I'm making a giant film slitter!

As the title says, I’m designing a film slitter. The capacity will be 14”x1000’, or way more than I’ll ever reasonably need. But I’m building it to try and make it as futureproof as I can.


This is the takeup assembly. The shaft will fit cores with a 1” ID and keyway, like most 2-3” OD cine cores. To allow for removal of the film, the shaft is 3 parts. The flanges and cores just slide on and off. The handle has a free spinning grip. Shown here is a setup for 240mm to 70mm.

Have you tried the concept in smaller size with a single blade yet? I can see many ways in which this can go wrong, esp. the film folding instead of cutting, then going off-kilter with ugly scratches all over the place.

So I assume next step is double perforation 70mm and 220 Looks like a nice design. I worked around huge extrusion equipment for making large sheets of ABS for appliances. As the molten plastic was pulled from the die lips, after it would stabilize going forward, the production folks would lower knives into the still soft plastic, worked slick. IIRC the sheet was about 65-70 inches wide, once cool enough it would be sheared to proper length with a quick chop of a huge blade. It was quite rigid when chopped.
The width was super critical as this sheet would eventually go into a vacuum thermoforming machine that would form an entire interior of a US style refrigerator/freezer.

Looking forward to seeing how you get along.!!!

Just remembered I saw slitting operations for the horrible fruit leather candy Fruit by the Foot. The strawberry goo was extruded into a width of about 2 feet, knives were dropped to slit this stuff, and it would be chopped and rolled up like a tape measure. Smelled amazing.