Riso GR 3770 margin problem

[Thairiam]

Printing 11x17 sheets on 20 lb paper. Right margin keeps getting wider. adjusting margin with key pad on top doesn't help enough. Tried making new master with margin set all the way to right. Also adjusted pressure pads to varied positions. Still no help. Any ideas

Thanks

[Kopyrtek]

Timing and guide roller may need replacing.Also the drum drive set screw may need to be tightned up.

[Thairiam]

Thanks Kopyrtek your right about the drum. Just ran a bunch of copies with a different color drum and had no problem.

[Kopyrtek]

Glad to be of help.