Polymer not being inked

Hi letterpress printers!
I am having a heck of a time with my last 2 print runs! Can someone please tell me; is this my press or my polymer? I got the polymer made at the same time, so I wonder if it’s perhaps faulty poly? I run a Vandercook 320G and in the 6 years of using it, this has never happened.

Someone please help me figure this out!

Many Thanks,
Amanda
Silverplate Press

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You’re getting impression, so the polymer appears to be doing it’s job.

You don’t say if the lines of type are parallel or perpendicular to your rollers—that could tell you where the problem is.

I see a few possibilities:
(1) some greasy or solvent residue on the polymer preventing the ink from sticking
(2) if your type is parallel: your rollers are out of round (oval) or swollen in the middle, shrunk on the edges (and therefore not getting inked)
(3) if your type is perpendicular: you have gunk on your rails that’s lifting the roller rack out of place

How old are your rollers?

Wash the plate good. Use a press wash.

On the second photo the larger image seems to be inked properly adjacent to the image with which you are having problems. Was this run at the same time as the smaller type image?

Since you are running a Vandercook, I would change MayDay’s #3 to check the gear track the rollers are driven by to see if there is some paper scrap of something else lifting the rollers slightly as they pass particular areas of the plate.

It also appears that the inking is better where there is more image area, which would make me check to see if the rollers are turning properly as they pass these lighter areas. Sometimes the rollers will actually be driven by the plate image, and skid on the lighter image areas. Not likely on a Vandercook unless the rollers are turning independently of the gears. If this is happening, the woodruff key (a semi-circular piece of steel) which fits in the slot in the shaft, holding the gears in place on the shaft, may be missing, and the rollers are not being driven by the gears. That might be a long shot, but worth a look. You can find replacement woodruff keys at most good hardware stores.

John Henry
Cedar Creek Press

Looks like the plate is inked down the middle and left and right you have impression, no ink.

Take a Form roller off the Press, place a sheet of paper on you stone and place the Form roller on it, place a good ruler length wise on the Form roller and check against Light if you see any gabs, a good Roller show no light gap.

Few little *Think outside The Box* suggestions:- as impression appears to be O.K. but apparent lack of Ink on the actual image, is Ink present on the image, prior to actual impression? implying that rejection from the actual stock.!!
Has the stock got unseen, localised, foreign chemical fault, possibly sacrifice a few sheets, rotated 180 degrees or work and turn, ditto.?
Perhaps hold one Failure up to strong light/back light, looking for Water Mark Style imperfection caused by presence of unwelcome chemical, maybe even Ex manufacturing process.!!

******
Follows a >Disgusting Blast from the Past<
******.
With all the will in the world and with all the modern, SOLVENTS, CLEANERS, DECONTAMINATES, etc. etc. Nothing but Nothing beats Human Saliva, Spittle, for the final wipe across the face of the image, be it Metal type, Wood Type, Process etched Plate, P.P.

Look up “”“Spittle”“” on Wikipedia. the minute %age, in the formula is the important point. Disgusting Yes, try it just once on the final wipe if ink rejection is suspected.!!

Thank you all for the your comments and help! There is definitely no residue on the plates. They’re squeaky clean. It seems to be a roller issue. The rollers are 6 years old. And the problem does seem to be running parallel to the rollers. I turned the form 180ยบ and it fixed the problem for the most part. There were still areas bring affected but those areas were much smaller. It worked to just finish the run, but it seems like it’s time to get these rollers recovered.

The top 2 photos was the same run and the 3rd photo, was my previous run.

Also, confession time; I left my rollers down accidentally overnight. And it started doing this after that. Maybe they warped?

Thanks again everyone for your input!
Cheers,
Amanda

If you’ve never had rollers recovered before, you’ll be amazed how well they print when new! Much less guessing and makeready time once you get them dialed in for the first time.

Also sounds like you have some aging hard rollers, so it’s possible leaving them down on the ink plate overnight would slightly deform them. It doesn’t take much.

As your Rollers are so Comparatively new that would seem to be a very small portion of their expected life? and as you imply that they may have indentations by default, and before investing in Brand New or recovered, presumably at some cost, do your suppliers do part exchange to retrieve the Steel Stocks, Is it possible/practical to ascertain (if at all) whether any of your Stateside suppliers REGRIND in otherwise good condition rollers??. .

Your own *Tarheel Roller & Brayer co.* out of Clemmons, N. C. >[email protected]< may be worth a try for this type of advice.
They apparently, do everything In House as opposed to Farming it Out @ + 25% or more.??.