http://vandercookpress.info/vanderblog/2006/10/23/grippers-snap-closed-when-cylinder-at-feed-board/ »A forum for flatbed cylinder proof presses Sat, 22 Nov 2008 09:18:22 +0000 http://wordpress.org/?v=2.6.3 http://vandercookpress.info/vanderblog/2006/10/23/grippers-snap-closed-when-cylinder-at-feed-board/#comment-100 The Arm NYC Tue, 24 Oct 2006 20:37:23 +0000 http://vandercookpress.info/vanderblog/?p=84#comment-100 Eric, Thanks for this information. My mistake was in assuming that the gripper bar was meant to be vertical. When I only return it as far as the top being parallel to the feed board lip (downturned 5 degrees as you described) it operates normally. So what I now have to deal with is the fact that there is nothing behind the bumper springs at the feed board end so their adjusters have no effect. I wonder if NA Graphics have the part I need to make these operate correctly. These parts and a set of rubber feed tapes are all I need to have this press up and running... Next, I will be troubleshooting the die cutting 320G! Eric,
Thanks for this information. My mistake was in assuming that the gripper bar was meant to be vertical. When I only return it as far as the top being parallel to the feed board lip (downturned 5 degrees as you described) it operates normally. So what I now have to deal with is the fact that there is nothing behind the bumper springs at the feed board end so their adjusters have no effect. I wonder if NA Graphics have the part I need to make these operate correctly. These parts and a set of rubber feed tapes are all I need to have this press up and running… Next, I will be troubleshooting the die cutting 320G!

]]> http://vandercookpress.info/vanderblog/2006/10/23/grippers-snap-closed-when-cylinder-at-feed-board/#comment-99 Eric Holub Tue, 24 Oct 2006 17:31:34 +0000 http://vandercookpress.info/vanderblog/?p=84#comment-99 If the 320G is similar to the 325G, the feedboard is at a 5-degree angle at the lip, and the top of the gripper bar is parallel to that, which is one tooth forward of vertical. There is some adjustment with the bumper springs, but the rest position is determined more by the gripper trip assembly (far side, visible when cylinder is moved forward). On a G model, the roller rides over the auto wedge portion and comes to rest behind it. From there the footpedal activates another rod that raises the grippers from the rest position. I'd check that all parts of the gripper trip mechanism are present and functional and lubricated. I have a particular problem with the spring that holds the wedge back. The original was too weak, and my replacement keeps breaking. Click, boing, snap. Bend a new hook from the stub, and back to work. --Eric Holub, SF If the 320G is similar to the 325G, the feedboard is at a 5-degree angle at the lip, and the top of the gripper bar is parallel to that, which is one tooth forward of vertical.
There is some adjustment with the bumper springs, but the rest position is determined more by the gripper trip assembly (far side, visible when cylinder is moved forward). On a G model, the roller rides over the auto wedge portion and comes to rest behind it. From there the footpedal activates another rod that raises the grippers from the rest position.
I’d check that all parts of the gripper trip mechanism are present and functional and lubricated. I have a particular problem with the spring that holds the wedge back. The original was too weak, and my replacement keeps breaking. Click, boing, snap. Bend a new hook from the stub, and back to work.
–Eric Holub, SF

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