Gripper Won’t Close (doesn’t bite down)

Hey everyone, I am in need of some advice.

One of my Windmill grippers is not picking up my text stock. Worked great on double-thick cover but appears to not be closing tight enough to grab the text weight. Rubber is in tact, gripper is level (not bent) and clean (no build-up or gum).

I think after picking up a large stack of double-thick cover, it’s possible that the springs got spread out too far to then come back together all the way. The top portion of the gripper is closed tighter than the bottom portion (the part near the arm is good, the part near the guides, at the bottom of the platen is slightly open (at least enough to not hold the stock).

Is there a way to adjust this, or to help that gripper get back to the closed position?

Thank you so much for your time in helping me understand how to get this gripper back to the closed position.

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2 possibilities for starters,!
(1) on both gripper arm assemblies there are 3 springs, are all 3 X 2, all intact, and can be adjusted up independantly, via small Allen Head grub screws.

(2) in both cases the final closing, for adjustment, is obtained via the small double ended, Left and Right adjusters, for each gripper finger, loose, broken, mal-adjusted. etc.

As you imply, >top portion of the gripper etc,< springs would seem to be the primary suspect, possibly check all 6 via the use of a “Fishermans” style spring balance, for overall mean average pressure.? . . generally each spring is anchored at one end in a dedicated hole, the other end works/rubs/ contacts the body of the gripper, but does not get oiled enough, friction and paper dust make bad companions, and the tail end of the spring(s) wear through.!!!

Mick! Thank you for the help.

I went out to check the springs and they ARE broken. Two of the three springs have broken off at the hole where they are supposed to be inserted. I have a couple backup grippers that I can use until I can get this one repaired (if that is something that can be fixed!?)

I am thinking that should fix the problem.

L. & C. Thank you for the “Nod” appreciated.

If all else fails, I have a pair of grippers on-sight, and would be Happy to dismantle them, A, to talk you through the procedure, and B, to mail them (6 springs) Letter-post.
*** ONLY if you can not access/acquire Stateside… Our Graphic,s suppliers are well equipped for H/berg, Parts.!!

*** Certainly do not want *Wittenburg* invoking the >the Guy at the gate (Yours) with a Gun in a Violin case, syndrome< . . as in “Doorway to Hell” Film from 1930.???

Good Luck. Mick

TESA tape, rubberized. Any bindery will have it. They use it for their folder rollers cut in strips its self adhesive and will solve your problems.

Nick, how will TESA tape fix a spring?

springs are usually weak, HDM used to sell these Tesa materials in strips as they allow for variances between one end of gripper to the other. If the springs close a gripper and the gripper is not damaged or bent, a rubberized tape will give much better grip.

Interesting, thanks for the tidbit!