Tanks: they leak and they lose temperature. WHY?

[David Lyga]

Coca-Cola can make a leak proof bottle for about 2 cents. So can multitudes of other manufacturers. Why cannot there be a film tank that absolutely, really and truly does not leak even one drop?

And one that holds temperature like a Thermos?

Why are these questions so very esoteric and unimaginable to fathom?

The technology has existed for years. WHY NOT? - David Lyga

 

[sr44]

I often wonder the same thing. All of my development tanks leak horribly!

 

[benjiboy]

Coca-Cola can make a leak proof bottle for about 2 cents. So can multitudes of other manufacturers. Why cannot there be a film tank that absolutely, really and truly does not leak even one drop?

And one that holds temperature like a Thermos?

Why are these questions so very esoteric and unimaginable to fathom?

The technology has existed for years. WHY NOT? - David Lyga

Don't know David, where do all the flies go in Winter ?

 

[David Lyga]

There is laughably no reason. I really do not understand some things in life. Especially when they are so easily solved. Soft drink manufacturers have solved this for pennies but even if you pay $20 for a tank you can be assured that it will leak. Why am I the only one bringing this up?

The older I get the more I desperately cling to reality and common sense. And no, I do not require a Kindle to read a book. I jot pencil markings on a paper page.

The flies die, Ben, because it gets too cold. - David Lyga

 

[benjiboy]

It's a very good point David why hasn't anybody ever marketed an insulated developing tank that would retain the temperature like the stainless steel double walled insulated jug I have on my filter coffee machine that stays hot for hours ?

 

[bobwysiwyg]

I use the much maligned Combiplan with no leaks. I have say though, initially I did until I figured out the issue. You press the lid on thinking it is tight and secure, dribbles persisted. Because the lid is softer rubber it "grabs" a bit and doesn't really secure, water tight unless you apply a good deal of pressure all the way around. I do it by pressing the tank bottom to my chest, then working my fingers around the rim firmly press the lid against the rim of the tank. No leaks since and I do inversion agitation.

 

[Ken Nadvornick]

Single-walled stainless steel tanks are preferred precisely because of that thermally conductive property. That very characteristic is what makes precision temperature control in a tightly maintained water bath possible. Very low thermal inertia. Contained liquids respond very quickly to changes in external water bath temperatures.

In my own case I maintain water bath temperatures using a Hass Intellifaucet K250. Marvelous temperature control possible using this precision tool. In the winter I often set the Intellifaucet to, say, 68.4F to counteract the slight loss of solution temperatures resulting from the colder darkroom ambient air temperature. Single-walled stainless is what makes this possible.

What needs to be insulated is not the stainless steel processing tank (or tanks). It's the container holding the water bath in which they sit. That's the common reference point that you don't want to drift. I would never use plastic processing tanks. Too difficult to precisely adjust. Especially for color.

This particular behavior isn't a bug. It's a feature.

Ken

 

[Bill Burk]

Well, my Leonard valve isn't in the same technical marvel class as the Hass.

But I run a steady stream into a gallon-sized stainless steel mixing tank (think stock pot).

Then the (you are so right David Lyga) leaky Nikor tank gets immersed completely into the 68-degree F water... the temperature of the bath is monitored by the CompnTemp USB probe.

I have to wonder though why there aren't more double-wall vacuum tanks... Doesn't the ASA specification require a thermos bottle?

 

[MartinP]

The lid on my larger Jobo 1510+1530 tank leaks very slightly during inversions, but it is much older than the Paterson System 4 (the sort with a tupperware-like lid) which doesn't leak at all - and which is also much quicker to fill or empty. Happily I have not tried a steel tank to compare.

 

[Gerald C Koch]

I use a SS tank with a flexible plastic lid as originally made by Kindermann. They never leak. The SS tank and a water bath allow very precise temperature control.

 

[Bob-D659]

If you are doing C41, the dev mixing with an acidic stop or the bleach generated a LOT of CO2 gas, more than enough to pop a sealed lid off a tank.

 

[MattKing]

If you are doing C41, the dev mixing with an acidic stop or the bleach generated a LOT of CO2 gas, more than enough to pop a sealed lid off a tank.

Even garden variety fixer like Ilford Hypam tends to want to release some gas.

And David, a $20.00 tank is a cheap one indeed!

 

[pentaxuser]

Try Durst tanks. Mine leaks not a drop but filling and emptying takes a little longer than my Jobos which with vigorous inversion will leak slightly but not enough to make a difference to the safety margin that Jobo builds in when it tells you to use 240 mls for 35mm and I fill to 250 mls becasue it is an easier number

pentaxuser

 

[paladin1420]

It took me a while to get used to the stainless steel reels and tanks. Now that I am I like them so much better than using plastic because:
1-Now that I have the hang of it, I can load the SS reels faster and more easily than the plastic. I've also never had a steel reel pop open and spring the film loose
2-Since I started processing C-41, the temperature control of the steel is very convenient.
3-They use less chemical (580 ml in the Paterson vs. 440 ml in the SS for 2 35mm rolls)
4-The steel reels and tanks are easier to dry and can still be used without trouble even if not perfectly dry. Not so the plastic.

I have a single real SS tank that does not leak, although the steel cap is sometimes a challenge to get off in time critical spots when changing chemicals.

A Question:
The plastic lid on my double reel SS tank has a crack in it and leaks, does anyone know if these can be replaced?

 

[E. von Hoegh]

I use SS Nikor tanks exclusively for 35mm to 4x5 sheets. Tempering bath for C-41 and E-6. Never had a problem with drips, never had trouble maintaining temperature.

Some "problems" are problems only if you want them to be.

 

[removed account4]

even my yankee hand tank that has a crack in the side
from overzealous d-bubbling doesn't leak ...
unicolor drums, well ....

 

[David Brown]

A Question:
The plastic lid on my double reel SS tank has a crack in it and leaks, does anyone know if these can be replaced?

Yes. They should be readily available.

http://www.bhphotovideo.com/c/product/122992-REG/Samigon_ESA359_Plastic_Cover_for_all.html

 

[paladin1420]

Yes. They should be readily available.

http://www.bhphotovideo.com/c/product/122992-REG/Samigon_ESA359_Plastic_Cover_for_all.html

Thanks for that. I didn't think to check, I had assumed you needed to buy everything new. I suppose they all must be a standard size.

 

[average-guy]

I use a SS tank with a flexible plastic lid as originally made by Kindermann. They never leak. The SS tank and a water bath allow very precise temperature control.

I second that, I use the same tank. If it leaks, it's because I didn't make sure the lid was pressed down all the way, which is in no way the fault of the tank.

 

[bvy]

If you are doing C41, the dev mixing with an acidic stop or the bleach generated a LOT of CO2 gas, more than enough to pop a sealed lid off a tank.

I use Paterson tanks and actually twirl agitate the bleach and fix steps with the tank sitting in a tempered water bath (in a small Playmate cooler). This has been working well for me.

 

[David Lyga]

Bob D659 does, indeed, bring up a valid point in that the development process does release gas. But, so does carbonated soda. That is why there had to be a truly leak proof container made for soda. Enough did not 'complain' that the same should have been done for 'mere' darkroom nuts.

And, Ken Nadvornick, there is a valid point here about the desirability of using a material such a stainless steel that AIDS in conducting temperature (ie, water bath). But, still, there are some who would like a truly leak free tank.

And Gerald C Koch, I am not saying that you are wrong with your SS tank with plastic top being entirely leak free, but I would like to put it dry upon a towel, without your water bath, and see it stay dry. I have my doubts but it might be as you say. In a water bath you would never notice a leak. And you could not prove this by merely putting food coloring in water to see if any color came out into the water bath. As I just confirmed Bob D659: there is a pressure build up that 'forces' leaks in the development process. - David Lyga

 

[octofish]

Not sure that a well insulated tank would be that useful. Unless you temper it very accurately - which is a pain to do - you will get a temperature change when you put chems in anyway. Tempering will be impossible from the outside (it's not even all that feasible using a normal plastic tank - takes too long), which pretty much means you need to prewet whether you want to or not.

The other option is estimating the expected temperature change, which is necessarily uncertain. You can always measure inside the tank with a thermometer to work out where you are, but then if you are wrong, how do you get the tank temperature to where it needs to be, if the tank is well insulated? A water bath will be ineffective.

Also I believe some proceses (fixing?) result in a bit of a temperature change by their nature, in which case you're stuck where you end up as a result of that. Could be wrong about that though.

Of course, this is all if you care about that level of precision. If you don't, then a plastic tank is pretty much good enough anyway.

 

[MattKing]

It occurs to me that very few in the beverage bottling industry see much need for a bottle that is both light tight and enables rapid dumping and filling of liquids.

So I'm not sure that is a great source of comparison.

 

[eddie]

It occurs to me that very few in the beverage bottling industry see much need for a bottle that is both light tight and enables rapid dumping and filling of liquids.

They also need to open and close only about 5-6 times. And, they only have one cap. A developing tank has two.

I would like to see a stainless tank with deep screw top threads, on both lids. Kinda like my martini shaker...

 

[albada]

A Question:
The plastic lid on my double reel SS tank has a crack in it and leaks, does anyone know if these can be replaced?

Here's another brand sold by B&H:
http://www.bhphotovideo.com/c/product/71032-REG/Kalt_NP11117_Lid_with_Cap_for.html
I don't know if this is really the same as the Samigon posted earlier.
The price is $2 higher, so it must be better.

Mark Overton