Need help with sakurai 574EPII

Taking pack out or adding it on the blanket wont adjust the register if you adjust the plate packing it will affect register. it shouldnt be impossible to Get Register at the back of the sheet. in fact with the autoplate and plate cocking it should be perfect because your not stretching the plate when your tensioning the back edge

 

I already try and YES, I can get register for unit 1 to 3. For unit 4 it's almost register. I think I should use packing as thin as 0.05 mm. I will search and try again. Thank's Rolandman for your advice. Hope today I can make register for all unit. Thank's again.

 

with all register options set to their zero position is the amount off consistent from one job to the next, and from one unit to the next? if there is consistency in plate positioning from one job to the next (ie. each unit requires the same move in order to register the job) then your dealing with a need to adjust your plate clamps to accurately hang your plates square. Im not familiar with how sakurai adjusts squareness of their plate clamps but ill bet their are provisions for adjustment. My suggestion is to find just how the plate clamps zero position adjusts, and with your consoles plate cocking feature set to the middle of travel on all units, hang and then register all plates imaged with a fine line grid to cover a full sized sheet. Do not use your consoles plate cocking feature to register the grids but instead do it accurately with the mechanical zero positioning adjustment on each unit. When youve succesfully and repeatedly found all your plates registering to each other then your job is done. Modern press manufacturers dont allow for all that much movement in their plate cocking feature because the assumption is that with an accurate and working ctp system the plates are being imaged pretty darn square. my thinkin is that if you can get .40mm from limit to limit on your plate cocking feature your doing pretty good. With a correctly calibrated ctp imager and corectly adjusted plate clamps .40mm should be more than youll ever need.

 

5 years ago I ran the 4 color version of the same press and had exactly the same problems. I would run out of cocking adjustment on the console and had to make some moves manually, but it wasn't consistent enough to just be able to square the clamps. I also had the same problem with the last two units not fitting front to back. I use to have to put a piece of the thin paper that they put between the plates in the package behind the plates to shorten the image. I guess you get what you pay for.

 

are you getting movement or is it constant and are you getting any double on the print??? mabey try and put a micron clock on the plate cylinder bearers and the impression cylinder bearers and the blanket cylinder bearers if there is movement in the bearings then you should pick it up there if you have no movement there then you could count out the bearings