Suggest a place that can make some developing tubes

[Michael R]

In advance, yes, I know this is ridiculous etc. Now that that’s over with...

I’d like to try a variation on tubes-rolling-in-trays processing. Part of this involves a simple tube design I’ve thought about for a long time - picture a regular open tube but slightly barrel shaped (bowed out) instead of straight.

Since this would not be a daylight process (I don’t care if I’m in the dark), I’ve thought of a few ways of making (more like cobbling together) these myself. However that limits me in a few ways, including materials, so I’m wondering if I can outsource it.

Can anybody recommend a good machine/fabrication shop that could make something like this, either out of a plastic, or perhaps stainless? I have a few places so far, but really I have zero experience with this sort of thing.

Thanks

[Richard Wasserman]

Might you be willing to DIY the tubes? If both ends are open you could simply heat Plexiglass tubing in an oven to about 160 degrees Celsius and then apply gentle pressure to deform the tube. This would give you an oval tube-is that what you are looking for?

[seall]

What sort of sized tube?

Need more details...

[Michael R]

Richard - No I’d like them to be round all the way through. I’ve thought of a few ways of DYI-ing. We’ll see.

seall - These would be for 4x5 sheet film, so basically 5” in length. I haven’t decided exactly on the diameter but figure somewhere between 2” and 3” at each end, maybe 1/2” bigger in the middle.

Edit: I'm attaching two rough lengthwise sketches. The one with the curve is what I'd like, but there are potentially a few workarounds which might be more simple (see second attachment for example - a straight tube with a chopped off cone on each end).

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209731

[Oren Grad]

FWIW, in his Beyond the Zone System book, Phil Davis included an appendix with simple instructions on making tubes and caps from ABS or PVC plumbing pipe.

EDIT: OK, my bad. The barrel/cone thing hadn't sunk in.

I'll second the question: what would you like to accomplish with this? Maybe there are different ways of getting there.

[Alan9940]

Very curious to know why the tubes need to be barrel shaped?

[seall]

Michael,

It is not a difficuilt object to produce using something like Nylon 66 or Derlin but the material alone would cost upwards of £5-10 each if cutting from solid stock rod for 5x2", then there is the machining fee which would be a different level of cost altogether if it is just for a few items. Expensive if you want it made by CNC, cutting from thick walled tube would not reduce the overall price that much due to the high cost of automated cutting a few items. It may be a bit cheaper to get it done manually but time is money.

You could buy the material and find someone with a reasonable spec metalwork lathe to make the items and pay them by the hour, you may need longer bits of material though depending upon how the person doing this wanted to cut them.

Making it out of stainless is not a problem but you will likely find it to be a bit too expensive, unless you have a specific reason to use such a material. If you do want to use such a material you have different grades to choose from, you can even get it it with a certificate if you need such stuff - and have the money.

Any good machine shop will be able to advise you on making it and should be happy enough to speak to you about it but do take along a drawing with a 1. Front Elevation, 2 Side Elevation and 3. Plan with some part of the drawing showing a cross-section of the item along with any radius and taper sizes and the material you want it made out of. Then you can talk to them and your plan will be ammended there and then if needed. This makes it easier for them to give you a quote and you leave knowing a whole lot more even if you have decided not go get it made.

I would go with what Oren suggested then spend the extra money on film, that's if I didn't use the Jobo 2509n spirals which I have never had a problem with.

[DHodson]

Not sure if I understand exactly so sorry if I'm off base with this. I wanted some 4x5 tubes that held a bit more developer than the BTZS tubes handled so I made up some with ABS. Here's the thread for the earlier post.

https://www.largeformatphotography.info/forum/showthread.php?138107-ABS-Film-Development-Tubes-How-to-separate&p=1384248#post1384248

Good luck
Dave

[John Kasaian]

In advance, yes, I know this is ridiculous etc. Now that that’s over with...

I’d like to try a variation on tubes-rolling-in-trays processing. Part of this involves a simple tube design I’ve thought about for a long time - picture a regular open tube but slightly barrel shaped (bowed out) instead of straight.

Since this would not be a daylight process (I don’t care if I’m in the dark), I’ve thought of a few ways of making (more like cobbling together) these myself. However that limits me in a few ways, including materials, so I’m wondering if I can outsource it.

Can anybody recommend a good machine/fabrication shop that could make something like this, either out of a plastic, or perhaps stainless? I have a few places so far, but really I have zero experience with this sort of thing.

Thanks

Find a store like TAP Plastics.
https://www.tapplastics.com/about/locations
I'm sure there's got to be something similar in Canada.
They can do amazing things with acrylic and were reasonably priced the last time I looked.

[jim_jm]

Like Dave mentioned, it's easy (and inexpensive) to make your own tubes from ABS pipe, caps and adapters from the hardware store.
I bought 4x5 tubes from BTZS several years ago and have been happy with them, but did not want to spend the money for tubes to handle 5x7 and 8x10 once I made the move to those formats.
One advantage to straight tubes is that the developer will tend to flow evenly across the surface of the entire sheet as the tube is rotated in the water tray. If you have a barrel-shaped tube, the developer may tend to pool in the center of the tube during rotation due to centrifugal force, possibly affecting the even development of the sheet.

209732

[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 [emoji39] 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-garage-tools/funnel/flotool-flex-funnel-2-piece/52357_0_0?spps.s=3250&cmpid=LIA:US:EN:AD:NL:1000000:PER:71700000060668095&gclid=CjwKCAiA7939BRBMEiwA-hX5J-r0I74Pibu85z5XwfFKi0HArNd5cmE7FgeQKK1Yx_-vur-1f7PEaBoC_FgQAvD_BwE&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.209765

[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

[Oren Grad]

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).

A little tricky to measure, as the well narrows a bit a few millimeters down and it's difficult to get a ruler inside. Waving a ruler around just now and squinting at it sideways I'd estimate about 58mm inner diameter at the narrowing in the 3006 and about 66mm in the 3010. Of course that also doesn't allow for the barreling. Anyway, hope that's useful.

[Drew Wiley]

Ditto. Just get some short sections of dirt cheap ABS drainage pipe. But one thing others haven't mentioned is that you need to scrub them well before use, including the caps.
ABS manufacture involves mould release compounds containing sulfur, which will affect developers.

[Michael R]

Thanks, Oren. Those are good enough - I was just trying to get some rough numbers.

I didn’t know the cylinders/wells in the Expert drums were barrel-shaped, but I guess that makes sense. Looks like I’m partially re-inventing the wheel in this one, but it is interesting nonetheless.

Thanks again.

[Michael R]

Resurrecting this thread with some more questions about the Expert drums - working principles. Looking for people’s thoughts.

I’ve just acquired a 3010 drum. Putting some bits and pieces of info together (including minimum solution volumes), it seems like what is supposed to happen - assuming the drum is horizontal the entire time on a Jobo machine - is the solution collects in the lid in the empty space next to the cylinders/wells. As each cylinder rotates into the lowest position radially, it fills at least partially with solution, and then empties as it rotates upward again. How full each cylinder gets as it rotates into the lowest position would depend on the total solution volume, and possibly the rotation speed. There should always be some small amount of solution in each cylinder due to the slight barrel shape, but presumably the rest would always empty as the cylinder rotates upward from the lowest position.

Does this seem correct?

It is difficult to visualize what different solution volumes would look like (ie is the cylinder opening fully or partially submerged when it is in the lowest position? etc)

I am puzzled by the YouTube video posted by CatLABS of an Expert drum (3006) made of clear plastic (lid is black), demonstrating how it works. In that demo, it appears a significant volume of solution remains in most of the cylinders even as they rotate upward and around. How does that happen? And if that is what ends up happening, the development dynamics could be quite different than what I described above.

The reason I’m venturing down this hold is that I’m still trying to figure out if I can cobble together a small volume, manual contraption that essentially duplicates the way the Expert drum works in principle. We know the Expert drums on a Jobo machine are capable of producing excellent uniformity - probably the best. So I’m trying to figure out what actually goes on.