Combination of crosses. SM 102 5+lac.

Beru a new job I print 10 sheets I combine the image. My rubber then I print 10 sheets and combination of crosses almost exact again, I move once again registers and I start to print circulation. And that (crosses) combination turns out especially purple color disperses, there is also a yellow cross 0,5-0,3 millimeters follow up. It is necessary to move once again registers in circulation, and after that everything is normal. If to turn off supply of paper on the last sheets combination of crosses disperses, and on a leaf on an illustration strips appear. Why?

 

If I understand the issue correctly, that being your circumferential register is unstable immediately after an adjustment, but improves after making additional minor adjustments, I would suggest locating the grease zerk (fitting) on the plate cylinder double gear assembly.

 

Yes I greased there where you told, two months ago. But it didn't affect in any way. Didn't help

 

Alignment pin (inner gear) and bushing (outer gear) may be worn. So too, might the brass bushing on the outer gear, which is supposed to slide freely, but without play, on the journal of the inner gear.

 

How to check it?

 

Probably not a task for the inexperienced. Basically, you must remove the yoke that is securing the outer gear in place. With the heavily spring loaded yoke removed, you may then examine the alignment pin and bushing, and the condition of the brass bushing of the outer gear and the journal of the inner gear. Depending on the age of the press, this may or may not be the route to go. I'm also not thoroughly convinced that I am fully understanding the problem you are experiencing, as the translation in your original message is not fully clear to me.

 

My understanding is he makes perfect register and when he starts printing y tends to move backwards 0.5mm so he adjusts with circumferential movement and achieve register yet again until machine stops

He could be refering plates sliding away from clamp bars or servo motors gone bad and move plate up and down of their own

 

Thanks for the clarification, Mantman. I have seen, and advised on this issue countless times over the years. Many pressmen are not aware of the grease zerk on the inner face of the outer gear of the plate cylinder drive assembly. It may be simply an issue of the brass bushing being starved for grease.

 

This grease point applies for SM models only or it can be found on GTOs?

 

No zerk on GTO. If you're experiencing similar issue on the GTO, look for the the shouldered pin held in place by 4 6mm bolts, it may help to remove, grease and maybe turn it 180 degrees.

 

there is a bit of a work around you can do until you get the press fixed. I would try to perform the make ready with the press running. Get your color and register close while running the press at slower speeds if the job allows. I would use a couple of pulls to make sure all 4 colors are diagonally in register and fine tune the circumferential register while your getting color at about 6000 sph. This is of course if you have a few hundred sheets to waste and are able to ok your own work.