Chems and aluminum?

[Flotsam]

When trying to get my film developing solutions to temperature, I put them in a dishpan of water of the correct temp. The problem is that the plastic bottles and graduates that I have my stop, fix and wash aid in don't transmit heat very well so it takes quite a while for the solutions to stabilize at the proper temp. I would love to find some stainless steel beakers to measure my solutions into just prior to use but they are very expensive.

Now my question. I ran across some inexpensive spun aluminum cups in a discount store. If I just crimp a pouring lip into the edge they would be perfect and would transfer temperatures from the water bath in a flash. My worry is possible chemical reaction between the chems and the aluminum. I have an SS graduate for the Developer so I'm just concerned about the others, mainly the stop and fix..

Any thoughts or [cheap] alternatives?

 

[Jon Shiu]

Hi, if you put hot water in the dishpan, ie 110 deg. your developer will come up to temperature much faster. Have to watch it though and pull it out when it is within 1 or 2 degrees of 68 deg. because it will continue heating up when you take it out. If it gets too warm, I cool it down by immersing a small water bottle that I keep frozen in the freezer.

 

[Joe Lipka]

I am fond of styrofoam coolers and aquarium heaters to keep bottles or jugs of chemicals warm.

I have also used plastic sandwich bags filled either with ice cubes (to cool) or hot water (to warm) beakers of chemicals by immersing the plastic bags in the chemicals. Just need to make sure that you have separate marked bags for the various chemicals.

 

[gainer]

Not a good idea. Aluminum is quite reactive. You can also get thin plastic drinking cups of various sizes. You can squeeze a lip as you pour.

I have learned to use a microwave oven a few seconds at a time to raise the temperature of solutions in glass or plastic containers. This has the advantage that stirring, with its consequent aeration, is not necessary. You can't leave a metal thermometer in the solution, though.

 

[rogueish]

I have learned to use a microwave oven a few seconds at a time to raise the temperature of solutions in glass or plastic containers.

Be carefull of any liquid heated in microwaves. (this mostly applies to boiling liquids) Microwaves tend to heat liquids in layers, often causing a cooler layer under a hot layer, under another cooler layer. When the vessel is moved, or worse, tipped to take a drink, the layers mix and often "overboil" or seem to "explode out of the cup". Many people have suffered 3rd degree burns from this.
It's likely that this will not apply to gainer's method as the temps involved are lower, but it is good to know if you zap your luke warm drink.
Stir first, then move and drink.

 

[Art Vandalay]

I would've thought that due to the thinness of the container walls that there would be little difference between plastic and metal in this situation. Have you measured the transfer rate between the two container types?

Regardless, I wouldn't use the aluminum because it will definitely react with some of the chemicals - that's why 'stainless' steel is the only metal used in film processing.

 

[Melanie]

HI
I use a old igloo, around 2 gal, that i put warm or hot water depending on B/W or color film,around three to four in of water, then i put my dev, etc in there and put the lid on it, i don't tighten it just placed it on the top.
and I have a thermometer in each plastic bottle and take out each when there close to there temps. works great and the igloo keep its temps for a while. and only takes a few min to heat every thing up.
Melanie

 

[Alex Hawley]

Not a good idea. Aluminum is quite reactive.

I consider Gadget to be the chemistry authority here and he is quite right. Aluminum is highly reactive. You will most likely get some ugly results that are unmistakeably visible on your film and prints.

Stainless steel is OK for most chemicals we use, but don't use it for selenium toner. The selenium reacts with the iron in the steel. Again, unmistakeably ugly results.

 

[Flotsam]

Thanks everybody. I expected that the advice would be to stay away from the aluminum cups which is why I left them at the store until I asked about it here.

I would've thought that due to the thinness of the container walls that there would be little difference between plastic and metal in this situation. Have you measured the transfer rate between the two container types?

Not formally, but from observation my metal graduate definitely conducts the water bath temperature quicker than my Jobo bottles and graduates.

I use a old igloo, that i put warm or hot water depending on B/W or color film

I think that is important to specify that you are referring to an Igloo brand cooler. I'd hate to see a careless post result in an epidemic of homelessness among Eskimos

 

[Helen B]

Damn! I've just bought a job lot of 129 old igloos on eBay, buyer collects.