10 x 15 windmill gripper arm adjustment

Is there any type of adjustment for the gripper arms? One is registering perfectly, and the other is not feeding into the gripper squarely. Also how much gripper bite should I be getting? One of my 10 x 15’s has a 1/4” bite. The one I’m having trouble with has an 1/8” bite on the good gripper bar and a not square bite on the of about 1/8” on my trouble gripper bar.

Thanks, Todd

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You probably have already done this…but I would inch the press slowly to pinpoint where the problem is occurring. Is the gripper bent? Is the sheet slipping while in the gripper? Is the sheet crooked when it is grabbed by the gripper? Look and feel inside the troubled gripper when it’s opened up and ready to grab a sheet…is something there causing the sheet to be crooked?

To my knowledge there is no adjustment to the gripper arm short of replacement. I’m not sure what’s going on, but you may have a bent gripper arm. Take a close look to see if you can see any warping. If so, you may be able to manually bend it back into shape. I’ve never done this myself, but I’ve seen someone else pull on the gripper arm to try and straighten it. It worked.

It also sounds like you run without the guides. You could probably eliminate the problem by running with the guides engaged, and you would not have to rely on the gripper arms picking up the sheet perfectly square each time.

Good luck,


Vertallee Letterpress

This sounds like a crazy thing but an old Heidelberg Tec told me that to adjust the gripper arm you have to bend them. It doesn’t take much of a push or pull to get a large move so take it slow

hya toddmi ran a windmill for many years and there is no reconised way to reset the gripper arm, however a little bit of a pull will work o.k. but be carefull also inside the gripper is a rubber lining. check that is o.k. if it is worn,a piece of very fine wet &dry auto rubbing paper usually does the trick

the gripper arms on the heidi are trouble because they hit things when operators make a mistake. As you know they only move from left to right and the first test is to measure each arm independently at pickup position to see if they are square to the pickup paper stop. if one is different, that is crooked you may be able to bend it back after removing it from the cast iron arm that supports it. bending either arm while on the press puts the arm support in jeopardy.
Arms can be bent both ways up or down and the end towards the press or away. Arm maintenance is required to oil the springs with light oil often and of course the oil holes. Slight pressures should only be used if you try to correct one of the arms, putting an arm off and on the press can be a pain but is the better way to protect the casting that holds the arm. The inside surface of the arm is coated with a rubber material when new and after much use the rubber material wears uneven, because most people run their work in the corner of the chase. Careful scrapping of the old material and replacing it with “good brand of electrical tape” will restore the arm for some time depending on the adhesive on the tape.

I am having the same problem. Have you resolved your’s yet?


There are two tools that are used in “shaping” the gripper bars on a windmill. The actual “bending” is done to the gripper bar support casting. This casting is made from “malleable” cast iron. there is an “s” shaped bar that is inserted under the casting and pulled upward. There is a two prong bar that is placed on top of the casting and pulled downward. Using these two bars, you correct any variation in the distance of the individual gripper bar to the platen surface. (Approx 2 points). there shoud be a .07 mm gap between the edge of the platen and the edge of the gripper bar when the gripper bar is locked (12 o’clock and 6 o’clock position). the bars must have the same clearance and be perfectly even along the edge of the platen. Bars must not drag on the jacket (if used) not the tympan. Bending and shaping the aluminum bars is frustrating most of the time. Rebuilt bars are available from several sources and once the gripper bar carrier casting is straightened, rebuilt bars will usually clear up the rest of the problem. Remember, when the press is running, don’t walk away! It’s just waiting for you to turn your back so it can jam up and help me make another boat payment.