Uneven Platen, and Ghosting/double impression

Hey guys! So, I’ve had pretty good luck so far with my C&P 10x15, but recently fell into a huge problem. I’ve read every thread I can find about my symptoms, but having little luck fixing my issue. Here are the details, and I hope someone can help me.

I am printing a steel backed PP from a patmag base. The size of the print is about 5.5 inches tall, by 4.5 inches wide. The current plate is all text, but I’ll also have one a little taller that is mostly solid. The last few nights, I’ve been trying to get the platen adjusted for an even print, and failing miserably.

I started by lowering all four of the adjusting pins as far as I could. I pulled an inked impression on the right side of the platen, almost centered vertically. The impression was very faint (to be expected with the adjusting pins all the way down) on the TOP of the platen, but pretty clear on the bottom. Basically, the top of the platen was not even kissing the entire sheet, but it was a pretty even discrepancy all the way down the print. So, I started adjusting the top pins, little by little, and pulling impressions after each adjustment. Slowly, the print started looking better (keep in mind the bottom pins are still as far down as I can get them).

Once I finally get the top pins to where the impression appears pretty even, I start getting a double impression. It literally looks like 2 impressions, the first of which is VERY faint, but quite noticeable, and the second is a clean-ish impression. So, I looked at my adjusting pins. The top pins are almost all the way up.

What’s wrong here? Is my platen screwed up? Why would my bottom pins be all the way down, and my top pins all the way up, for an even impression? Additionally, why would I be getting this ghosting impression once the impression depth looks about right?

Any help would be greatly appreciated. I spent about 6 hours last night and 6 the night before adjusting the platen pins, and I’ve about had it. I started over 10-12 times, at least, all with the same final result. I just don’t know what else to do. My wife said maybe it’s just the right side of the platen, and thought I should try switching to the left, and see if I get the same results…but it just frustrates me that I can’t figure out what’s going on with the right side….please help!


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on a 10x15 you should not have to keep adjusting the platen. i think you need to lock a letter in each corner of the chase and place your normal packing in the press and get it adjusted. sounds like some of the plate is text, the rest is a solid, the solid might need more pressure to get it to print, either makeready under the top sheet or behind the form, i would not keep adjusting the platen, good luck dick g.


“…The current plate is all text”

the pressure is evenly uneven, if that makes sense. the impression fades from bottom to top evenly.

Could you explain what you mean by double impression?
Ghost images are a result of inking problems, and can be solved by adding a distributor roller, sometimes by remixing the ink (for more opacity for example). A slurred image on the other hand results from paper sliding against form as they come into contact. Things like decurling the stock, positioning the grippers or adding fingers, friskets, rubber bands or strings can help the sheet to lie flat; also make sure the form isn’t rising from a bowed lockup.
Normal practice when levelling the platen is to put a large character in each corner and adjust the screws until each is printing evenly, to a regular amount of packing. Change your regular amount of packing and re-levelling may need to be done. Adjustment for the form is done in the packing; adjustment for the form by the screws is not generally recommended (I admit I sometimes did that when I had a C&P, but I didn’t have any trouble re-levelling).
It is normal for even a centered form to be heavier at the bottom than at the top, and as you add packing overall it will get worse. This is because of the design of the C&P, with platen and bed hinged together. Try feathering packing so that layers are added to the top of the form without adding to the bottom. Bury these layers lower down in the packing so the steps aren’t visible on the printed sheet.

Have you rotated the base? perhasps there is something amiss with the lockup which is causing it to lift on one edge?

Is the plate migrating across the base? How old is your Patmag? It could be that the magnets have lost strength. I hear the Patmag bases’ magnetism is a lot less than the Buntings even when they are new.

Daniel Morris
The Arm Letterpress
Brooklyn, NY

could be a problem with inking, do you have the third roller onthe press, could be your rollers are slidding and not turning when going over the form. good luck dick g.

There’s no problem with inking, like I already mentioned in the original post. It’s clearly the impression. Inking is even, the impression is the issue. It’s pretty easy to see the difference between inking and impression.

The Arm NYC,
The plate is not migrating. My bases are only a couple of months old, PLUS I also tape them down. Thank you for your insight. :)

I’ve rotated the plates, but not the bases. I can try that, but I have 4, 3x4 bases, all butted up to one another, creating enough area to put the plate. Because of this setup, an imperfection would have to be uniform across all 4 bases, and all be in the same direction…which I don’t think is possible but Thank you for your suggestion.

I’ll try your suggestions, and I’ll also try to post photos tonight. Thank you

Your rollers are sliding and not rolling.
Clean the rails and the trucks of any oil.
You may think this is trivial but give it a try.

As has already been said lower all of you impression screws. Lock a block or wood type in each corner and increase the impression until you have an even print. The double image may be caused by a worn raceway in the main gear. This will cause the platin to shake.