strange marks on masters, need to clean the master making area??

[gillje]

I've had these lines appearing on my masters pretty consistently for a while, they're never the same, pretty randomly placed except that they only appear near the leading edge of the paper. Is it something in the mastermaking assembly that I need to clean? Have you ever seen this happen? I'm using a GR3770... any tips on how to resolve this problem would be appreciated! see attached pics.
stencil1.jpgstencil2.jpgstencil3.jpg

[ddude]

Re: strange marks on masters, need to clean the master making area??

Are they happening with the first copy or do these marks appear after many prints have been made?

What type or weight up paper are you printing on? If your paper is different from normal bond, the edges of the paper can cut into the master after hundreds of prints, causing the ink to bleed through.

[gillje]

Re: strange marks on masters, need to clean the master making area??

They'll appear with the first print and will remain till I make a new master. They are always small curly lines and longer vertical ones... They kinda look like fibres of the master material? I recently replaced the master roll and noticed a lot of these fibres around some of the rollers - as if the previous master roll had been shedding. I cleaned it up a bit but maybe I could give it a closer look, could this be the problem?

[jermyth]

Re: strange marks on masters, need to clean the master making area??

Are you using OEM Riso Master and the correct type for your machine? I've seen problems with generics cause this and even with Riso masters, but the wrong type for the machine.