inconsistent impression with photopolymer plates

Hello Ladies of Letterpress! We are still letterpress novices and could use your wisdom. The Press: Golding Official #3 Platen; the base: box car press deep-relief base; the plates: KF152 photopolymer plates from box car press; the paper: Cranes Lettra. We have several plates, all with fine lines and small text. One of the plates produces our ideal deep impression, while the rest leave no impression at all. We’ve tried both using the same packing and changing the packing when switching between the plates to no avail. We’re completely mystified. Thanks ladies!xxoo Grace Letterpresshttp://www.graceletterpress.comp.s. the photo is our press on the day we got it. it’s been given a lot of tlc since then.

Hi! Is there possibly anything in the way of the base that’s preventing the platen from meeting the bed? Are you placing the plate on the same place on the base each time? The press is so small that it doesn’t seem like the platen’s being mal-adjusted would be much of an issue, but you never know.

Thanks for your reply! The plates are different sizes and we were not placing them in the exact same place. The plate that does give a deep impression is small, maybe 1.5″ by 1.5″. The other plates take up almost the entire base, which is 3.5″ by 6.5″. There doesn’t appear to be anything impeding the function of the platen. While experimenting we kept everything the same, even left the chase in place, and just switched out the plates. I want to believe there is something inconsistent in the platemaking, but they all came on the same sheet. Now wondering if the size would make a difference…???Many thanks for your ideas!Holly and LyndsayGrace Letterpress

Size definitely does make a difference. Your press doesn’t have a huge amount of impressional strength. When you start with a little plate centered in the chase, it should be easy to get the sort of impression that I think you are looking for. But when you start filling up the chase, that same amount of force that is being used to print that tiny plate has to be distributed to a larger one…Poor example of a visual: Fill a standard glass with 2 cups of water. Pour 2 cups of water into a roasting pan. Same amount, distributed differently.

Thank you Colleen! I agree with you. The more we thought about it, the more our inner physicists came out. The distribution of force does seem to make the most sense. Guess we’ll be using smaller plates in the future until we can get ourselves a larger press. We’re working mostly on business cards right now, so that’ll be fine. More work, but hopefully beautiful results.Many thanks!HollyGrace Letterpress

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