Suggest a place that can make some developing tubes

[Michael R]

Thanks everyone for the feedback, and to seall, John and Jim_jm for the extra information.

To Alan, Oren, Dave regarding the “why”... it’s nothing revolutionary (pardon the pun )...

I want to make a manual rotary processing contraption for my black and white 4x5 sheet film. In terms of throughput, I don’t need to be able to do more than 2-4 sheets at a time. Also, I’m used to processing in the dark and have never minded it so I don’t need this thing to be daylight-safe.

Picture two of these open-ended, slightly barrel-shaped tubes, side by side, roughly 1/3-1/2 submerged (horizontally) in a tray of solution, and rotating in a controlled way by some sort of hand crank. Each tube is just 5” in length. Easiest would be to have just one sheet in a tube, but I suppose a slightly wider tube with some divider “fins” could accommodate two sheets.

You move this mechanical assembly from tray to tray.

I imagine the rotation to be like a Jobo - ie say in the 50rpm range (but it could be whatever you want) and reversing every few revolutions.

I want the “tubes” to have this slightly bowed, barrel shape for two primary reasons:

1. The solutions get to the base side of the film, eliminating any potential issues with anti-halation dye

2. Minimal contact between the film and the tube means lower risk of scratching or weird contact artifacts

I considered a vertical variant of this, which might be easier to build, but that obviously means the tubes/film are fully submerged the entire time, and I don’t know if this type of rotary development would work. It would have to be carefully tested for uniformity.

[Oren Grad]

I want to make a manual rotary processing contraption for my black and white 4x5 sheet film. In terms of throughput, I don’t need to be able to do more than 2-4 sheets at a time. Also, I’m used to processing in the dark and have never minded it so I don’t need this thing to be daylight-safe.

Picture two of these open-ended, slightly barrel-shaped tubes, side by side, roughly 1/3-1/2 submerged (horizontally) in a tray of solution, and rotating in a controlled way by some sort of hand crank. Each tube is just 5” in length. Easiest would be to have just one sheet in a tube, but I suppose a slightly wider tube with some divider “fins” could accommodate two sheets.

You move this mechanical assembly from tray to tray.

I imagine the rotation to be like a Jobo - ie say in the 50rpm range (but it could be whatever you want) and reversing every few revolutions.

I want the “tubes” to have this slightly bowed, barrel shape for two primary reasons:

1. The solutions get to the base side of the film, eliminating any potential issues with anti-halation dye

2. Minimal contact between the film and the tube means lower risk of scratching or weird contact artifacts

I considered a vertical variant of this, which might be easier to build, but that obviously means the tubes/film are fully submerged the entire time, and I don’t know if this type of rotary development would work. It would have to be carefully tested for uniformity.

Got it, thanks. To the extent that you need custom machining of anything I suspect you will be at high risk of spending more than it would cost to purchase a second-hand Jobo Expert drum and roller base, let alone one of the less expensive reel-based systems. But you'll find out one way or the other soon enough when you start asking for quotes.

If you don't mind using a separate clearing bath for any residual antihalation dye, the regular BTZS tubes and home-brew pipe-based tubes can work fine. Long ago when I was getting started with 8x10, I used a couple of early-vintage BTZS tubes in that size until I was able to get a Jobo processor with Expert drum.

[Michael R]

Thanks, Oren.

I am considering possibly going with an Expert drum, as that was the initial inspiration for the type of development I’m contemplating here.

I have read reports of people having success with an Expert drum on a simple manual or motorized roller base. It seems to me that could potentially be a little hit-and-miss though. There are two ways of dealing with fill/dump in that scenario. The first is to simply fill the tank in an upright position (the way you’d fill a typical daylight inversion tank), and then put it on the rollers. What seems risky to me about that is - how do you know each cylinder is getting roughly the same amount of solution? The second is to make a curved hose and pour while the drum is rotating on whatever base you use. I guess that’s ok since it essentially mimics what happens with a Jobo lift. I don’t know, it sounds a little clumsy and like ideally I’d need three hands.

Anyhow we’ll see. If building my contraption becomes expensive I’ll have to rethink.

[Alan9940]

Don't know for sure if chemistry would flow evenly into each tube with the Jobo Expert Drums, but if you saw their construction one might think it's pretty good in that regard in that chemistry flows into the drum via a central location in the lid, then hits a flat area the makes up the solid central part in between the individual film tubes. Hmm, sounds confusing writing this, but you'd see right away. Therefore, I could imagine the chemistry hitting this area and randomly flowing into each tube. Would one/two/? get more chemistry than another? Probably, but I know several photographers who use the Expert Drums on motor bases, DIY bases, and manually rolling without issue.

FWIW, I've used BTZS tubes and my own DIY tubes (both straight designs) for many, many years and have never had any issue with the anti-halation dye and/or other development artifacts. I know of one pretty famous photographer that uses a length of open tube and simply rolls a set back-n-forth (in the dark, of course) in each tray. I'm sure that if he had issues with this technique he'd use something else. Just sayin...

[Fred L]

if you have access to a lathe, I'd experiment with shaving out the centre to create the barrel shape. would depend on how much barrel you need as the walls will be thinner. Richard's idea of heating it up then expanding it was my first thought as well.

[Oslolens]

I suggest making them yourself. ABS bar, a lathe and a bit of youtube https://m.youtube.com/watch?v=ICXKoKTdNP0

Sent fra min SM-G975F via Tapatalk

[Oren Grad]

I have read reports of people having success with an Expert drum on a simple manual or motorized roller base. It seems to me that could potentially be a little hit-and-miss though. There are two ways of dealing with fill/dump in that scenario. The first is to simply fill the tank in an upright position (the way you’d fill a typical daylight inversion tank), and then put it on the rollers. What seems risky to me about that is - how do you know each cylinder is getting roughly the same amount of solution? The second is to make a curved hose and pour while the drum is rotating on whatever base you use. I guess that’s ok since it essentially mimics what happens with a Jobo lift. I don’t know, it sounds a little clumsy and like ideally I’d need three hands.

The way the Expert drums are designed, the individual "wells" are not sealed off from each other - there's room underneath the lid. So once you have the drum on its side and rotating, gravity does the job of assuring that each well ends up with a similar amount of solution, averaged over the rotation period. Also see Alan9940's comment about the lid design and the inward flow. So the issue is solely how quickly you can pour in the solutions relative to the overall development time before you flip the drum on its side and get it spinning. In this respect developer dilution/temperature combinations that need longer times work in your favor as the pour-in becomes a smaller proportion of the overall time, though in choosing a dilution one has to be careful to assure that there is adequate developer agent for the film surface area being developed. Anyway, the pour-in time is also an issue with manual pour-in-pour-out development with a roll-film tank - how quickly do you get it filled before you start the initial agitation? Re the pour-in-while-rotating scenario, I know there are people who do that with roller bases - I hope some can weigh in on the details of how they make it work.

[Alan9940]

In addition to Oren's great comments, if you use a pre-wet of water before pouring in the developer, this should help mitigate some of the overall pour-in time. If the emulsion is already saturated with water, it takes some amount of time for the developer to displace the water. Worth a try, anyway.

Also, if you'd like to fill the Expert Drum while rotating on a motor base you may want to look at funnels that have a long(ish) flexible hose. These are used (or, used to be in my younger days of car repair) for refilling motors with oil. Something like this:

https://www.autozone.com/shop-and-ga...E&gclsrc=aw.ds

[cowanw]

I use a large (8") funnel on a length of thick rigged slightly curved 3/4 inch clear plastic tubing like from hole depot. the open end fits loosely into the mouth of the Jobo drum which is turning on the motor base. (I prewet), then I pour half the expected amount of water in, then the correct amount of developer in the rest of the required amount of water. the funnel restricts the filling rate to about 20 sec time, over which many revolutions have occurred. Push the timer button and put the funnel down and pay attention to the drum so as it doesn't run off the motorized base.

[Michael R]

Thanks everyone. A 3010 or 3006 is on my list of options.

By the way, out of curiosity, can anyone let me know the approx. diameter of the opening of one of the developing cylinders in a 3006 and/or 3010 (3010 should be larger).

Thanks