Chatter Marks

[kasperheim]

Running a Ryobi 4 color press we are getting "chatter marks".... I am not a press operator. I am the pre press person trying to help... Any suggestions or solutions would be appreciated.

 

[rathishvm1]

Chatter marks

Chatter marks

Running a Ryobi 4 color press we are getting "chatter marks".... I am not a press operator. I am the pre press person trying to help... Any suggestions or solutions would be appreciated.

Dear Mr.Kasperheim,

Are chatter marks caused by,
case 1) over packing of blankets or,
case 2) is pressure setting of blanket & plate cylinders proper?

If case 1 is the cause, backlash of gear teeth must be measured and blanket packing suitably altered.
If case 2 is the cause, cylinder eccentrics / bearing taper roll condition need to be checked. Hope seniors would concur with the opinion.

 

[twooodogz]

Running a Ryobi 4 color press we are getting "chatter marks".... I am not a press operator. I am the pre press person trying to help... Any suggestions or solutions would be appreciated.

Not sure if it is possible but if you can post a jpeg of these "Chatter Marks" I can probably diagnose just by seeing it.

 

[turbotom1052]

chatter marks are often caused by incorrect pressures somewhere. Id make sure that your printing heights are at factory specs. The plate needs to be at the correct height. The blanket needs to be at correct height. The impression needs to be at kiss impression. if after checking and correcting all this and you still have the marks id then look to roller pressures. Roller pressures need to be set to spec and you need to know that the rollers that are gear driven are in fact being gear driven with no broken gear teeth anywhere. The friction driven rollers need to be free of any binding in the roller bearings and set correctly. if all that looks ok then id look at the drive of the water form roller. one way you can isolate the water form roller as a potential problem would be to print a dry solid (without water roller engaged to plate) to see if the chatter marks are still appearing. this testing should be done with an ink thats prone to a chattering mark. id suggest something like a pms 452 to test. if after all this you still have the problem then perhaps its time to call in a press mechanic. Good luck in isolating your problem and keep us posted as to the results.