OK, this blog entry is being posted a bit late - I wrote most of it, then went on vacation, yadda yadda. So I'm actually referring here to some printing I did a few weeks back:
I've had a frustrating couple of days in letterpress world. You might remember
these calling cards I printed a few weeks ago, which came out decently but overall I wasn't thrilled with the level of impression the paper took. So, I decided to order in some
134# Aqua Cranes Palette paper, since the 100% cotton is supposed to do really nicely with letterpress. It really is tasty paper, and I was excited to try it out. So on Friday I prepped my Pilot with the same calling card plate and mixed a nice deep green color. I pretty much ran into every problem across the board: not enough impression, uneven inking, un-crisp printing, too much ink, not enough ink, etc. It was just one of those days. So, I decided to just pretend it didn't happen and instead try again on my big 8 x 12 tonight.
Unfortunately, things didn't go much better. I'll start with
Problem #1: Uneven Print, and excuse the crap photo but I'm too tired to do any better:

See how the print is heavier on either side, like the "www" and "m"s in "com"? It gets lighter/crisper in the middle, but the edges just look really...squishy. I thought maybe it was just an uneven impression problem, so I spent a long time doing some serious makeready - cutting out individual letters from packing to try and compensate. The weird thing is, this exact same problem was happening in the exact same places on the plate when I tried the print on my Pilot at home.
Question: Could this mean that the plate itself is uneven?
As soon as it started to look okay, I ran into
Problem #2: Uneven Inking. Basically it seemed like a lot more ink was being laid down on one side of the plate than the other. There's a circular graphic at the top of the card, and it was really apparent that one side of the circle was printing more heavily than the other. Looking at the back of the cards, it didn't seem like the impression itself was uneven (indicating uneven platen pressure), so I thought it must have been the roller just laying down more ink on one side. I tried taping up the rails to raise the rollers on just the bottom of the chase, which only sort of worked. Since I don't have a picture, I'll do my best approximation via Illustrator:

Question: Is it common for uneven inking to occur vertically like this? How can I compensate for this?
This brings me to
Problem #3: Un-Crisp Printing. Once again, I'll do my best to illustrate this problem without a photo. The left side is what the graphic should look like, and the right side is how it has been coming out:

As you can see, there are some fine details in the flowers that should remain unprinted. Instead, the flowers are completely filling in with ink. I noticed that the problem got worse the longer I printed, so I'm wondering if maybe the ink was heating up and getting too squishy. I thought maybe the problem was simply too much ink, but when I removed some from the press all I got was a mottled print - incomplete coverage indicating too little ink but the lines were STILL filling in. The only thing I can think here is that I need to dry up the ink a little. I ordered some drier from Braden Sutphin the other day and will give it a try - but does anyone know if I'm on the right track here? I'm pretty out of ideas, and I know that a crisp print CAN happen along with a deep impression.
Question: Is ink consistency to blame when ink amount has been ruled out and fine details are still filling in?
::sigh::