Uneven printing

I have a quick question about my press, C&P 12x18- I am currently in the middle of printing a job for a friend and I cannot get the bed of the press straight. It is a little awkward and no matter what direction I twist the screws on the back of the plate, I cant get it to do what I want. I bought the very large wrench and I toyed with it for 4 hours last night- and no luck getting it even on all 4 corners. Any advice?
I know I need to have more patience and give it a few more tries, but I thought I would ask the expert for any words or wisdom before I pull my hair out….
Thanks for any advice you can give!

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First off, it requires VERY LITTLE turning of the bolts to get it right once you’re close. Second, you should get it at least close with something type high in the four corners of the chase and uniform packing on the entire platen so you are printing at the corners. Ink up and be sure that no corner is printing too hard, by closing the press manually until you feel resistance and backing off to check. Then adjust for the four corners to print evenly. Check to be sure that all four adjusters are bearing evenly — if one is off the platen will rock on two others and it will be impossible to get it right. Also, do this with the correct starting packing.

Bob

Awesome. This was my gut feeling.
Thank you s Bob!

Bob, What do you consider correct starting packing?

Thanks!

What I called starting packing would be essentially what you will use normally. I would set up with a sheet of oiled tympan paper in the clamp bales, under that a sheet of red press board, and two or three sheets of a relatively hard paper like 20lb bond or 60lb offset. With this packing you would adjust for optimum impression on the four corners. Then for a light forme you can remove some of the bond sheets and for a very heavy forme add some more. If you change the thickness of the packing very much from your starting packing you’ll have to re-adjust the platen bolts since a thicker packing causes the top of the platen to move away from the type forme.

Bob