110 Lettra Image
We had a 4 x 4 110 Lettra card. It had a lot of bold type that had an outline built in to make it even bolder. The text was around 14 -16pt and closely spaced. Most of the closed loop letters ( lower case o, a ) has almost no white space. The more ink and and impression we gave it the the worse it looked. As we gave it more impression the text began to almost fill. It was like I was hitting a sponge with a hammer. Am I missing something? Is there some trick I don’t know about or am I just fighting a battle I may not win.
When printing deep into a substrate, you need to be certain that the ink on the plate or type is not carrying over from the face to the shoulder of the letter. If the letters are inked only on the surface, the image should print cleanly and sharp.
We backed off the rollers until there was no inking and gently came back to inking so we would not over ink the plate. The image printed clear but with a salty appearance. As we added ink it got better and added impression it flattened the the fibers and stopped the saltyness. But by the time we did that the image was plugging somewhat. We backed off the ink and skip feed it to give an extra roller pass over the plate. I was not sure if the on off motion of the impression was adding to my issues. It became a contest of hit vs image clarity. We have anyways wondered if it is easier to get a deeper hit on a thicker stock. We have always looked at impression like a swimming pool and wondered if there was any relevance. With a 20 point stock you bottom out faster getting greater resistance from the packing ( the shallow end of the pool hitting the bottom), vs a 40 pt stock where a deeper hit is easier for the stock to take and absorb with less pressure caused by the packing ( the deep end of the pool - even my 2 beer cannon ball does not touch bottom).
I doubt very much that a heavier stock is the solution, depth is easier, sharpness is not. You need a sharp impression with a correctly inked plate to avoid the infill.
If you are having trouble with salty coverage when you are getting the inking set just right, one option might be to dampen the paper so it more readily accepts the ink and you won’t need to overink for coverage.
First you must accept the fact that the press and type were not designed to do deep impression printing on heavy soft stock. To deny this is to lead to continued frustration.
To achieve the heavy impression on soft stock can be done with a lot of careful work and patience. Read and accept the words “careful” and “patience”. Compromise is another to keep in your vocabulary.
You have done some good experimenting so far. The first thing to accomplish is good inking. Without that no amount of cursing and arm waving and messing with the packing will do any good. Kiss inking of the face of the type is necessary. Visualize one piece of type, or one letter of a poly plate. If there is any ink over the edge of the face and down the beard, that ink will be wiped off the side of the type as it is driven down the hole into the paper. Bad.
Kim’s suggestion on dampening the paper is the next place to go. More tedious work, but often very successful.
You should also use very hard surface materials in the packing of the tympan. You want to compress the fibers of the paper so as to provide a solid and even impression to transfer the ink. If you are using a soft packing, the “give” of the packing will not allow for good ink transfer.
John Henry
Cedar Creek Press
Thank you all for the feedback. We do listen and learn from what information you supply to us, now if we can just remember tomorrow what we learned today.
Jhenry- We pack using blanket press packing sheets we use for our GTO press that I have in various thickness. I would not call them soft but wonder if something stiffer like a card stock might work better.
Good advice in here, but I like to avoid dampening stock whenever possible as this changes it dimensionally a little bit. If I can get it to print dry I’m really happy, and especially if I’m working with something like the windmill which can be touchy with the feeder- damp stock is not my preference if Im not hand feeding.
So if I were seeing this issue:
Two solutions- # 1 will seem counterintuitive at first.
#1: the ink and press-
More tack to the ink (need to add magnesium carbonate or body gum or start with a tackier ink), then start lean and add slightly more ink, slightly less roller pressure, back the platen pressure off a little and don’t push anymore than 40% into the stock; tackier ink that is more viscous will plug less and behave how it should. If you have a rider roller, install it even if you aren’t seeing lap marks.
#1 B:
If you can dead on register, you might want to print a pass with VERY little ink, let this dry, then run a second pass same register. If your register doesn’t change, you’ll be able to hairline register and achieve a black that will not plug.
If you are doing a long run where you need to make multiple piles of work, IE many chutes like a 25000 piece run or something crazy, you just run every pile twice. It’s slower going but does the trick.
OR
#2: the plate-
You can plan for the ink ‘spread’ in advance next time. .3 pt stroke around a sans serif glyph/letter that is 18 pt, in bold, shouldn’t change the style or legibility too much once the ink spreads. You might have slightly less sharp corners, but if it’s really plugging up that much they’re already rounded out.
It really sucks to buy a new plate if one has already been bought, but this is somewhat the advantage of plating in house- one can ‘tune’ photopolymer for example by changing the film a little and really tweak the form until it is perfect if one wishes.
Or just, you know, settle for the best inking of the form you can achieve.
Thank you all for the feedback. It looks like we are on the correct path and your input helps us pick a direction instead of walking backwards which we quite often find ourselves doing lately.