Re-spooling Tool for 620 Film

A simple tool to to help re-spool 120 film onto 620 spools for vintage and antique cameras. Prints all at once, just attach the top strap using a couple M3 screws. Printed in Matterhackers build series PLA at 220c, .3mm layer height and no supports.

To use, place an empty 120 spool on the winder side with your full 120 roll on the other side. Tuck the end of the backing paper into the slot in the take-up spool and wind on the first turn or two. Turn off the lights if you haven't already. Make absolutely certain that the room you are in is 100% dark or you risk fogging your film. If you don't have a darkroom or aren't totally confident that your room is dark enough you can also use a film changing bag (or better yet a changing tent.) Wind the film onto the spool, gently pinching it in your off-hand to ensure there is no slack. Keep your finger on the now reversed roll of film to keep it from unrolling and transfer it onto the idle side of the tool, then insert a 620 spool on the winder side. The process from here is essentially the same, with one extra step. The tail end of a roll of film is not taped down to the backing paper. You need to make sure the loose end of the film stays flat against the backing paper, which you can do by simply holding it down with your finger (It's a good idea to wear a glove for this to avoid leaving fingerprints on the film.) Once you are done make sure the film is tightly wound and doesn't bulge past the edge of the flange on the spool to prevent light leaks on the edges of the film. If you like the look of light leaks and don't mind risking the first few frames then ignore what I said and just send it. Use a piece of tape or a rubber band to keep the leader in place and you're done. 

I suggest practicing with a junk roll of film or a developed strip reattached to its backing paper in the light until you can wind it by feel with your eyes closed.