Using Expert Drums without the processor

[Doc W]

I have been using Jobo Expert Drums for 8x10 and 5x7, and I just got another for 4x5. I don't have a processor so I have simply been rolling the drum back and forth in my darkroom sink (which is empty). I have been thinking that for longer development times in particular, the temperature of the developer could change more than I would like. I tried letting the drum float in a water bath, but it seems to take on a bit of water, not in the development tubes but in the drum itself, through slits in the bottom. I have never used an Expert Drum with a processor but I am assuming this has some purpose. In any case, it makes rolling the drum a little wonky. Also, water could easily leak in the top, so this method clearly is not going to work.

Have any of you had similar questions about using the drum without the processor? How do you use your Expert Drum?

Should we call ourselves, collectively, the Drum Corps?

 

[David Grenet]

I use mine on an ilford rotary base. The reason for the slits at the bottom is so a water tempering bath will be around the individual film tubes to maintain a more consistent temperature. My 3010 is actually missing the base completely which doesn't matter in the slightest for normal use.

 

[John Koehrer]

If you would like to build one a simple plank/plywood piece with four cabinet/chair(~1 1/2") rollers installed would allow you to roll it on a counter top.

Rollers facing up please.

 

[Photo Engineer]

There is more to it than that. Look at the base of the expert drum and you will see that it has holes in it. They are there so that the tempering water in the Jobo tank gets inside and circulates around the cylinders into which the film and paper are placed. This makes them very heavy, and you need to drain them before you take them out of the Jobo tank. Or you must replace the lost tempering water.

PE

 

[Doc W]

If you would like to build one a simple plank/plywood piece with four cabinet/chair(~1 1/2") rollers installed would allow you to roll it on a counter top.

Rollers facing up please.

John, have you done this? Would you have a pic?

 

[Doc W]

There is more to it than that. Look at the base of the expert drum and you will see that it has holes in it. They are there so that the tempering water in the Jobo tank gets inside and circulates around the cylinders into which the film and paper are placed. This makes them very heavy, and you need to drain them before you take them out of the Jobo tank. Or you must replace the lost tempering water.

PE

Thanks for this reply. Here is another question. As I said, I have been hand rolling with worrying too much about temperature, other than to make sure that my developer is spot on before pouring it in. I have been assuming that the temperature of the developer in the drum will not change too much over the course of processing. But recently I have been using longer developing times and I am pretty sure the temperature of the developer in the drum will rise of fall slightly. Has anyone tried to use the drum on a roller base in a water bath? I am guess it would have to be pretty shallow so the drum won't float. I wonder if, with a roller base, I could get at least some of the water bath to trickle into the drum to circulate around the cylinders.

I hope these question are not too weird. I love using the drums but I just can't afford a CPA or CPP processor.

 

[Vaughn]

I run my 3005's on a Beseler motor base...with auto reversing disengaged. I pick up and manually reverse the drum every minute.

If you have a steady ambient temp, then for your longer development times, you might raise the developer temp a little and assume that the temp drop will be consistent. Results should be repeatable.

Method #2 -- always develop at room temperature, adjusting the time for warmer/colder days (or keep the room at a constant temp).

 

[eclarke]

Thanks for this reply. Here is another question. As I said, I have been hand rolling with worrying too much about temperature, other than to make sure that my developer is spot on before pouring it in. I have been assuming that the temperature of the developer in the drum will not change too much over the course of processing. But recently I have been using longer developing times and I am pretty sure the temperature of the developer in the drum will rise of fall slightly. Has anyone tried to use the drum on a roller base in a water bath? I am guess it would have to be pretty shallow so the drum won't float. I wonder if, with a roller base, I could get at least some of the water bath to trickle into the drum to circulate around the cylinders.

I hope these question are not too weird. I love using the drums but I just can't afford a CPA or CPP processor.

Just for fun, Fill a container with water at the temerature you desire, put a thermometer in it and watch it fo a while to see how much it actually changes..could be a surprise..

 

[Photo Engineer]

Doc, there is a thread here, probably a sticky, in which someone tested a 100F process both with and without a prewet with water at 100F. He noted the drop in temperature as described above. I think the poster was Greg Davis.

PE

 

[Doc W]

I just developed a few test sheets for 8 minutes. The temperature in the darkroom was about 19C/66F. The developer was exactly 20C/68F when I started and it was around 22C/72F when I dumped it! I was not expecting it to go up.

The temperature in my darkroom changes quite a bit seasonally so I guess I am going to have to come up with some kind of temperature control solution. I see a lot of plywood and epoxy in my future since I do not have the do-re-mi for a CPA or CPP.

 

[DREW WILEY]

No big deal. You could simply roll one back and forth in a darkroom sink. A simple insert like a trough could serve as the tempering bath.

 

[Barry S]

I use a Jobo CPA-2 to process my film in Expert drums and although I find it very useful, using a simple rotary base works perfectly well with black and white film. I used to mix and process everything at ambient temperature and used a time/temperature compensation chart to adjust the processing times. See http://www.digitaltruth.com/devchart.php?doc=timetemp Unless you have wild ambient temperature swings in your darkroom, you might not even have to adjust the times. Small variations in dmax and contrast are easy to work with using normal variable contrast papers.

 

[Photo Engineer]

If you use a Jobo-Expert drum combination and the serial number of the Jobo unit is in a low range (I don't have that figure-sorry), then you risk burning out the motor or breaking the lift due to the weight of the 3000 series drums. The early Jobo units were not designed for the weight.

PE

 

[John Koehrer]

John, have you done this? Would you have a pic?

I haven't done it but Jobo made a similar unit once upon a time. Their unit used two rods with each pair of rollers mounted on a common body.
The entire thing sat on a table top with no additional support. Because it's plastic it could be set into a water bath too. One could also be made with acrylic as a base if you're in a DIY mood.
Further thinking has me going to a simple frame with rollers mounted. That wouldn't take much material at all. How about some aluminum picture frame with the rollers?
See why I try not to think about this stuff too much?

I haven't looked but the auction site may have something. Additionally some image may be online. under "Jobo Roller" It's catalog # is 1509

 

[Photo Engineer]

The Jobo "roller extension set" was also used to extend the rollers on processors to use with long extended tanks. It offered support for those long tanks.

I used them for 16x20 or larger.

PE

 

[Doc W]

I have been experimenting and I think I have come up with a solution. I filled my darkroom sink with water at 20C. It is a decent size sink but I did not fill it too deep. I then put in a 16x20 tray and filled it with just enough water (also at 20C) to allow the drum to take on some water. It floated at first but as soon as water came in it settled down nicely. I was able to hand roll the drum quite easily. I developed several sheets of 5x7, at 6, 8, and 10 minutes, and checked the temperature of the developer after each. In each case, it was still within a half degree of 20C.

The only problem is that the technique is a little messy. When I roll the drum away from me, there is no problem, but when I roll it toward me, water tends to fly off the top (mostly from my hands) and I get a little wet. Quite wet. Looks like I wet my pants. The next step is to try to secure a piece of plastic on the front side that is slightly higher, to cut down on this spray.

I think that eventually, I will build something to replace the tray and add an aquarium thermometer to keep the temp constant when my darkroom is colder (and it can get quite cool in the winter).