Rollers & Trucks on 8x12 C&P

Hello all,

I recently bought a New Style 8x12 CP. I replaced the rollers but kept the old trucks. Today I tested out my Box Car Standard Base with a Deep relief plate - I know but that was the only base available to me and the plate was an old one I’d had from previous use still in good condition…

The plate did not ink evenly, in fact almost half of it did not get inked! Part of the boxcar base was getting inked unevenly too (top left corner). When I switched one truck from each roller to the opposite roller, the inking stopped all together! The impression of the plate came out fine on the paper. But the form was not all inked so the print came out half inked, half blind.

Has anyone had experience with rollers being too high and uneven at that? If so, do you know how to fix it? I see talk abut adding tape to the rails or trucks but that seems that would only raise the rollers.

Thank you kindly,


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Check the diameter of your trucks with a caliper micrometer — they’re probably all different. Polymer is very picky about inking and if the rollers are a bit out of round or the trucks are worn you’ll have trouble. Also check to be sure the base is dead flat against the bed and there is no junk on the bed that could lift it in one part. You ought to plan to get a lollypop roller setting gauge for printing with polymer.


Thanks Bob. Checked out the base and it is flat. The rollers and trucks are also the same diameter. It seems I just needed to tape the rail heavily at the upper left part where it begins to curve to release the rollers onto the inking plate.

Using the lollypop was a bit more tricky on this press than a vandercook! Thankfully, rollers seem to be inking pretty evenly now.

One more question, my press is run by motor and has a large leather belt connecting the spinning shaft with the gears. If I put the motor to a fast speed, the centripetal force causes the belt to fly off. I’m trying to find a good solution of keeping that belt on by adding some sort of lip to the spinning shaft on the motor. Any ideas?

I’m not totally clear what you mean by “a large leather belt connecting the spinning shaft with the gears”. Normally the wooden motor pulley is about 3 inches in diameter and a bit wider than the belt, and “crowned” a little, higher in the middle than the ends, which tends to keep the belt centered on the pulley. But if the motor shaft isn’t exactly parallel with the driven shaft on the press the belt will work its way off the pulleys. Also, be sure you have the belt tension tight enough so the belt doesn’t “bulge” between the pulleys at higher speeds.

In theory a couple of flanges added to the ends of the motor pulley should keep the belt from flying off, but you shouldn’t need them — that drive system is as old as the C&P press.


Only to reinforce what Bob said.
You should not cater to the symptom. Treat the cause.
The motor shaft and the press pinion shaft and attached flat pulley must be precisely parallel. And in line.
Both the motor pulley and the pinion shaft pulley require a slight crown. On the pinion shaft pulley two strips of electrician’s tape around the circumference with a third one centered on top of the two will make a satisfactory crown.