fading image on one side, cylinder unbalanced?
First, sorry for my english.
I own a 2028 KA Challenge Proof Press. It’s the first time I run some very large impression on it and it seems that the cylinder might be unevenly giving pressure on the press. Half of my impression is really faded, not from bad inking but from lack of pressure as I can clearly see. Things is, I did a whole new packaging three times, making sur that no paper was touching the rail on the side of the fading impression and the problem is consistent. I have put some extra packing on the fading side and it looked better, but I think I cannot just put always extrapacking on one side so it prints evenly. Does anyone know how I can adjust my cylinder height? I can post pictures of the press if it can help, I’ll leave directly one of the impression I made. If you have any idea of what problem it could be, maybe I’m wrong about the cylinder, but still when I have a small form anywhere on the press it prints evenly, I get this problem only on large forms…
Photo 3.jpg
https://d1mkprg9bp64fp.cloudfront.net/wp-content/blogs.dir/2/files/2013/02/ChallengeSeriesK_Parts-Manual-F-217.pdf
Ok so I found how to adjust cylinder height, I tried at the shop but they were hard as hell to move. Don’t know if I’m doing it properly, the parts are show in the document above, I’m trying to move the impression screws.
I’m afraid I have no experience with cylinder presses but one thing occurs to me. Have you tried rotating your forme 180ยบ and printing again? If the same side of the press is printing poorly, cylinder or bed adjustment is probably required. If the same section of art is still printing poorly it may be that the type is damaged. You may have already done this but it wasn’t mentioned in the message. My apologies if this is redundant.
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Michael Hurley
Titivilus Press
Memphis, TN
Ok so I tried for another 4 hours, the screw would’nt move.
And I did rotate the form another 180 degree to see what was going and the problem is not the form.
You might want to check over at Vanderblog (http://vandercookpress.info/vanderblog/). The Challenge was a Vandercook copy, and there are probably some folks that can give you more detailed instructions on how to balance out the cylinder. Depending on where you’re located, there may be a mechanic in your area that could help.
just doublechecking -fundamentally have you checked your type is type high…eg could be european height ..where did you get it from .this would lift a cylinder on 1 side away from the other…..
hi i am not familiar with the 2028 KA Challenge Proof Press but if i t have a rack and pinion mechanism make sure that it is very clean and free of paper dust mixed with grease that tends to be very hard ,and could elevate the pinion ihave seen this on heavy heidelberg cylinders.
It’s likely the bearings which hold the cylinder down on the form. I have a challenge 15mp and this would happen if they weren’t set correctly. Basically the form is raising the cylinder when it’s on impression. Check all your bearings to make sure they’re properly set and there’s no play between then and the surfaces they roll on.