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View Full Version : Achilles' Arm -or- The Curse of the Jobo Lift



Oren Grad
25-Aug-2005, 19:40
Well, the inevitable happened this evening - the arm broke off my Jobo Lift in the middle of a processing run with the big 3005 drum. Fortunately, it was during the wash phase, and the film came out fine.

I'll call OmegaSatter tomorrow to see whether they have replacement parts in stock yet as they accept the distribution handover from Jobo USA. Meanwhile, the design of this plastic part seems so inherently flawed that I have to wonder - has anyone ever tried to have a machine shop make an all-metal lift arm? Or some kind of bracket that would allow lifting the drum by grabbing the rails underneath?

John Flavell
25-Aug-2005, 19:48
We once used a JOBO for processing transparancy film. Our solution to the problem was to take the Jobo up to the roof and drop it three stories into the huge garbage can out behind the building.

Paul Butzi
25-Aug-2005, 19:50
Someone, I don't remember who, made a handle they called 'lift-assist' or something along those lines. It was a handle that attached to the rails at the end away from the pivot, allowing you to lift the drum and rails by grabbing the handle and swinging it up.

Not very helpful, I know, but at least it lets you know that someone has tried that and found it to be a marketable solution.

Donald Hutton
25-Aug-2005, 19:53
Where did it break? - I have broken the end of the handle before and now just always use my right hand to help the lifting of big drums. I would try the number for Jobo in Ann Arbor - there were still a few folks in there two weeks ago.

Oren Grad
25-Aug-2005, 20:09
It broke right at the base of the arm, at the point where it joins the round base part that screws into the body of the lift. I could epoxy it back together, but even if it holds I suspect the plastic will just fracture somewhere else.

I've always used my hand to help the lift, but I still needed to use the handle just to get the tank up an inch or so to leave room for me to grab the rails underneath. In the end that, alas, was enough stress to do the trick.

Grrrrrrrrrrrrrrrrrrrrrrrr... The wise thing would have been to order a replacement arm a long time ago to have on hand, since it was obvious this was going to happen. Oh, well. The Jobo USA website says the official handover was earlier this week, so I'll try OmegaSatter tomorrow and see what they have to say. But I'd still be happy to hear of any ideas for a more robust substitute part, since the replacement is bound to break eventually too.

Donald Hutton
25-Aug-2005, 20:14
I've broken that horrible little thing - it's about $5 for a replacement and takes all of 5 seconds to instal, if you can get one! You should easily be able to drill a little pilot into each end of the break and epoxy a little steel pin in there - should work just fine until Omega get set up. FWIW, I have had very good service from Omega Satter in he past. It is definitely a stressed point on the lift, but I would guess that a new one should be good for a couple of years...

David R Munson
25-Aug-2005, 20:21
Where did it break?



In the darkroom! *rimshot* (my apologies - I couldn't resist)

Michael Kadillak
25-Aug-2005, 20:39
Mine broke a couple of years ago and I went ahead and ordered the replacement. After using it without the arm with my expert drums for the time it took to arrive, I left the replacement in the darkroom drawer. It is completely unnecessary and a complete waste ot time. If you have to you can use both arms to grab a hold under the drive mechanism to empty.

Even if you could machine a metal one, you would only be moving the design flaw to the next weak point - the plastic pivot.

Cheers!

ronald moravec
25-Aug-2005, 21:05
I always, from day one, pick up the rails with my right hand. It just seemed flimsey to me.

I also break the vise grip jaws that hold the cog lid with a stem from an old thermometer. I have not gotten a broken plastic gripper since. Just release the right or rear one while pulling the drum towards yourself. The remaining one releases without the loud snap.

For the cost, it could be better engineered.

It`s use is limited to 4x5 color neg in the expert drum now so it is semi-retired. Black and white goes in the 4x5 Nikor tank or on hangars, hangar rack, and sink line.

Get a NOVA slot processor for color prints.

Oren Grad
25-Aug-2005, 21:41
Thanks all, for the various comments.

Paul - sounds like a good idea. I was able to find just one trace of such a thing on the web - a single PN message posted by Spiros Polemis in 2002, about a "Jobo Lift Helper", said to be "from an outfit in San Diego".

Don - thanks for the steel pin suggestion. I have a bit of trouble handling a drill just now, but will keep that in mind.

David - minus two points for that one. ;-)

Michael - I'll do a bit of fiddling over the weekend to see whether I can get comfortable with just grabbing the rails. I think I need thinner fingers, but if it comes to that, I'll find a way to make it work, because the advantages of the Jobo overall are just too great. My thought re machining a replacement part would be for a single part that includes the hub that screws into the lift body. No doubt it would be frightfully expensive to get a single piece like that fabricated. The same Google search that turned up Spiros Polemis' posting also turned up a message on the alt-photo-process list by William Laven, who may have done just that.

Ronald - I use my CPA-2 strictly for B&W sheet film, in sizes from really small to really large.

tor kviljo
26-Aug-2005, 00:46
One of the best thing about a JOBO ATL 2xxx - 3000 over the CPP or CPA You have is that there is no lift to go ###?%¤&!!. In the latter years, I have seen quite a few of the big ATL's going for not much more than the CPP/CPA's on german & US ebay, so if You use the expert drums a lot (which is not to be inverted using lift handle only), investing in the comfort of a ATL 2xxx/3000 is no bad idea. I have an old & battered ATL 3000, have never let me down & I can load it with chemistry for 5 dev's in a row (1.8l) - very far from the fuss of a CPP/CPA .

Calamity Jane
26-Aug-2005, 03:45
Oh oh! This isn't the kind of thing I like to hear :-(

With the addition of 8x10 to my stable of cameras and a burning desire to see an 8x10 E-6, I bought a CPA-2 from a very nice gentleman (and forum member) which is now sitting just across the border waiting for me to pick it up.

Being employed in the design field and notorious for re-designing things, I can see I will have to have a very careful and critical look at the lift mechanism. If it is a chronic weakeness, there must be a way to beef it up.

Thanks for the heads-up guys! I'd hate to have got caught part way thru an E-6 run with a busted processor.

John Cook
26-Aug-2005, 05:14
Perhaps this new gizmo from Shopsmith will give you tinkerers some ideas:

http://www.shopsmith.com/ownersite/catalog/mvmisc_liftassist.htm

Unfortunately, I can tell you from personal experience that it operates properly only when you are wearing a plaid flannel shirt. "Dress Stewart" is the preferred tartan.

Larry Gebhardt
26-Aug-2005, 06:29
Oren, if you can't get the part right away let me know. I have a new spare that I could loan you until you can locate another.

Oren Grad
26-Aug-2005, 07:41
OK, just spoke with OmegaSatter. The good news is, they knew what I was talking about. The bad news is, everything is still in limbo - Jobo has closed up the analog shop in Ann Arbor, but OmegaSatter isn't up and running on Jobo gear quite yet. They promised to call back with more info as soon as they could.

Tor, an ATL 2xxx would be marvelous, but I don't think my darkroom can accommodate one at this point. The space is small enough that I need to be able to move things around, and the ATL is far more weight than I can handle on my own.

CJ - at the very least, you want to minimize the strain on the handle by supporting the rails from underneath with your hand as much as possible when you're lifting the tank. I don't know what, if any, are the weaknesses of the mechanism within the housing, but the handle is a lightweight plastic and is notorious for its fragility. You're really good with mechanical stuff, so I'll be very interested to hear if you come up with any ideas on this, either with respect to the handle itself, or an easy way of rigging a "grabber" to lift the tank by the rails without interfering with its rotation. Note that the handle serves two functions - one is to lift the tank, but the other is to perch under a little protrusion on the Lift body so that the tank can sit in draining position without the user having to hold it up. So even if you come up with some sort of rail grabber, it's still an advantage to have a handle that's at least solid enough to support the tank in draining position, even if it can't withstand the jerk needed to pull the tank up after each processing step.

Larry - that's very kind of you. I'm a little nervous about taking you up on it until I know for sure that OmegaSatter will be able to supply a replacement sooner or later - I'd be afraid of breaking yours and not being able to replace it. Let's see what OS is able to come up with.

Bruce Watson
26-Aug-2005, 07:50
Oren,

The simple answer is, don't be afraid to get your hand wet. Lift the assembly from the bottom. That is, stick your hand in the tempering bath under the tank and lift the arm that supports the tank. Forget the handle.

This is far easier on the lift as it puts the strain of lifting a full tank on you, not it. Yet is still gets what's best out of the lift which is the control and easy drain/fill.

I've been doing this with a CPP-2, 3010 drum, and one liter of chemistry for years now with no trouble.

Oren Grad
26-Aug-2005, 08:15
Bruce, it's really easy to grab the end of the rail assembly when using one of the shorter drums, like the 3006 or 3010. But the longer drums, like the 3005, extend way beyond the end of the rails. The 3-series drums are so fat that my hands can't get in from the sides, except at the lid end, but that too is far from ideal mechanically - it puts a lot of force where it wasn't intended, and it's hard to grab the rails and pick up the tank cleanly without grinding the cogs, also not a good thing.

Michael, exactly where are you grabbing when you lift one of the big drums?

Donald Hutton
26-Aug-2005, 08:59
Oren - just stop the motor before you lift and grab the end of the tank and help it up...

Yong-ran Zhu
26-Aug-2005, 10:02
The arm is not designed for lift the drum. It just helps you to disconnect the motor. You have to use your right hand to lift the rail from the water bath and pour the solution out from the drum. You don't need to stop the motor.
Yong-ran Zhu

Tom Westbrook
26-Aug-2005, 10:03
...but the other is to perch under a little protrusion on the Lift body so that the tank can sit in draining position without the user having to hold it up.

That's interesting. I don't think my lift has that feature. I bought a new lift for my used CPP2 about a two years ago. Maybe they ditched the perch idea because it caused too much stress?

I had no idea Jobo USA was closing. Too bad. I always got great service from them.

Oren Grad
26-Aug-2005, 10:42
I should jump in here and respond to Tom's post immediately, to make sure I don't send someone astray. I've been doing more homework on this, and it has become apparent that in that respect I was most likely misusing the equipment. Jobo recommends using the protrusion only as a stop, not as a "perch". It's possible that in pulling the handle beyond and using the protrusion as a retainer to hold the tank up I put the handle under even more stress than the tank load alone should have caused, and in that way accelerated its failure.

Meanwhile, still working on some fixes and workarounds...

Bruce Watson
26-Aug-2005, 14:23
If you can't reach the rail, put your right hand under the right side of the tank and lift the tank itself while your left hand rotates the lift lever. This takes the weight off the lift so you don't break it. YMMV; there are lots of ways to accomplish the same thing I'm sure.

Larry Gebhardt
26-Aug-2005, 14:36
Oren, I doubt I will need the part for some time. I usually use an ATL2000 and the CPA is only used for quick runs when I don't want to empty the ATL's bottles and do a clean. So if you need it I will be glad to send it to you.

Oren Grad
26-Aug-2005, 15:00
Larry - many thanks, I'll follow up via private email.

Craig Wactor
26-Aug-2005, 15:55
I've always thought those jobo arms were too flimsy. I broke one once too. Super glue didn't help. Just learned to live without it...

Calamity Jane
5-Sep-2005, 06:48
Has anyone had the lift mechanism break at a place OTHER than where the aluminum lever slips over the plastic "hub"?

I got my CPA-2 home last night (never seen one before!) and had a look at the lift. It might be easy to get that "hub" cast in aluminum since it is a fairly simple shape and would require very little machining. I expect I could do aluminum hubs for about $15 each to select customers ;-)

If they break somewhere else, there's no point making a stronger hub.

Thanks crew!

Oren Grad
5-Sep-2005, 07:10
CJ -

If you haven't already done so, take off the hub and look at the profile of the shaft that couples to the internal mechanism - it's not quite so simple.

They probably went with a plastic part for cost reasons. But there may also be an issue of wear to the internal part that the hub plugs into - if that's plastic, or some sort of soft metal, you might end up just transferring the point of vulnerability. But take a look and see what you think.

While you've got your thinking cap on, mount a 3005 drum and see whether you can envision a "lift assist" or "grabber" device that can latch on to the Lift rails and sit underneath the drum so that you can lift from the end of the rails, which would probably be the safest solution of all.

I'm looking into some custom-fabricated solutions myself. But if you can come up with a solution that's structurally sound and reasonably affordable, you'd have a tiny niche market all to yourself. ;-)

Cheers...

Calamity Jane
5-Sep-2005, 12:11
Oren,

I am thinking of a lost wax casting. For LWC, you need only make one female mould of the part. It can be quite complex as you never have to make another one. A description of the process can be found online.

Lost wax is more expensive than injection moulded plastic IF one is making LARGE quantities but an injection mould is worth $20,000 to over $100,000 depending on complexity. For small runs, LWC is more economical.

The only thing I don't like about a handle on the end of the roller assembly is the length of the arc. With my 3010 drum, that's a LONG swing! It would work and it would take the stress off of the lift arm and pivot but I am not sure it's necessary if the nub that holds the aluminum handle is the only problem with the present mechanics.

. . . just looking at possibilities . . .

polemis
18-Jun-2007, 05:29
CJ -

If you haven't already done so, take off the hub and look at the profile of the shaft that couples to the internal mechanism - it's not quite so simple.

They probably went with a plastic part for cost reasons. But there may also be an issue of wear to the internal part that the hub plugs into - if that's plastic, or some sort of soft metal, you might end up just transferring the point of vulnerability. But take a look and see what you think.

While you've got your thinking cap on, mount a 3005 drum and see whether you can envision a "lift assist" or "grabber" device that can latch on to the Lift rails and sit underneath the drum so that you can lift from the end of the rails, which would probably be the safest solution of all.

I'm looking into some custom-fabricated solutions myself. But if you can come up with a solution that's structurally sound and reasonably affordable, you'd have a tiny niche market all to yourself. ;-)

Cheers...

Hello, Oren, long time no see . . .

There was a company in the San Diego area who sold a stainless lift arm that attaches to the lift rails. works perfectly. you may try a web search for lift arm. I'll post a photo of mine within a day or two.

--Spiros