Temperature Controlled Cabinet for Chemicals

[Eric Woodbury]

I thought there was a thread on this, but can't find.

In these winter months, it takes me so long to get all the chems up to temp to develop film. I have to get my hot water heater warmed up and the darkroom heater going. Then I have to get all the chems to 68F. Takes too long. Does anybody use a cabinet with their developer/water/fix in it, that you can turn on the day before and have everything ready? Do you find that it is handy? I have a little space still in my darkroom. I could probably build something to hold a couple of gallons.

Your thoughts please.
Thanks, EW

[jp]

I mix hot+cold water together to quickly get it to 68f. My fixer jug warms up from about 55f to 68 in a tray of hot water during the prewash/develop/rinse-stop steps prior to fixing. I have hot water always, so that works for me.

One option would be an instant on hot water. available in electric or propane. Makes water hot as soon as it flows through it via a little heater under the sink or on the wall. Not a huge volume, but adequate for your use.

Surely over kill and not needed by me but along the lines of what you're asking is the "powerblanket" product. It is a low power insulated+heater+thermostat warming blanket (and other shapes). I have one for thawing ground in case I have to rob a grave in the winter time. (It's actually in case I need to redo a guyed tower footing in the winter and must keep the concrete from freezing.)

[jeroldharter]

Try to find a used Phototherm water bath or else a Jobo TBE-12. They are good low temp water baths for tempering chemicals. A DIY alternative is to use an aquarium heater in a plastic tub.

[Steve Goldstein]

I had this same problem here in the northeastern US. My chems are stored on a shelf in the basement, in the same room with the oil furnace, that I've found stays very close to 68F all year. I set my trays on a 44"x18" Kane heating mat run off a small variac set at about 55V. This will very slowly raise the temperature up to 72F over about 1.5 hours, at which point I turn it on and off every 15 min or so to maintain around 70F. An in-tray thermometer and a look-up table taped to the wall tell me how much developing time I need for the indicated temperature. This particular Kane mat will hold 4 10x12 trays (I like them for 8x10 processing) or 3 11x14 trays, with the second fixer tray not temperature-stabilized. A 1500W portable oil-filled heater manages the darkroom, but I only need to use the 750W setting because the space is quite small.

For film I fire up both heaters ahead of time, 30 minutes is more than enough, and just work on the surface - the developer temperature doesn't change enough to matter over the developing time. I also use a lookup table to adjust film developing times based on the developer temperature just before the lights go out.

My darkroom is a small bathroom with only a toe-kick heater, but since I disabled the heater's fan to reduce dust the house heating system doesn't do much for the space. That zone of the house is at 58F-64F depending on the hour, yet I always have a reasonably comfortable working space and sensible developing times. The only real drawbacks are the needs to plan ahead (turn on the heaters) and to schlep bottles of chems from and to the basement.

[N Dhananjay]

I use these heating mats you can get from plant growing suppliers to line the bottom of my sink and rest the trays on them. DJ

[ic-racer]

I use liquid concentrate of all solutions and mix them with tempered water and I am ready to go quickly.

[MrFujicaman]

Eric-

My copy of Petersen's Photographic "Photo Equipment You Can Make" has plans for a solution warming cabinet. PM me your snail mail address and I'll send you copies of the plans.

[Stoogley]

I use a 19qt Rubbermaid storage container with a 125w submersible aquarium heater. Works great. Total cost: ~$30.00

[BradS]

I use a 19qt Rubbermaid storage container with a 125w submersible aquarium heater. Works great. Total cost: ~$30.00

Brilliant! Thanks.