Help! Trouble with SP15 Grippers not gripping paper!

Please help!

This is my first real troubleshooting problem with my press so I don’t have much technical experience. On top of that, I am more “creative” than “engineer” so please use laymans terms with me :).

Three out of the four grippers are not retracting to grip my paper at the feed board. The gripper pedal is working fine and the grippers raise up, they just won’t fall back down.

I am printing a job right now, so I’ve been manually pushing the grippers down to hold my paper in place, but then the grippers are not releasing the paper at the other end of the press.

Any help is appreciated!

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Your first step is lubrication—your grippers are little metal spindles sliding in a metal shaft…and sometimes the metal sticks.

Your Vandercook manual recommends powdered graphite. Go to a hardware store (one that makes keys), and ask them. It’s a little tube, costs just a few dollars. It’s the same stuff that you would blow into a lock to make the tumblers slide smoothly.

Powdered graphite is tiny flakes of graphite, so clear off your feedboard (and put a dropcloth or something over your rollers and plates). You want all the grippers exposed as much as possible. Squeeze the tube (it’ll be a little “puff” of air and graphite) onto each gripper shaft. Then release the foot pedal and press all the grippers down. Repeat until they slide cleanly.

If that doesn’t work, it’s one of the other many pieces that make your grippers move, and so would require a bit more investigation on your end.

Also, for future Vandercook questions, might I recommend the Vanderblog (http://vandercookpress.info/vanderblog/)? You’ll get ahold of the Vandy experts much more quickly that way.

Good luck!
Kelly

It is usually accumulated dirt that interferes with gripper movement (or sometimes over-tightened allen retaining screws). I wouldn’t add graphite to a dirty mechanism, but would clean the gripper shafts first, either a complete cleaning with disassembly, or a partial cleaning of just the exposed portion of the shaft. Then a small amount of graphite is applied; best is when the grippers are removed, and can be polished by rubbing the shaft on a graphited board, or you can rub some graphite with a cloth onto a gripper in place.
A problem with these grippers is that contaminants can mark the paper, which is why they are not oiled, and why cleaning with solvents must be done very carefully. Too much graphite can do the same thing, but in the long run too much of it can also gum up the mechanism in humid conditrions.
If the grippers are not releasing at the end, you might be grabbing before they open or after they close again. Tug gently and try to feel just where the opening is timed. I forget about the SP-15, but on the SP-20 there is a wedge projecting on the far side near the end thaat causes the grippers to open. On mine, there was a piece added to open the grippers earlier and stay open longer.

it might be worth eventually checking that the lever mechanism that actuates the horizontal wedge is clean and wedge properly greased up too…

Hello bethanybp,

I was not much of an “engineer,” either, when I started printing, but I soon realized that to be a good printer, it’s essential that you understand how your equipment works and that you learn how to maintain it and make minor fixes and adjustments. If at all possible, you should take a Vandercook maintenance workshop such as the one offered by Paul Moxon of the Vanderblog. I took one and it gave me the courage to disassemble and reassemble parts of my press for a thorough cleaning and lubrication. It’s not as daunting as you might think, especially if you photograph the process as you go so it’s clear how the parts go back together. I have a No. 4, and here’s what my clamp bar looked like before and after. It worked way better!

Barbara

The others have the right of it— cleaning the little popperuppers under the grippers is crucial. I soaked mine in paint thinner in a closed jar until I could wipe all the crud off. Once they are reassembled and properly lubricated they work pretty well. I have a #3 (non-motorized inking) and have only used it for proofs. Now that the grippers work, I’m planning a longer run!