Printing large solid areas

I am printing a x-mas card with quarter -size solid circles with type below the circles (pms 7474 on Lettra 600gsm w/ photo poly plates) but the circles are not solid but have a mottled look to them. I’ve tried hitting it harder to no avail and also more ink but that changes the color. What am I doing wrong? Help!

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When you say mottled, how bad is it? Just to make sure your not talking about this effect:


Thank you!! I guess saltiness is the correct letterpress term and that is exactly what is happening to the solid circles. I guess I’ve been hanging out with wrong crowd(offset press operators) Is this something that will happen often? I am guessing it is from the articles you linked. I’ve seen solid areas look a bit better but on lighter stock. Thank you again! Is there a unwritten rule (or written) that letterpress peeps can go by,e.g. 220 gsm will hold a solid better than 600 gsm?

Patrick, you may not be doing anything wrong. Solids are an area of weakness with letterpress, like the links to Beastpieces describe (so wise on their part to make the client acknowledge it by the way). Cylinder presses do a better job of laying down a solid, but if you are working on a platen, the best you can do is:
• add a little more impression
•add a little more roller (which cures some variants of mottling)
•affix the rider roller (on a windmill)
•mix your ink lighter (I prefer opaque white to add opacity to the solid) which enables you to lay down more ink and still acheive your desired color.
Some people add an ink conditioner, but I prefer not to.
Hope this helps

I’m an absolute beginner on letterpress, but I’m guessing that a smoother paper could help (not necessarily lower gsm, but less textured), as I’m guessing that even the slightest variations in the surface will impact the ink-deposit.

Like Bill suggested, I’m guessing a less viscous/tacky ink will help as well?

It’s one of those many things that can vary so much from paper to paper, press to press, not to mention from printer to printer, that you’ll just have to spend a while experimenting…

When trying different things, I suggest you take notes and keep the things you print, that way, if you find an application where a certain look would be approriate, you’ll be able to reproduce it… =)

Just take a look around the beastpieces blog and you’ll see plenty of applications where the saltyness adds to the quality of the product, instead of being a negative.


Kim’s right in saying that a smoother stock will help. Try some cast coated stock sometime just for kicks. Because there is no ink absorption, it makes for nice solids. The thickness of the stock doesn’t matter as much as the finish. Cylinder printing makes for nicer solids, but the stock has to bend around the cylinder, so you can rule out the double thick stuff.
Listen to Kim - make lemonade out of those (salty) lemons!

Thank you Bill and thank you Kim, My background is foil stamping and embossing where ‘salty’ is a bad word but now I’ve learned to embrace the ‘saltiness ‘in my life!


Mottling has three basic causes, stock that is too rough, not enough pressure, and not enough ink. You can compensate in various ways. The key is to “bottom” the ink on the paper to eliminate mottling or “saltiness”.

Experiment with the following:

1. increase ink levels on the press or use a slightly thinner ink. You have to watch with this one because you can end up with “squeeze” where the ink squeezes out to the outlines of letters. You can increase ink and decrease pressure. Thinner inks may help compensate for rough paper stock by running into the paper easier.

2. keeping ink levels constant, increase makeready thickness to see if you can push through some of the roughness of the paper stock. If you already have the maximum amount of punch or are afraid of damaging your type, you can double strike the form. With grippers on and paper well fed to level gauge pins, let the form hit the paper twice. This will deliver twice the ink but at the same pressure, and can often eliminate mottling since the first strike levels the paper (mashes it) and the second one lays down fresh ink on a more compressed area.

3. to compensate for rougher paper stock, you can change paper stocks, or you can dampen your stock before printing. Dampening makes the paper more receptive to ink and at the same time softens the fibers of the paper, allowing for more flexibility in the paper and consequently better bottoming of the ink.

4. If double striking or increasing ink changes the color, mix your color with opaque white instead of transparent white to the PMS hue that you want. Transparent white keeps the same color but pushes the pigment molecules further apart giving the illusion of lightening. When you double strike you lay down more pigment changing the saturation levels back. Using opaque white when mixing eliminates this effect.

While mottling is something of a given with letterpress, you can eliminate it in most cases with the steps listed above.

Good Luck,


I wanted to mention that I recently experimented with dampening my paper before printing, and the results on large solids were game changing.

I’m now planning to build my own humidors to integrate dampening into my usual process.

James Beard
Vrooooom Press

I second James’ suggestion. I learned printmaking in undergrad where we dampened all of our paper, usually through a damp pack method that allows the paper fibers to get loose and ready to snactch up that ink. Definitely give it a try.


I was recently having ink coverage problems as well and decided to do some experimenting with make-ready.

I found out that if you put a softer sheet of packing above your press board, directly below your tympan and helps considerably when printing a large area.

Worked great for me!