Windmill is stuck - gripper problem
Hello letterpress friends,
My windmill is stuck in an open position and need help figuring out how to back the press on the older versions of 10x15’s. Would releasing the bolts at the back help even thought the press is in the open position already?
The first job i did on the windmill was creasing greeting cards and it worked very well. I few days ago I took off the die-cutting jacket to see how I go at printing. Today i was installing the die-cutting jacket back on but it seemed as if it had shrunk. I tapped in with a rubber hammer, then i was dumb enough to think there would be enough clearance for the grippers to swing past to tap the jacket more at the top but at the gripper wouldnt to go past the begging of the jacket. I have now created a jam and need to back the press.
I have tapped the jacket all over many times but it still sits just half a millimeter off the bed at the top.
possible factors:
cold weather shrinking?
there was dirt on the bed or under the jacket
I have not changed anything on the press that is obviously linked to the grippers’ operation.
So now, to back the press I have been trying what the manual says but my press is an older version and it is quite different to the diagram that explains the operation. do i have the right disk?
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I believe you have the right part, i think you move it toward the press, not the flywheel, and the press should be able to be backed up by hand. Dick G.
Thanks Dick. In the diagram it looks like the screwdriver is pushing upwards so that is what i was trying with no luck. I will try your suggestion next.
the die-cutting plates I use have a grub screw at the top about where the gripper is, if yours has a grub screw there and if so did you undo it before you took the jacket off because on mine this tensions the jacket and locks it in place and if you just prised if off without undoing the grub screw it will be difficult to replace and may account for your shrinking problem and not sitting properly.
I was able to back the press. You only need to nudge it a tiny bit. The grippers are now able to swing normal…
Except i encountered another problem. Now the grippers stop too close to the suckers and make the stock drop from suction without garbing it. They stop at an angle with the further side of the grippers closer to the suckers. On a cycle a gripper also grazed the side of the chase as the platen closed but is it seems to be just clearing now. Because both gripper are crooked at a similar angle of deviation it makes me think, is it a problem at the head rather than individual bent arms?
I have also checked and there is greater clearance (gripper to platen) at the outer sides away form the head. But up and down would probably not solve the problem of the angle of rotation.
Any suggestions please?
There is a adjustment to tip the succer bar, it helps when the stock is curled or for thicker or thinner stock. There is also an adjustment if the stock hits the gripper and fails to be picked up by the gripper, there is an eccentric that you adjust, you must stop the press when the gripper is open your succer bar should be toward the center of the gripper, if not you need to adjust the eccentric, this should be in your manual. Good Luck Dick G.
Iishii;
You might want to check the back of the feed table (part with seperator fingers) to be sure the pointer at the bottom is on the “0” mark. If it’s not the sheet won’t be picked up square by the sucker bar and then not square into the gripper. Ron
Thanks for the suggestions Ron and Dick.
Ron, the feed table is parallel. On mine the pointer says parallel paper margin but it must be “o” on newer models.
Dick, I located grub screw and have checked that it is matching the dimple inside.
Can the gripper head be adjusted to turn a few more degrees to be square with the platen?
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