Two big rubber rollers turn solid and chunks come off.
Two ways to fix it. 1) Remanufactured new part from KHB photographic.
2) http://www.largeformatphotography.in...ighlight=d5500 (points to my thread on repair with some large rubber o-rings)
Since getting a motorized Durst, I thought it would be cool to motorize one of my D5500 columns but those motorized units seem to be pretty rare.