Sirius Glass
Subscriber
In the Hasselblad back, film transport is by driving the take-up spool, and as the film gets wound up on it, a turn of the take-up spool moves more film, so there is a natural tendency to need a bit more force to move the film. This is subtle, but noticeable if you are careful. When enough film has been moved, the clutch in the back releases and lets you complete the shutter wind - at which point the wind gets easier. This change happens sooner during winding as the spool builds up, because it does not need to rotate as far for the same amount of film.
However, the film shifting to one side towards the end of the roll, and the paper getting bunched up on one side is a red flag. The film running crooked in the back definitely adds friction to the end of the roll. I've seen this on a back or 2, and I think I can trace one back to the insert being dropped on a roller, which caused it to be ever so slightly crooked.
I have never run into the problem of the paper bunching up. That is a CLA problem.
One cannot complain about the paper running crooked when they know that they dropped the insert and it is out of kilter. A repair problem, not normal operation.