Is anyone familiar with balancing the cylinder on an SP-20? Our 20 never seems to print well and we’ve balanced the base & made sure the rollers are seated properly to no avail. I’ve asked around locally & balancing the cylinder came up. Any instruction would be greatly appreciated–a step-by-step breakdown would be even more so.
Thanks!
Sarah
Before you break open that cylinder, try to find just about any other explanation for the problem. The SP-20s also have an adjustable drum roller. Check that out as well.
My experience with the SP-20, I think I have had four of them over the years, is that they are under built for their size and prone to mechanical problems. Though once you get them in tune they are capable of printing the sheet so that it sings.
But if you can, avoid opening up that cylinder, balancing these suckers is a nightmare.
Gerald
http://BielerPress.blogspot.com
p.s. If you’re not seeing both eccentrics located in the center of the impression cylinder spin a half-turn (on the operator side and the back), then it is definitely the trip mechanism giving you problems.
There’s also a chance that either a trip spring is broken, or that one of your trip-pins is stuck (common problem I think).
Roll your cylinder down to the foot of the press and throw your trip/print lever back and forth. You should have two silver pins shoot in and out of the press sides up near the drive cylinder.
If they aren’t both moving, either one is clogged with ink and dried oil and is stuck, or the long lever which ultimately moves the trip-pins has come loose. If it’s the lever (can’t find the part name, but it runs under the bed, behind the cylinder, on the outside of the cabinet – you’ll see it move when you move the lever), clear off the gunk, find the offending screw, bolt, and bushing, degrease, reattach (with some blue locktite), check that it all moves freely, and return to business.
If it is just a gunked-up pin, remove the trip-pin mechanism (2 allen-keyed screws) the remove the pin, and clean all. Oil lightly and reassemble. That should do it. Watch out for that spring too – it can hook you like a fish (trust me on this one).
If it’s a broken spring (which really probably isn’t the issue) call Fritz.
Maybe that will help, good luck!
Thank you, Paul. Much appreciated.
Gerald Lange has written the most thorough explanation which is posted on the articles page: http://vandercookpress.info/vanderblog/articles/lange-adj/.