Inconsistent inking
So, when we recently had our Windmill 10X15 worked on, it was necessary to remove the rollers, after which we replaced them, though we can’t be sure that we placed them back in their same positions (this may or may not be relevant).
Roughly since then (two weeks ago), we’ve had a problem with inconsistent inking in two main ways. First, a strip of the image (approx 3/4”) is lighter than the rest, although it’s in a different place each time. Second, in trying to overcome problem #1, we’ve increased the impression somewhat, and when we do, (and it doesn’t need to be very deep for this to happen) the edge of the copper plate(or magnesium, as the case may be) makes contact with the paper.
These are the main things we’ve attempted:
*We adjusted the roller height, and are now consistently getting a stripe of about 1/8” on a type high gauge.
*We discovered that one of the trucks was a little worn, and we wrapped it with tape.
*We’ve experimented with packing.
*We’ve tried both oil and rubber ink, including some that we’ve used before without any issues.
*We’ve tried other plates that have worked well before.
*We’ve tried every combination of roller placement (I *think*)
*We’ve tried various amounts of ink.
Here’s what the strip of lighter ink looks like. Note that it’s in different places on the form. The orientation pictured is how we are printing it.
Any thoughts/ suggestions?
Thanks in advance,
Matt
Misprint 1.jpg
misprint 2.jpg
BTW, those images are not big enough to clearly show this, but the ink seems to mainly be getting on the edges of the raised portions of the plate (the “type”), but the body is left rather hollow. Also, for what it’s worth, it’s not printing perfectly in other areas, either….
Thanks again,
Matt
It sure looks like the rollers are skidding on the type. Are the trucks tight on the axles and engaging the keys so they can’t shift at all? Are you sure they’re turning freely in the hooks — if they stick at one point that can well cause this problem. (And of course I know nothing about Windmills so these comments may be WAY off base!)
Bob
As you say the orientation is how you are printing, and that the fault occurs in different positions of the forme, then the only thing I can think of using my 50+ years of experience is that there must be a flat spot on your bottom inker roller; (ie It is not perfectly round). Try swapping the inker rollers around, or better still replace the lower roller.
I don’t think its a skidding problem, as if it was the ink would never adhere to the paper and you could wipe it off even weeks later.