Riso GR3770 image creeps

[bcp]

Hi My GR3770 has just started to do this. The image moves backwards from the lead edge of sheet over time. Need to watch and use the print position to keep advancing image forwards but after approx 4000 prints need to make new master as no more adjustment. Any ideas what problem is? thanks

[Iowatech]

Re: Riso GR3770 image creeps

Hi My GR3770 has just started to do this. The image moves backwards from the lead edge of sheet over time. Need to watch and use the print position to keep advancing image forwards but after approx 4000 prints need to make new master as no more adjustment. Any ideas what problem is? thanks

You might clean the master clamp on the drum, as it sounds like the master is slipping out on long runs.
Make sure the clamp plate isn't bent, too.
I think it could also be that the pressure roller underneath the drum has swelled up, causing excess pressure during printing that pulls the master out of the clamp. Hope that's not the case, as the only fix is to replace the roller, and new pressure rollers for the GR line haven't been available for quite some time.

[bcp]

Re: Riso GR3770 image creeps

thanks for that will try