Re: photopolymer printing issue
In regard to the first problem, if a portion of the solid image isn't
printing as evenly, it might be just a matter of an underlay under the
weak area (under one corner or edge of the base). If the problem is in
the center of the solid, you likely have rollers that may be swelled
on the edges. Makeready is not really a big issue with photopolymer,
except that the packing should be fairly hard and even. Tape (as
makeready) is never a good idea.
You didn't mention what type of plate you are using or what kind of
base. Could be important.
If your A's and e's are filling you are overinking and/or your rollers
are not set properly. Or the viscosity of your ink is wrong. I'd also
recommend roller supports when printing on a Vandercook.
That "nice sculptural impression" that you love could as well be the
culprit, especially if your inking is incorrectly adjusted. Once you
make impression an aesthetic issue, you've created a technical problem
for yourself that may not be solvable.
--- In PPLetterpress@yahoogroups.com, "thistleberry_press"
> Hello to all, my name is Bethany and I was recently invited to join
> your group and am thrilled to have a source of expert printers to
> ask my silly questions :). I am relatively new to the art of
> letterpress, and have ventured into the arena of photopolymer plate
> printing but keep running into the same problem when printing solid
> areas from these plates. There seems to be a portion of the plate
> that prints just a little lighter in color than the rest of the
> solid area and I have done all the things that I know how to do and
> wondered if anyone had any advice. I've checked the rollers for
> anything on them, I've built up the area with tape but that tends to
> leave a line through the rest of the design so that's out of the
> question, I've cleaned the plate a dozen times to ensure there is
> nothing on it, etc. I'm working on a Vandercook 4, use Van Son oil
> based inks, and Somerset, Pescia paper. Could it be a problem with
> the plate? I usually assume it's something that I'm doing wrong, but
> I can't seem to fix this problem this time and all my other plates
> when in the same position on the press bed print evenly. Any help
> would be greatly appreciated. Now to the second question: Is there
> a way to print on soft cotton stocks like Somerset, get a nice
> impression, and not have the ink fill in the little holes in the A's
> and e's? I have a tendency to have this happen when I'm printing on
> these papers, and I have taken out packing but then I lose that nice
> sculptural impression that I love. Any advice?