coating breaking up

jerrybia

New member
we start a job, and check the strip to the blanket,4-5mm. after we run about 8 thousand sheets, it starts to break up in the middle. and the strips on the end are about 8mm and the middle is the same. the press is a 56 inch mitz with a harris bruno coater. the cylinders have a good strip to each other
 
Have you checked to make sure there aren't any lowspots on your cylinders? Are you running enough back pressure?
 
I would check the loading pressure of the harris-bruno unit. On our 40" press we set it between 25 to 30 lb. of pressure depending on the age of the blade.
 
I would check the on/ off pivot pins on the hangers they get coating in them and hang up just enough to cause you pressure problems. I have pulled and cleaned the pivot pins with emory cloth greased well and re-install.
 
Maybe the blankets are being distored by the heat, I have had this happen before on Heidelbergs.
 
try using a torque wrench to tighten the blanket to spec. Are you coating over an ink that has a lot of wax in it?
 
Did you ever solve this problem? I've been getting the same thing on a 28 ins mitz for 5-6 years!! Seems to be pressure related maybe, but why i don't know, or maybe heat?
 

PressWise

A 30-day Fix for Managed Chaos

As any print professional knows, printing can be managed chaos. Software that solves multiple problems and provides measurable and monetizable value has a direct impact on the bottom-line.

“We reduced order entry costs by about 40%.” Significant savings in a shop that turns about 500 jobs a month.


Learn how…….

   
Back
Top