Tray Warmer?

NortheastPhotographic · Jan 13, 2020

I'm having a heck of a time maintaining the temp I'd like my tray of Ansco 130 to be. I try to keep my space at about 68 but as you get farther from the heater any liquids cool down. I think my tray would revert to about 63F after a short while. I've attempted to use water baths but these are a bit inconsistent and need semi constant minding. I see that Kaiser makes a product that would be perfect but it seems a bit over priced IMO (https://www.macodirect.de/en/darkroom/paper-developing/developing-trays/5529/kaiser-tray-warmer).

Any ideas? I typically use 8x10 or 11x14 print trays, never any larger.

John Galt · Jan 13, 2020

you can buy electric heating mats meant for growing seedling plants . . . I have used them to start seedlings in my basement (with grow lights) for spring planting in the garden. There are also thermostat controls to maintain temp . . . check it out at your local garden supply store . . should work for you want but don't expect + or - 1 degree control

https://www.burpee.com/gardening-supplies/heat-mats/seedlings-heat-mat-prod001232.html

summicron1 · Jan 13, 2020

you can buy food warming trays -- try the thrift stores in your neighborhood.

NortheastPhotographic · Jan 13, 2020

John Galt said:
you can buy electric heating mats meant for growing seedling plants . . . I have used them to start seedlings in my basement (with grow lights) for spring planting in the garden. There are also thermostat controls to maintain temp . . . check it out at your local garden supply store . . should work for you want but don't expect + or - 1 degree control

https://www.burpee.com/gardening-supplies/heat-mats/seedlings-heat-mat-prod001232.html

Are they low temp running? Ie anywhere in the range of 70-75F?

Steve Goldstein · Jan 14, 2020

My FarmTek catalog arrived in the mail just yesterday. They offer several different heating mats for seedlings. Most of them need to be used with a thermostatic controller, which FarmTek also sells.

For years I've used a similar mat from Kane Manufacturing . It also needs a thermostat, and I fulfill that role. The mat is powered by a small variac. Over time I found the right setting so that the tray temperature, as measured by a small immersed thermometer, moves very slowly. If the temperature goes above 72F I turn off the variac and let the developer temp slowly drift down.

M Carter · Jan 14, 2020

Check ebay for "salton warmer". They have temp control knobs and tempered glass tops, I use them for lith printing. I have two hooked to a single dimmer for large trays. they come in all sorts of sizes.

David Brown · Jan 14, 2020

This issue has come up from time to time. Surprised that no one has (yet) mentioned "pig warmers" ...

fiddle · Jan 14, 2020

I tried the plant warming mats. Was not enough. Only raised the temp 2 degrees at most. Read about the pig warming mats, but they are fairly expensive for a test. My basement gets pretty cold, II just need to wait for warmer months to print.

Steve Goldstein · Jan 14, 2020

The Kane mat I use is sold as a pig warmer. Or maybe a piglet warmer.

Fortunately in this case (though not in general) my darkroom is quite small. In winter I run a 1500W oil-filled electric heater; I usually only need to use it at half power. The space gets warm enough that tray temperature drift is manageably slow when I turn off the variac. In winter my darkroom is the warmest place in my deliberately cold house!

mshchem · Jan 14, 2020

NortheastPhotographic said:
Are they low temp running? Ie anywhere in the range of 70-75F?

My Dad was a fanatic gardener, he used the bed heaters. A big tray with sand with the heater.
Another possibility is to try a dimmer, and a heat tape?? Out here in farm country there's all manner of water bucket heaters for livestock, not sure how they work. A low power heating element and a simple time on time off control ??.
I would also consider a small electric baseboard heater and a thermostat in your darkroom to act as a helper. I run a small oil filled electric radiator on lowest setting, only pulls 700W and that's on and off keeps a otherwise chilly basement darkroom at 68 to 72 F.

Don't burn down your lab

foc · Jan 14, 2020

You could try a homebrew heating tray or mat for your trays.
It is always best to have the ambient room temp slightly higher than your tray temps.
When I heated my darkroom, many, many years ago, I would turn on the room heater one hour before I would start my darkroom work, giving the room and the contents time to warm up.
BTW my darkroom was a converted concrete coal shed, so it was a fridge in winter and an oven in summer.

NortheastPhotographic · Jan 14, 2020

I did just acquire a Nova 12x16 slot processor that would do just fine. I was just planning on leaving it filled with RA4 chemicals and doing normal tray work for B&W. Hopefully I can still find a solution that works for me. The seed warmer plus thermostatic controller look like the best bet.

removed account4 · Jan 14, 2020

David Brown said:
This issue has come up from time to time. Surprised that no one has (yet) mentioned "pig warmers" ...

YES!
i think the good folks at ULINE sell a waterproof electric livestock warming blanket ( pig warmers ) .
from what i remember that was the traywarmer-thingamabob of choice people used
if they didn't have a "water jacket" type thing going on.
good luck and enjoy the 130 ! love that stuff
john

MattKing · Jan 14, 2020

David Brown said:
This issue has come up from time to time. Surprised that no one has (yet) mentioned "pig warmers" ...

One of my all time favourite APUG threads (the link is no longer valid though): https://www.photrio.com/forum/threads/sue-weeee.25459/

RalphLambrecht · Jan 14, 2020

NortheastPhotographic said:
I'm having a heck of a time maintaining the temp I'd like my tray of Ansco 130 to be. I try to keep my space at about 68 but as you get farther from the heater any liquids cool down. I think my tray would revert to about 63F after a short while. I've attempted to use water baths but these are a bit inconsistent and need semi-constant minding. I see that Kaiser makes a product that would be perfect but it seems a bit over priced IMO (https://www.macodirect.de/en/darkroom/paper-developing/developing-trays/5529/kaiser-tray-warmer).

Any ideas? I typically use 8x10 or 11x14 print trays, never any larger.

definitely overpriced!

markbau · Jan 14, 2020

foc said:
You could try a homebrew heating tray or mat for your trays.
It is always best to have the ambient room temp slightly higher than your tray temps.
When I heated my darkroom, many, many years ago, I would turn on the room heater one hour before I would start my darkroom work, giving the room and the contents time to warm up.
BTW my darkroom was a converted concrete coal shed, so it was a fridge in winter and an oven in summer.

+1
I use a home brew mat with the probe directly in the developer, temp stays within half a degree. I usually use stainless steel trays.

mshchem · Jan 14, 2020

https://kanemfg.com/products/livestock/hogs/heat-mats-thermostats/

Oink

Bill Burk · Jan 14, 2020

I pour about a gallon of hot (about 125 degrees F) water down the sink under the trays. If one doesn’t bring it up to 68 I pour another.

Ben 4 · Jan 15, 2020

I've had success with a water bath and aquarium heater for the developer. I place the developer tray in a larger tray partially filled with water; the aquarium heater (set to about 70) goes in the water bath. A little kludgy, but works fine.

bernard_L · Jan 15, 2020

foc said:
You could try a homebrew heating tray or mat for your trays.

Respect electrical safety standards!

bernard_L · Jan 15, 2020

Steve Goldstein said:
The Kane mat I use is sold as a pig warmer. Or maybe a piglet warmer.

Pet warming mat here (accommodates only one piglet, I guess). Thermal contact with dev solution is not good, so I set the mat's thermostat at 30°C, and the (paper) developer is at 22°C in a room at 17°C.
I made sure to choose one running from a low voltage: the mains AC stops at the AC/DC supply plugged into the wall outlet.
https://www.amazon.fr/dp/B07H86Z8S6/ref=pe_3044141_189395771_TE_dp_1

markbau · Jan 15, 2020

bernard_L said:
Respect electrical safety standards!

There is absolutely nothing unsafe about using a homebrew heating pad (or a water bed heater) to warm a developer tray because every darkroom circuit should have a GFI. Obviously you wouldn't immerse the pad in water.

bernard_L · Jan 15, 2020

markbau said:
There is absolutely nothing unsafe about using a homebrew heating pad (or a water bed heater) to warm a developer tray because every darkroom circuit should have a GFI. Obviously you wouldn't immerse the pad in water.

Probably we have a couple of misunderstandings here.

I did not mean that using a homebrew heating pad is per se unsafe, only that if you do, you better be aware of safety issues, with electricity and water in close proximity. If you know the how and the why of electrical safety, fine.
When I read "homebrew" I thought "totally homebrew", while actually you are using a commercial-off-the-shelf item. Although I would not blindly trust the electrical safety of such bottom-price articles.

every darkroom circuit should have a GFI

"should", yes; I've already seen strange things done by professionals, like:

running electrical wires through a metallic frame, and then insert self-tapping screws into that frame; (how did I find out?)
installing a 3-wire mains receptacle, with no ground connection

Nice prints to you.

Tray Warmer?

Moderator

Privacy & Transparency

Privacy & Transparency