which roller and table material to use for aerial film slitter?

[John Kasaian]

Hello! I'm trying out a new design to slit aerial roll film from 9-1/2" to 7" so it will fit the 7" spools used in the Keystone F8. I've got the design figured out except that because I need to transport the film from a spool of one diameter across a table and onto a spool of a different diameter, I figure on using rollers to keep the film moving across the table which will be higher up than either spools. I'll be cutting the film emulsion side up to avoid damaging the emulsion, but what would be the best materials to use for the rollers and the table to avoid scratching the back of the film? Polished stainless, chrome, or copper? Some type of plastic or nylon? Thanks for any suggestions!

[Ralph Barker]

Depending on how much space is between the spools, and how you're handling the cutting process, John, I think I'd lean toward a sheet of plate glass - 5/16" or 3/8" perhaps. Something similar to what you might use as a squeegee board for prints. The other thought I had was a large felt pad, vacuumed clean before each use. If your design calls for some sort of tensioning rollers, you might try to find ball-bearing inserts, and then use plastic pipe, carefully smoothed with 600-grit wet/dry, then washed.

[Bill Jefferson]

Polished Stainless Steel. Your biggest problem will be dust and static electricity

Bill