New C&P, rollers different sizes?

I just got a new C&P 10 x 15, new style. I’ve been working through the kinks one by one and was taping the rails for my rollers the other day and couldn’t seem to get it right. The top roller had the perfect ink mark width on my roller gauge, but in the same position on the rails the bottom roller had a much larger mark. I used a caliper to measure the rollers and it seems that the bottom roller is a few mm larger than the other two rollers. Is this normal? I’m used to printing on a Kelsey 5x8 so the C&P is totally new to me. Also, it seems that the rollers are a little crooked as they go over the form, the right side is higher than the left side by almost a half inch. Is this normal? Thanks in advance!

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Sounds like you have adjustable roller trucks…. and they need to be adjusted.

Sounds like you have adjustable roller trucks…. and they need to be adjusted.

If you do not have Morgan Expansion Roller trucks, you should definitely get a caliper on all of your trucks and check them for uniformity. Do you have two rollers or all three?

DGM

All Rollers should be the same size. Trucks should be the same diameter as the rollers if the rollers are rubber. If the rollers are composition then the trucks can be a tiny bit smaller in diameter than the roller. If the rollers are anything else, I’d replace them.

Check the roller springs if one side is higher than the other. The springs should easily hold the rollers down tight to the rails. If not then the may need to be replaced.

I do not have the expansion trucks, the trucks are all the same diameter (checked with calipers). It’s the actual roller that is a different size. I have all three rollers and the bottom one is larger in diameter than the other two. Seems like I need to get new rollers? They are not in great shape (accidental pun) anyway.

Also, just to clarify, when I say that one side is higher than the other, I mean higher in a vertical direction. They are all tight to the rails, but the left side comes down a little lower the the right side as they move over the form. In other words, the left side reaches the bottom of the rails before the right side does. I hope that makes sense.

The bottom roller is the last roller to ink the form before you print. If that roller is bigger in diameter on one side, then it will probably slide slightly over the type (or plate) and tend to smear the ink and wipe it off.

You should put one of your proper size rollers on the bottom, and then whatever imperfections the bigger roller creates to the print, the good roller on the bottom should cancel out the imperfections. It would probably be even better to put the bigger roller on the top. Or, until you get another proper size roller, print with 2 rollers instead of 3.

If you do that, be sure the unused roller hooks are straight, as if there was a roller in them, so the hooks don’t hit the rails. (I can’t actually remember if this could happen on your press, but be aware that it could happen).

You are probably better putting the bigger roller on the top than taking it out altogether, because 3 rollers ink the form better than 2.

As far as one side of the rollers being higher than the other side, I think you mean that one side of the rollers is higher as measured between the rollers and the floor, than the other side.

The roller frames are the main castings on each side that hold the rollers. Both roller frames are bolted to the name plate in the back of the press. Are you sure the roller frames are bolted tightly to the name plate, and there is no distortion of the metal or anything like that? The name plate casting should keep both roller frames in line with each other.

Thanks for the responses. I ended up getting new rollers because the old ones were in pretty bad shape. I have attached a picture of the roller height difference. Like Geoffrey said it is from the floor. I checked the bolting to the name plate and everything looks normal and tight. So I am really at a loss as to what is causing it.

image: IMG_0061.JPG

IMG_0061.JPG

Diagnosis at a distance is difficult. It is always better to see and touch the patient.
The rollers look evenly spaced so the saddles seem to be right. You must measure to see if the top corners of the roller arms are the same height. They apparently are not, but you must measure. You may be able to check for level across the tops by removing the ink disk. To measure and compare the two heights, you will have to measure from the floor. This assumes a level floor.
You have checked to see if the arms are bolted tightly to the cross member in the rear. With rollers removed, get to the side and attempt to move each arm up and down with strong jerks. Make grunting noise. There should be no movement or very little. Movement will tell you something is loose. Then you have to find it.

The crossmember must be true, and the frames must be attached square to the crossmember without any debris or washers between the mating surfaces.

I would tie the press closed and remove the crossmember to check it for trueness and see if any crud is in the gap. IIRC, there should be dowel-pins to align the frames to the crossmember. If they are missing or broken, the press may have been damaged in transit. If the crossmember is not true, the arms might be made even using shims.