Heidelberg Platen clutch progressively tightening

Hello, quick question - on those Mammoth printing days where we print for a good 8 to 12 hours, over the course of the day I find that the clutch on the press (Red Ball Heidelberg T Platen) becomes tighter and tighter to engage. The next day we start the press back up she is back to usual.

We keep it well oiled and greased, so my thought it that as it heats up over the course of many hours printing something might be expanding which is causing it to become progressively harder to engage. Anyone else experienced this or any thoughts on the matter?

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I am sure you are referring to the lever that you push sideways to engage the clutch, if you are you will just have to get oil into it, the lever and work it till its free .
However , if its the clutch itself you cant engage yo may want to clean it and reassemble ,readjust and have another go , unless its really been hard used it may not need replacement .

Hi Peter, Yes its the lever. We give it plenty of oil and make sure its all well greased. Its just so strange that it only happens after many many hours of printing and slowly it gets harder and harder to engage?

I have known them to get tight but usually a bit of oil and a few wiggles sort it , sometimes it serves to take the lever off and orientate it upside down to get the oil in deep ,its only a smallpin you have to remove to get the big pin out and then remove the arm , take a few minutes and is quite easy . If heat was causing expansion i would wonder how its heating up ,if the press takes off like a whippet after a rabbit the minute you start to push it out i would check see if the clutch is heating up considerably ,should that be the case have a look at the adjustments and slacken the adjustment off a little ,obviously if its already warm the problem may persist till it cools . I would think its probably a bit of temperature and oil as well as possibly you get a bit weaker as the day goes on too .
I will have a look see if i can make a lever do it ,it is possible the spring in the handle that sorts the toggle position is bound up somehow ,although without looking at one i can be sure just yet .