Hi!
I teach at a university that has a Vandercock SP20.
I am looking for advice on how (if anyway possible) to alleviate uneven inking due to small pits in a press bed. We have a thin sheet of metal over the press bed to create the proper printing height, but we are still having inking issues. I have recently become aware that the press had severe rust, which was most likely the cause of the pits.
My first thought is to replace the metal sheet but I am not sure if doing so will resolve the underlying problem.
Thanks in advance for the advice,
Kari
Howdy Kari — I have an SP-20 and had to replaced the bed plate after I discovered the plate was warped and was experiencing inking issues. I did not realize that when I removed the plate that I should have placed the plate somewhere flat and not to have propped it up on-end (for several days) which caused the warping. I tried rotating and flipping the plate but still had to deal with how it effected the form and inking. After replacing it with a new plate, I have thankfully not had any issues.
I agree with Mr. Boyle, it would not seem that minor pitting on the bed surface would effect inking as the bed plate (if flat) would level out the pressure being exerted by the cylinder. Mr. Moxon and others may need to weigh-in, as the above are just my experience. FYI, I bought 18 GA Stainless Steel / .05 for the replacement plate on my galley-high bed. Where are you located?
Best regards,
Tony
Hi Kari,
Are you still having issues? If you want a second pair of eyes to take a look, let me know!
-val-
kari
I’ve had one more self-help ideas: flip the plate over to see if its now low in the middle and high on the sides. if it is, then the plate is likely the problem – if not, it’s something else
lad
press bed sheets are not very expensive – i would replace it –
As an alternative test, think about testing the press bed without the bed sheet to see if it is perfectly level. I think you can buy a lollipop that is galley high rather than type high – if you cant find one, improvise (maybe wrap the type high gauge with tape).
good luck and report back when you solve the problem
lad
Hi Lad,
Thanks for your response!
Yes the press bed sheet is bowed being higher in the middle and lower on both sides with one side lower than the other. Trying to think through how it could have become bowed. My only novice guess was that the air pockets created by the pits has caused the sheet to bow when heavily used. But honestly at a loss.
Am I safe to assume that you do not believe it could be due to the underlying press bed pits? Possibly we have a poor quality press sheet? It is less than 3 years old and only used for 2 semesters during those 3 years. This press is new to the school.
The rollers are new (3 years old) and well taken care of. And I don’t think it is a lock-up issue since this is an issue with both typeset and using a boxcar base.
One of the tests I performed trying to figure out the problem was checking the roller height down the length and across the press bed. The roller height does not stay consistent as I work down the length of the press bed. This in turn had me looking closer to the press bed sheet.
I cant see how small pits in the press bed would cause uneven inking if the bed is covered with a metal plate. Surely the metal sheet is not deflecting because of the pits.
The metal sheet not fitting snugly to the press bed could be a problem (I assume the press bed is galley high so the metal sheet is to bring it up to type high.) Is it somehow bowed?
There at lots of reasons you get uneven inking – problems with the rollers not being perfectly round is an obvious one. The form not being consistently the same height is another.