HELP! My Print Quality is Terrible! What’s the matter???

Hi,

I am printing on an SP15 and my printing quality is terrible!

I am printing personalized note cards with small type. The text is very uncrisp. It looks as though the ink is pooling on the outer edges of the letters and bleeding outward, while the inner parts of the letters look less inked.

I am printing with Van Son Soy ink onto 110# Lettra paper. I just started using soy ink. Could it be the ink?

My roller height is perfect. My packing and impression is fine. My rollers are clean. What the heck is causing my text to look so terrible????

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if i were you i would try some ink that isn’t soy and see if you have a problem, if you just started using soy ink and didn’t have problems before then i’d say its your ink.

It could also be the amount of ink you’re using—too much ink could cause the problems you’re describing.

Brad.

Post some pictures, but off the cuff, sounds like too much ink. If the ink is very runny, that could be another cause.

What you’re describing sounds a bit like severe ink spread and loose, un-tacky ink. The ink needs to be stiffened and made to be tackier so it will stand up to printing. Soy inks (and really, many inks) are generally pretty loose straight out of the can, unless a specifically tacky ink intended for letterpress.

Stiffen your ink with the introduction of magnesium carbonate; it comes in the form of a powder, and when mixing it the experience will be a bit like flour added to dough.

“How much mag should I add?”

Your ink is probably very long- meaning you can pull strands of it out of the can if you dip a knife into it, or that the ink is runny. In order to add the right amount of mag, you’ll need to feel it out. You do not add it to the whole can, either- just to small amounts of ink at one time.
The way to tell if you’ve added enough:
You ideally want to have a dollop of ink on the glass slab and to push a knife into it and have it ‘break’ when the knife pulls off and moves up an inch or so, meaning it’s sort of ‘short’. If you can push the knife in and the ink stretches out about 3 inches (or even longer) without breaking, it’s far too long for letterpress (in my practice, in a normal to warm printing environment). You should mix/work in small amounts of mag (like, teaspoon to large dollop/3 tablespoons of ink) until the ink becomes more difficult to work around on the slab. Then, test it.
Experience will teach you how much to add.

You want to increase the tack of the ink and give it more body/firmness; this will also increase resolution, especially when you’re talking about deep impression and finer details- which tends to cause a LOT more ink spread than normal printing impression.