Ink drying problem

Hello everyone,

It’s my first time printing with the heidelberg 13x18. We have been using it mostly for die cutting.

We are printing some cards, and having problems getting the ink to dry on a 600gsm cotton stock. I’m using Vanson Rubber Base Black ink and have the powder sprayer turn on.

The ink is smudging on the next card pilling up on the tray.

Any ideas?


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The easiest solution is to switch to an oil base ink. Make sure you wash up the press and ink knife at the end of the day; it dries hard overnight. Fritz at NA Graphics stocks it.

Run less ink or drop a slip sheet after every sheet.

I used rubber-based ink once when the same problem happened to me. I’ve never used it again. Oil-based ink is where it’s at man.

Run less ink and only build up small piles in the delivery before you take them out, so the sheets don’t press down on each other too hard.

With that heavy stock, I assume you are pushing the impression (and ink) below the surface of the sheets. That being the case, I’m not sure how you are leaving ink on the surface of the sheets where it can transfer to the following sheets. Try reducing the roller pressure so the rollers don’t get ink on the shoulders (the sides) of the image areas of the plate.

Ink can dry in three ways, absorprtion, evaporation and oxidation. If a stock has a hard surface there will be little absorption and I presume with a rubber base there is little evaporation.
Vanson ink as I am told is a ‘stay open’ ink which I presume means it takes longer to dry than a letterpress ink.
Use letterpress ink which mainly dries by oxidation. Cobalt drier can be added to speed up the oxidation process. Add too much drier and the ink will dry on the rollers before you have hardly started printing your job.
Don’t be tempted to use litho ink which carries more pigment per unit than letterpress ink and would need thinning.

I have a print run now, and I’ll have a rubber base ink on the press for at least a week. I won’t have to wash up every night. My rule is to make sure the ink will dry before I run the entire job. Do an ink draw down the night before, or at least several hours to make sure the ink will dry completely. Rubber base saves me a ton of time, but I am very careful which jobs I use it on!

If you are pulling small lifts of stock from the delivery pile, it can help to then place them vertically rather than horizontally to reduce set-off. A type rack can provide many ledges.