Help!! Ink on Edges of Photopolymer Plates
Hi all - I am relatively new to letterpress and in need of help!
What’s been happening is that on my plates (it’s happened on 3 so far) the ink gets spread not just on my print, but on the edges of my plate (PHOTO ATTACHED) and even when I rub the ink off the edges of my plate each time, I’m still getting ink in unwanted places on my prints! ugh…
I’ve tried moving my plate around the press bed, messing with the height of the rollers, adding more paper under my prints, yelling at the letterpress, and this problem still follows me…
It has never happened to me before this week!
Is the press haunted??? Any ideas?
Thank you so so so much for reading and for any advice you can lend.
Happy full moon! (maybe that’s it?)
Jess
Hi
If you are sure the rollers are set corrrectly then it must be the polymer height, have you checked that it type height? If you are using a chase base, are you using the correct polymer thickness to go with the base. All things to check.
I would also check if your base has lifted from the chase. Unlock your quoins and let your base rest on whatever surface you are using to lock up. We sometime have inking problems from over tightening our quoins, which results in one corner of the base lifting and creating an uneven surface. Remember that you don’t have to muscle your quoins so much, they should be tightened little by little, until they are just a quarter turn past finger tight, and your chase passed the “tap test” where you can lift the chase and tap on your type and furniture and nothing moves.
Your rollers seem to be touching the floor (non-printing areas) of the plate. This can only be due to either 1) the rollers being set too low, or 2) the floor of the plate being too high. Assuming the rollers are set correctly, then the floor of the plate is too high. The floor could be too high because 1) the whole plate is too high, or 2) the plate doesn’t have enough relief (the relief is the difference in height between the printing and non-printing areas). Regarding 1) do you have any reason to believe that the whole plate is too high? If you are using a metal plate base and a means of adhering the plate to the base, are you doing anything differently? Regarding 2) does the plate look like there is less difference in height than usual between the printing areas and the non-printing areas?
Regarding the 3 plates that it has happened to so far, did you get them all at the same time and from the same place? Probably the most likely cause is that the platemaker has not washed the floor of the plates down far enough, leaving a floor which is too high. If you can rule out the plate base having a different height for any reason, and if you are sure that the rollers are set correctly, then I would think this would be the most likely cause.
Another reason I think the floor might be too high is that it is high enough to 1) get inked, and 2) to print, so it must not be too much different in height than the printing area.
Are you trying to make a deep impression? Is the paper laying flat on the platen? These could also be causing the problem.
Thank you all! Mystery solved. (At least I hope) It seems like the rollers on my press were set too small, and I am not a seasoned enough printmaker at this point to have realized without your help! Thank you so much for your thoughtful replies.