4-plex theatre complains prints wind too loosely on takeup; on all platters, all decks. This makes for difficult print moves. On my visit to the site, I find I can press the edge of the print in about 1/2". I do not know if this is par for Christies or not... never had this complaint before, so I've never had a reason to check.

These are older units, with non-removeable center feedout plates. The platter timing checks out fine, motor drive wheels are in good shape and gripping, and no prints with damaged sprocket holes.

The only thing I can think of, that would let them wind tighter, is a tighter spring on the takeup arm (giving the takeup deck more mechanical resistance). Has anyone else had this trouble before?

I've done this and it works perfectly. Just make sure you don't up the tension too much or a slightly misaligned roller can cause edgeweave. It doesn't take much at all.