experiment, but time is kinda hard to come by these days, so I though I would pick your brains first.

See linked pic for reference.


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It would help to know on which press you’re printing. That kind of coverage on a platen press is going to be very difficult to get consistent, especially on smaller presses.

Dampening the coasters would be an easy but time consuming fix.

Looks like many little specks of the white coaster stock are showing through in the areas which are supposed to be solid blue. You are not getting ink down into the tiny low places in the stock. As has been previously suggested, dampening the coasters may be the best choice.

If you don’t want to dampen the coasters I would say the following: either you don’t have enough impression, or you don’t have enough ink, or both. I would try more impression first, little by little. However (also as has been suggested), if you don’t have a press which is capable of delivering more impression without being stressed or broken, you can’t do that.

The next thing would be to try more ink. However, if you put down enough ink to get into the low places in the stock and print those large solid blue areas well, you may also put down enough ink to fill in the fine reverse type with the website, and the thin reverse outlines in the solid blue.

Regarding the fine reverse type with the website and the thin outlines, both of which are reversed out of the blue, it probably would have been a good idea to make them bolder on the art, to avoid just such a situation where you might fill those thin lines in with blue ink and lose them.

Thanks for your comments guys.

The press is a C&P 12x18. I am using a Boxcar base with their deep relief plates.

Dampening the coasters isn’t an option because the quantities are almost never less then 500 and as many as 5000. I’ve done that on Lettra and it does work, but it’s a PITA.

I have as much pressure as I can put on the coasters without stretching the surface to the point of cracking and breaking. There is a lot of impression. I would say as much as .02 passed a “kiss” impression. It’s very “crushed”.

My packing is Tympan Top Sheet>Red Press board>Various hard packing>platen.

I am pretty sure it’s an ink thing. When you look at the coasters from The Cranky Pressman / Parliament of Owls (link below), their solids are much much smoother. And I did print a second coaster job that night with the same ink and it was only about 50% ink coverage and the solids have the same appearance as the ones I linked earlier.

The only thing I could have tried was lowering my roller height to see if that helps smooth it on the plate, but I’m afraid of filling in the finer type and putting ink down the edge of my plates. The press is inking the plate fine IMO.

My rollers are in good shape and are only a few years old. Smooth surface and have been taken care of. It’s not like the roller texture is transferring to the plate.

I understand the shortcomings of the process when it comes to solids… but I still believe it should be better then this, I have seen examples of work that is better.

I advise my clients on the limitations, but it’s ultimately their call on the final art. I just want to make it look as good as I can.

Still looking for a good answer.


Woody, I’d recommend running ink film thicker rather than lowering the roller height. Lowering roller height won’t transfer more ink to the face of your plate (unless your rollers are too high now) it will just start to ink shoulders.

Have you tried skip feeding them? This is somewhere in between regular printing and dampening in terms of annoyance, but might be your best bet.

Large coverage like yours I’ve always seen best printed on a mid-sized stop-bed cylinder press. Heidelberg cylinders have 4 forms (as well as a nice ink train) to deliver solid coverage, and pressure on a cylinder press is much higher overall as small amounts of the form are printed at once.

Are you at least feeding 1-up? Do you have an ink fountain? Seems like it would be very annoying to keep colour consistent over a run of 5000 adding ink by hand.

Unless you’ve got a Rice or Kluge feeder hooked up, I’d recommend looking into an auto-feed press as well. Runs of 5000 are no fun hand-fed. They are not all that expensive.