120 Rolls Slipping in Jobo Reels

[mercurye]

Hi all,

I usually develop 2 rolls per reel in the Jobo reels in a Multitank 5 with ATL-1000, using the red clip to separate them. Usually after developing the reels and taking the film out, I will find them over-lapped, (but both developed properly), ostensibly from the constant cyclical motion of the tank. However, I believe due to the new Kodak film base--which is thinner--I've just now had a roll overlap and stick together when dry, preventing the entire roll from developing properly. I was wondering if anyone else has had this problem, and if there is a way to prevent it.

 

[ic-racer]

Are you sure the first roll of film is pushed all the way to the center and stops before engaging the red clip?

 

[pentaxuser]

How much thinner is it? I'd be surprised if it is enough to give you the loading problem you seem to have. ic-racer may have made a valuable suggestion in terms of where to check first

pentaxuser

 

[Neal]

I have had times where the spiral part of the Jobo reel became misaligned with the hub and can imagine where such a situation would allow film to slip past the pin. Since I started ensuring proper alignment before loading the problem has not recurred. (Of course, this might have nothing to do with your issue.)

 

[MattKing]

I expect that the change in substrate would result in a change in how "slippery" the wet film is - in my experience with non-JOBO reels that is the factor that creates most of the difficulties.

 

[pentaxuser]

I expect that the change in substrate would result in a change in how "slippery" the wet film is - in my experience with non-JOBO reels that is the factor that creates most of the difficulties.

Assuming the OP loads the film "dry" so no wet film on loading, does the above mean that once processed and thus wet, the substrate will allow the film to do what it has done with non Jobo reels only? However as he has Jobo reels can he exclude this as the answer? If so, I don't understand the significance of your post to the OP's problem

pentaxuser

 

[MattKing]

As I understand it, the OP was doing this successfully before with film on an acetate base, but is having problems with the new films on a polyester/Estar substrate.
So I expect that the change in substrate is causing the film to behave differently in the reels.
I doubt that the reels were designed with the new substrate in mind - it basically wasn't used for any roll films back then.

 

[mercurye]

Are you sure the first roll of film is pushed all the way to the center and stops before engaging the red clip?

Yes, it is fully pushed in, and film at the end

As I understand it, the OP was doing this successfully before with film on an acetate base, but is having problems with the new films on a polyester/Estar substrate.
So I expect that the change in substrate is causing the film to behave differently in the reels.
I doubt that the reels were designed with the new substrate in mind - it basically wasn't used for any roll films back then.

Yes, I have developed probably 400+ rolls without issue. The new thinner base with Kodak color films makes it very easy to load onto the reels, but I suspect it thickness might also somehow allow it to slip past the clips? I'll probably try pre-wetting the film after loading and before putting it on the cog-head, and see if that prevents movement. I was just curious if anyone else has had this issue

 

[Don_ih]

I'd stop loading two strips on a reel. Use two reels? You could fold the very end of the film strip over to double its thickness. And fold over the start of the next strip. Those two folds butted together won't let the film overlap.

I often develop short (10") strips of 120 in a jobo. I fold over the trailing end of it to "lock" onto the start of the spiral.

 

[pentaxuser]

So it looks like the new substrate mean that even with the red separators the film will slip over another film in the same reel and users will have to either load one film only or tape the two films together

Seems a pity but that's progress for you

pentaxuser

 

[MattKing]

Films have changed in the 30 - 50 years since those red tabs were designed.
Perhaps the tabs need updating.
I wonder if a fold of tape added to the trailing end of the first film, along with a fold of the existing tape at the leading end of the second film would work?

 

[d_kolobov]

I also encountered two films sticking together, which resulted in the loss of one frame. I really didn't like it. Over time, I became more careful about checking separating clamp, and I almost always load the second film with the backing side up. This prevents sticking even if you don't use separating clamp.