Impression leveling - left to right

There’s a lot of beginner’s discussion around here about packing and correcting impression from top to bottom with packing etc. Here’s a tough one…

Has anyone got any ideas for correcting the impression on a Heidelberg 10x15 from left to right?

I’ve had some trouble with a softer impression on the left-hand side lately (flywheel side) - it seems pretty consistent across different forms, lockups etc, so it’s not my lock-up. How does one go about leveling the platen from left-to-right?

Thanks!

Nicolas

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Maybe shingled tissues deep in the packing?

There is no adjustment left to right of the Heidelberg platen.
Maybe the bearing for the shaft that holds the platen is worn more on the left side,
To overcome this I would use layers of tissue within the tympan, starting at the left with a smallish strip and doubling the width of each strip until the fault is eliminated.
It’s what used to be known as “Make Ready” and the skill of the operator could be judged by the effectiveness of this.
This is from 50+ years of on-the-job experience.

Thanks, this is what I’ve been doing so far - overlapping tissue paper.

Bern: sure, but make-ready shouldn’t be so predictable. If I’m spotting up the same areas all the time I should look into replacing the bearings, as you say, rather than waste my time with repetitive make-readies.

Will call in a technician and post the results.

Nicolas

in the meantime, can you use a make-ready made up of 2 thinner sheets? if you were to then put your tissue in between themto level the press, and finish off your spot packing on top. you could then just change the top sheet each time and retain the bottom sheet with your “leveling packing” and reuse it.

Eric, that would be the prudent thing to do - just requires more diligence than I’ve had lately!

Will give feedback to the forum if/when/how it can be fixed. Mine can’t be the only Heidelberg in the world with differing left-to-right pressure.

Ciao!

I have just dragged this old chestnut up as there is a very important point re this “problem” with a Heidelberg platen .
I would happily bet on a couple of things here , one you are printing heavy impression .
Two you are printing on thick stock .
Three you have a chase that has the raised rib down the left hand side .(this rib is to balance the load on the plten during impression)
My thought here is that the lack of impression on that side is because the balance rib is holding the platen off on that side.
A quick test is to ink the rib and check see if it just licks the ink onto the tympan or prints it solid and definate . if the latter you will have to make an allowance to the packing beneath the tympan down that edge removing if it prints the rib .

Thank you Peter for that tid bit. It makes reading through the posts on Briar worth it when I can find a very useful tidbit like that here.

Happy New Year to all as well.

If you are concerned that maybe the main pivot bushes are worn (ie broken oil feed) or main bottom end bushes and toggles are worn.
Inch machine till platen face is closed put machine into stop position and place machine onto impression now grab platen face and physically rock forward and backwards.
If the is movement of more than a mm or so the the bushes are worn.
Hope this helps
Regards Paul letterpress services