Today I started making myself a Bolta spool for the Ikko Sha Start 35k from a 12 exposure cassette of Konica VX100 35mm film (expired in 2004). The Ikko Sha takes 35mm film, but instead of using a cassette, like nowadays, it uses unperforated 35mm film on a paper backing.
The Bolta spools are slightly different than normal 35mm spools in that the Bolta spools do not have the part that sticks out of the top of the 35mm cassette, they are flat, again like 120 spools. They also have a rectangular hole in the top of the spool, which fits into the film advance knob of the Ikko Sha. It might be possible to modify a 35mm spool to fit into the Ikko Sha, but I have not explored this just yet. Fortunately, two Bolta spools were provided with my Ikko Sha, which meant that I did not have to worry about making a 35mm spool fit into the camera.
I could have loaded bare 35mm film into the camera and light sealed the body. Then I would guess how much to turn the film advance knob between frames, which I had determined was one and three-quarter turns. However, if the film was anything like my paper mock-up it slid around and I could not guarantee that the frame spacing would be accurate. I therefore decided that I would try to respool a 12-exposure 35mm film onto the Bolta reel with a paper backing cut from an old 120 film spool.
The first step was to mark up the 120 paper backing to fit snugly into the Bolta spool (35mm). Like a 120 film spool the paper backing and film must be tightly wound to minimise chances of light leaks.
Starting from the first frame number (1) I measured 20mm either side of the number, making a total frame width of 40mm, and then added a further 2mm between frames. I continued marking 40mm wide frames with a 2mm gap between each frame for a total of 12 frames.
Approximately 50mm from the start of the first frame and 50mm from the end of the twelfth frame I marked the position of where I wanted the start of the film and the end of the film.
When rolling the film onto the backing paper I would tape the start of the film onto the paper at the film start then lay tape over the mark at the end of the film so that I could feel where the end of the film should be when working in the dark bag.
Using a permanent marker I marked the frame numbers 3mm from the bottom of each frame, from 1—12, at the top and bottom of the paper so that whichever way the film was rolled it would appear in the right direction in the window in the back of the camera.
Approximately 180mm from the ‘film start’ and ‘film end’ marks I cut the paper to allow enough paper to allow the film to be rolled without exposing the film (Note: next time I might cut this to 90mm as the completely rolled film was a little ‘fat’ and might not be light-tight.) The ends of each paper were cut to feed into the Bolsa spool.
Cutting the end of the frame square between the sprocket holes I taped the end of the film at the film start mark and fed the paper through the Bolta spool and taped it in place. It was time to move the spool to the dark bag.
Inside the dark bag I wound the paper and film onto the spool, pulling on it occasionally to make sure it was tightly wound. When I felt the tape marking the end of the spool I cut the film between the sprockets and taped it in place.
And there it is … a 12 exposure cassette of Konica VX100 (expired 2004) respooled onto a Bolta reel with reused XP2 backing paper.
There was 70mm of film left over. Not a bad calculation, but as mentioned I think that I need less paper backing before and after the film, as the spool looked a little ‘fat’.
Loading the film into the Ikko Sha I kept the spool tight and wound the paper forward with the film advance knob until it was tight. I then closed the latch and would the film (nervously) forward until the first number appeared in the window. The next post will be my experience with the Ikko Sha and expired 35mm film.
For an introduction to the Ikko Sha, see my first post here.