Non-horizontal drum with Jobo CPP-2 and lift
This is my first help request on this forum. I hope my question is not too trivial.
I am just beginning to develop film. I have no previous experience. I bought a second-hand Jobo CPP-2 with "lift" and a Jobo drum with for two 35mm films. This is the drum with the cog on the lid, to be used with the lift.
I am at the stage where I am simulating things with water. I mixed "chemicals" (water), I learned how to load (very old) film into tank in a "changing bag", and now I am practising (with water) with timings, lift operations etc.
Today for the first time I actually inserted the drum into the lift. It "clicked" with a strong but healthy noise, and the Jobo seems to do the right job in rotating the drum back and forth. Raising and lowering the lift seems to work fine.
My problem is: the drum, when in working (rotating) position, i.e. with the lift down, is not horizontal on the Jobo. If the machine is levelled, as it is, the drum is not. The base of it points somehow noticeably "upward".
I checked on YouTube to see if this was normal. It seems that every Jobo machine without lift maintain the drum in a perfectly horizontal position, while Jobo machines with a lift, like mine, maintain the drum with the base higher than the lid.
My situation is similar to the one depicted in this video:
You can see, since the first seconds, that the drum is not horizontal.
Actually I think in my case it might be worse. Even with the water on the upper (red) basin at its maximum level, the base of the drum is immersed in water by two or three millimetres.
This raises the question: how can this be right? If I develop two films in an inclined drum, the film near the lid is certainly going to receive more chemicals than the film near the base of the drum, and the two films will not receive an identical processing.
Is there anything I should do to level the drum? Am I worrying too much?
I would like not to open the chemicals (all sealed) if I have to "fix" the Jobo first.
Thanks for your help
Rome - Italy
There are 2 small rollers on the lift mechanism that can be moved back and forth the length of the lift rods. They also sit on the lift mechanism in 2 positions to adapt to the different size drums. These must be placed in the right position to hold the drum so that it is level. There is one position for 2000 series drums and another for 1000 series drums. If you don't use the right positions, then the drum that you are using can be tilted up or down.
yes I noticed the two roller positions. I had tried the broad one, but it was way broader than my drum (Jobo 1520) so the narrow position is the only one possible. The 1520 drum actually seems to need only a couple of rollers, being small.
The lift ends its descent toward the horizontal position over a black screw head. That seems strange to me. I thought maybe the screw is not the original one (and is a too thick one so that the lift cannot go down to the horizontal position) but there is another identical screw on the other side of the lift so those should be original screws.
Maybe there is some misalignment in the assembling of the lift.
Can please somebody with a CPP-2 and a lift confirm, or deny, that his lift "lands over" a black screw head when it descends to the horizontal position?
Or should I simply turn the screw so that it enters a bit more into its slot?
Thanks for any help, any beginning is full of doubts.
I am not sure what you mean. When lowered, my lift fits neatly into the trough and straddles the gears.
I know that with my cpe2+ w/ lift, when using the 1520 tank, i have to put in rollers that are not inserted into the little black holders. Also, on mine, there are two different places to insert the drum into the lift. They have to be selected with a little white switch. I'm not familiar with the cpp2, so i cant comment as to if yours has the same options. However, i do notice that my drum seems to be quite level when put into the processor.
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do you have any photos ? this would help us figure out your problem as I see no screws on my CPP-2. The only black screw thing I can see would be the cog gear but that shouldn't be a problem since the lift fits over it.
Also make sure the rollers are in contact with the black body of the drums and not the orange flange.
Thanks everybody, I think I can see the problem better.
The upper part of the CPP-2, which Jobo literature calls "tempering bath trough", has a "raised ridge molded" on it. If I understand well, the rail which supports the rollers, when in horizontal position (lift down), should exactly "sit" in correspondence to the "raised ridge" and so be horizontal if the tempering bath through is horizontal.
After careful inspection, I saw that what happens is that the "elbow" of the rail which supports the rollers, i.e. the part of the rails that bends and goes up toward the clogs, touches the red tempering bath through BEFORE horizontal position is reached.
The opposite part of the rail, away from the clogs, remains above the "raised ridge" instead of "matching" with it.
This suggests either the lift is "too low" or the tempering bath through is "too high". We are talking probably 1 or 2 millimetres.
I also noticed that one of the six screws that unite the red tempering bath through to the black "body" of the CPP is missing. This is the screw which is left, opposite the lift lever (left, further from the operator), and so the nearest to the drum.
I tried to see if one of the other 5 screws would fit, but it does not, the screw does not "bite" the plastic.
So I intend to do this tomorrow:
1) Dismount and re-mount the lift. Maybe it does not sit correctly in its position;
2) Try to fix the red stuff to the black stuff with some screw and bolt if possible.
If this does not work, and in absence of better advice, I might gently scrape off some plastic from below the "elbow" of the lift rail and/or from the top of the red plastic. This will let the lift complete its motion and sit correctly.
The black screws I was referring to are the plastic (I realize now they are plastic) screws that connect the lift to the motor block. I screwed them well inside and now I see that what stops the motion of the lift downward is not the left screw (lift arm side), but the red tempering bath through, as outlined above.
I suppose the problem is not only mine. I read somewhere in Jobo technical documentation a few minutes ago that it is the drum in any case that must be levelled, not the Jobo (quite a strange assertion, as the drum should be levelled when the Jobo is).
Also, judging from YouTube videos, this should be a fairly common problem.
I intend to solve it anyway, with one of the methods above. I will let you know the outcome. Please do suggest better remedies if you know any.
PS Yes the rollers are in contact with the black body of the drum. The drum, I see, sits correctly on the rollers. The problem is that the parallel "rails" where the rollers are mounted are never horizontal.
Last edited by Diapositivo; 10-18-2010 at 08:02 PM. Click to view previous post history.
I have an idea what MIGHT be your problem Fabrizio.
Does the trough fit UNDER the small black plastic lip of the main unit near the lift ? This is a small lip, maybe 4 or 5mm and protrudes from the housing that holds the controls for the CPP-2. The lift shouldn't be a problem since it sits flat but if the trough sits on this lip, it could raise it enough to keep the lift elbow from dropping fully.
Also, the screws that attach the trough to the bottom section don't screw in to plastic on mine but into small metal retaining clips on the underside of the trough.
Canuhead, I checked the black plastic lip and yes, it is over the red through. On the other side of the lift I have some kind of a water drain (of unknown function to me) so I cannot place the red through over the black lip.
I dismounted the red through and saw the metal retaining clips you mentioned, I removed and put it where I needed it most, near the drum. I also dismounted the lift, cleaned the slot on the back (there was some kind of mastic) and reinstalled the lift. The lift still contacted the red through with its "elbow" so I rasped a bit the plastic under the elbow.
After this the problem was that the "raised ridge" further from the lift conflicted with the plastic part of the "binary" of the lift, the plastic was not correctly cast and it had several small dents that prevented the "raised ridge" to enter "inside" the corresponding black part on the binary. I rasped where I had to, and now the lift "potentially" sits where it should.
I say "potentially" because now the situation is this: when I lower the lift, the contact with the red through happens at the far end of the binary (good) but one moment after the binary raises itself by a few millimetres. I can push it with my finger so that it is adherent to the red through, but as soon as I lift my finger the tip of the binary also raises a bit, "elastically".
I suppose this is a sufficient degree of levelling when using a small drum like the 1520 but it could be less than optimal if using a bigger drum.
I would be grateful if you related on whether you observe the same "elastic" behaviour with your CPP-2 and lift on the far end of the binary. Does the far end of the lift go down (around 0.5 cm, 0.2 in) when you put your finger on it, and then up again when you take your finger away?
Thanks a lot for your attention and help
Well, no answers, so I suppose everybody else has the half centimetre of space between the through and the extremity of the lift.