Okay, so it is possible to handle a 400 foot spool while loading
cassettes manually. I envisioned a small hell trying to keep the
film taught to keep the big spool from unwinding (does such a
huge amount of film do that?) while trying to cut off a suitable
amount for one roll. My plan for using the 100 ft spools was to
limit the times I'd have to handle the 400 ft spool to 4 times,
and then being able to use a normal bulk loader. It would even
allow me to make several pre-rolled 100 ft spools, so with 4 100
ft spools and 4 containers I could actually get rid of the whole
big spool in one sitting. But getting spools and containers is
the catch, I don't want to have to use up 400 ft of some other
film before I can start using the motion picture stock.  BTW,
does anybody have the dimensions for the "hole" in the middle of
400 ft and 100 ft spools? I'm planning on making a small
"machine" in which I can load the 2 spools and then just crank
on a handle to load the smaller spool. And are there any
difference in th