My image of scrolls where completely shattered from the small paper wrapped around a dowel when I attended a Simchat Torah celebration a few years back. It is when the last reading in the Torah is read followed quickly by the first. The only way to get from the last passage of a 20+ lb. scroll to the beginning is unwinding from one dowel and winding it back onto another. The whole process took almost an hour.

One of the things I noticed is that the winding wasn't even. It ended up being wound tighter or looser almost randomly. Also the edges weren't flush with the edges above or below. They would stick out from or disappear under the wrap above it.