RB67 Pro S help needed

[mark]

I have a Sinar Zoom 2 that malfunctioned and rolled some rolls of film all the way through instead of advancing to the first image and stopping. Stupid me allowed three rolls of protra 160 to do this. I assumed, wrongly I guess, that I can just use them through my RB just going backrard. Now I have a jammed roll of film in a motorized back that I can't seem to get out, plus, the lens is cocked the holder is only half cocked so now what do I do?

If I remove the back, open it, remove the film, then put it back on will this damage anything?

 

[shutterfinger]

I'm not familiar with the motorized back but, put the darkslide in, pull the battery, then remove the back from the camera. If the darkslide will not go in pull the battery, take the camera into a totally dark room, open the back, pull the insert out, and roll the film up and secure with tape or a rubber band.
READ psot 13 of https://www.photrio.com/forum/threads/curious-advance-120-roll-2-rounds.167612/
In p;ace of a 620 spool use a empty 120 spool.
Correct the lens mounting as needed, dry fire the body/lens combo to verify it is working in sync then reinstall the back then the battery.
If the battery cannot be removed from the back then turn its power switch OFF and leave it off until ready to load a roll of film.

 

[j-dogg]

I'm not familiar with the motorized back but, put the darkslide in, pull the battery, then remove the back from the camera. If the darkslide will not go in pull the battery, take the camera into a totally dark room, open the back, pull the insert out, and roll the film up and secure with tape or a rubber band.
READ psot 13 of https://www.photrio.com/forum/threads/curious-advance-120-roll-2-rounds.167612/
In p;ace of a 620 spool use a empty 120 spool.
Correct the lens mounting as needed, dry fire the body/lens combo to verify it is working in sync then reinstall the back then the battery.
If the battery cannot be removed from the back then turn its power switch OFF and leave it off until ready to load a roll of film.

What this guy said. Also invest in a cheap changing bag for field work. I had a Mamiya back go south on me in the field and saved the roll in a film changing bag, opened the film back and found the problem, fixed it in the field and loaded it with another roll. Changing bags can be had for cheap and I bet APUG sponsors got them

 

[mark]

Found the source of the jam Since the film is only taped on one side, the leader end, and meant to run in one direction, running the film backward causes the film to not advance evenly with the backing thus creating a jam from the bunched up film.

@shutterfinger When re-rolling the film back after a mess up such as happened with my Zoom 2, how do you ensure the film is flat on the backing? Since I sacrificed the roll I tried to re-spool the film and I could not get it on so it did not bunch up.. I followed the instructions as you wrote them Could it have been the fact that since it jammed, the film was not flat but somewhat malformed due to the tightness of being jammed? I thought I had it flattened but maybe not.

 

[shutterfinger]

Yes the film must be flat against the backing paper and pulled taught so its flat from the taped end. In your case it might be better to wind the film as it would be when run through a camera then reroll it keeping it taught to the spools.
120 film is 3.5 to 4 mil thick depending on brand and easily kinked.

 

[John51]

Respooling 620 has the same problem.

Starting with the film as a loose roll in your hand, roll it up tight onto a spool, taped end first. To respool again, you need to feel when the film starts and get it tucked in. It loves to curl round the backing paper the wrong way. Roll that spool tightly as well.

If you've rolled both spools tight enough, there won't be a much of a bump, if any, when you come to the taped end. If the bump is too large to roll properly, you can re position the tape.