Today I constructed an insert for the Jobo 3063 drum to hold 7x17 film and it seems to work well. I found a plastic shelf liner material at the Container Store in Denver: "Plast-O-Mat Ribbed Shelf Liner." It is smooth on one side and has ribs on the other -- about 3/16 inch apart. The material is 24 inches wide, more than enough to fit the 3063 drum. The ribs allow the solutions to flow behind the film.
I then attached "sew on snaps" that I got from a sewing store at the critical points to hold the 7x17 film in place. I didn't sew them in, but drilled a hole through the shelf liner, and snapped one side to the other. I used four snaps for each piece of film: two on one side, one on the other, and one at the back as a stop.
Finally, I attached each end of the shelf liner to itself with a one inch overlap using pop rivets to hold the assembly around the Jobo drum's inner circumference.
I tested the works by developing a extra exposure I made this morning. The film held in place throughout the process and the development seems to be even and satisfactory . I haven't printed the negative, and used an untested, sore thumb development time, so more work is in order, but it's encouraging.
A few comments, observations, and notes:
> I assembled this for one piece of film only, but I can add additional snaps so the assembly could hold three pieces of film.
> The snaps have a beveled edge that provides a place to slid the sheet of film under and hold the film in place.
> The snaps are brass with a black paint finish. If the black paint breaks down, I would remove the paint entirely, and just use a unfinished brass snaps, which should not be affected by processing chemicals. I had hoped to find a similar snap in plastic, but wasn't successful.
> I'm concerned about using the pop rivets as they are steel and would like to find something else. Any suggestions appreciated.
> Adding additional sheets of film could affect how this works, e.g., will the shelf liner support three sheets of film? I think it will be OK, but will not know until I get a chance to test the assembly with all three sheets.
A few pictures are included.
Any comments or suggestions are appreciated.