I’ve noticed a pattern of wear on the bed bearers of my press. The wear is localized where the support rollers and the carriage bearings sit when the carriage is at the feed board. This occurs on both sides of the press, but the wear is more distinct on the operator side. I’m not sure what’s going on, how to prevent the wear from getting worse or whether I should be thinking about somehow repairing the wear that’s already there. I’ve attached a photo of the most offensive spot of wear. Any advice would be greatly appreciated.
Vincent
Not unusual. I have seen far worse. As Fritz suggests, this is not a major issue.
Gerald
http://BielerPress.blogspot.com
Here is a link to a scan of the assembly print I referred to and on the extreme left of the scan is reference to “see note L” that I quoted above. This also shows the position of the gripper bar relative to top dead center of the cylinder at the start position for the SP-20:
http://www.flickr.com/photos/53177163@N00/296258089/in/photostream
It may be from what Vandercook labels the “top carrier rollers” are set too tightly to the bed rails. These are shown in the manual as being X-2762 bearings. The assembly drawing states that these are to be set as follows: “With machine set on Print, top carrier rollers are to be set as follows: A – Rear Carrier Rollers to have .003 to .004 clearance. B – Front carrier rollers to have .003 to .004 clearance.” Thus, they are not to be set hard to the bed rails. The torque put on the cylinder when pressure is applied to the operating handle is causing the cylinder assembly to rock forward slightly and your front carrier rollers are biting into the bed rail, and the function of these rollers is to keep the cylinder assembly stable and level as it moves down the bed. I have seen these rollers set so tight that they dig into the bed rails creating a channel in the steel. For some reason, the bed rails on the SP-20 appear to be a milder steel that wears, and several presses have had to have new bed rails put on the press. This is not an easy or inexpensive fix, so don’t crank down on everything in sight when adjusting these presses. I’d check the setting of these rollers, adjust accordingly, and ignore the little divot. It is not in the impression area and does not affect the printing quality.