Image Stretching Issue

I’m trying to get familiar with the use of my Vandercook 3, and doing a lot of troubleshooting and question asking. I’ve made a couple of reduction prints on it so far (using lino blocks mounted to MDF and adjusted to type high with paper sheets as I look for a galley height bed plate) and the consistent issue that I have is a sort of stretching of the image as it prints. I get perfect registration perpendicular to cylinder, but the image seems to stretch and distort slightly as the cylinder rolls, so the near end of the image (right side of paper after removed)  is perfectly registered and it gets progressively further out towards the other side (the left side of finished image). A colleague has suggested that this might have to do with the rubber sheet that is mounted under the tympan, which i intend to remove and replace with extra paper and continue to experiment, but I thought I’d throw it into the mix here and see if it’s instantly familiar as a problem to anyone.

Image Stretching Issue

8 thoughts on “Image Stretching Issue

  • March 20, 2018 at 8:13 am
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    Have you considered paper stretch …is grain consistent and printing correctly according to grain….is each of first colour exactly in same place….has paper actuallystretched or image shifted…does cylinder fully engage with racking on impression that there is no play

  • March 19, 2018 at 12:49 pm
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    “If you have too much packing on the cylinder the surface of the cylinder is moving faster than the bed and will stretch your paper”. This seems to make excellent sense! A simple and Euclidean solution. I’ll report back after I get a galley plate and try another run.

    Much appreciated all!

  • March 18, 2018 at 1:46 pm
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    Standardize the heigh- to-paper of your form with a bedplate or galley (0.050″). All that paper makes your form springy, though your may need some underlay. Your lockup may be over-tightened causing the tail end of your block to be higher that the gripper end.
    As to packing, the cylinder undercut on most No. 3 is 0.070″. I generally start with three sheets of SuPak (0.016 ” each totalling 0.048′) and then three or four sheets of tympan paper (0.006″ each) as needed for a hard, uniform caliper.

  • March 18, 2018 at 1:27 pm
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    If you are bringing a form up to type high you need to put the paper between the bed of the press and the linocut. The packing on the cylinder plus your paper should only add up to the undercut plus the amount of impression you want. If you have to much packing on the cylinder the surface of the cylinder is moving faster than the bed and will stretch your paper.

  • March 18, 2018 at 12:41 pm
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    That seems possible, but as I said, I’ve made perfect impressions using this same technique on other Vandercooks, including prints with much larger areas of ink. My thought today is this- the press is “Galley height”, so it needs a metal sheet in the press bed to bring the bed up to a level where a type high block will actually sit at type high. Currently I’ve been compensating with sheets of paper to do this- and there are a TON of extra paper sheets under the tympan, making the actual cylinder extend a millimeter or three of thickness beyond the rails. I think these paper sheets are creating a lip where the cylinder end meets the gripper bar, and that lip is affecting the paper feed somehow- I noticed after printing that when the cylinder was all the way to the right the paper had slipped slightly from the teeth of the gripper.

  • March 17, 2018 at 10:25 pm
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    I don’t know why this would be an issue now and not before, my thoughts might not be relevant! Running it thorugh w/ no ink would still leave an impression that might look weird. The amount of impression and the amount of image area might be causing more stretching than the art you’ve printed before?

  • March 17, 2018 at 5:07 pm
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    Hey Dan! That seems like a difficult problem to solve. I’ve made prints using exactly this method on other Vandercook presses and had no difficulty with (I believe) very similar paper- but on this press I’ve used both some Mohawk stock that I usually use for screenprinting AND some 100lb lettra and had almost exactly the same result. Errrr, any other thoughts about how I could deal with it? Run all the paper through the press with no ink on the rollers before I print?

  • March 17, 2018 at 7:04 am
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    Hey Roger- Dan Selzer here!

    My understanding is that it’s simply the paper stretching from the first run. Mark at Haven Press had a great solution that unfortunately won’t help you, where he actually adjusted for that by stretching the second image digitally before making a plate. Likewise with plates or type people have been known to make adjustments, but that doesn’t help with a full image or a single large plate.

    Perhaps you can experiment with different paper stock? I also always wondered if it was possible to print something first, say outside of the image area, that would cause the paper to stretch?

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