Suggestion for drying cabinet heater

[cyrus]

I'm going with a single metal gym locker as a drying cabinet, it is cheap and available and does a good enough job -- personaly I don't use drying cabinets but aagain, it is cheap and available and what the heck, one more barrier for dust is OK by me. I was trying to figure out how to get air movement, though not strictly necessary, for the rare occasions that I need to rush drying along. Tradition says use a lightbulb but Im not too happy about light bulbs and damp, never mind trying to lightproof it... So, how about a coffee cup warmer? I think they're 25 watts, which should be plenty to get air movement , and I think they'd be safer around water spills, right?

[Tin Can]

Nix on a coffer heater. It's meant to be immersed and used for short times. I just played with one I found and I considered it unsafe at any speed. No ground wire for starters. I tossed it.

Heat rises. Let's think on this. A good idea will appear.



I'm going with a single metal gym locker as a drying cabinet, it is cheap and available and does a good enough job -- personaly I don't use drying cabinets but aagain, it is cheap and available and what the heck, one more barrier for dust is OK by me. I was trying to figure out how to get air movement, though not strictly necessary, for the rare occasions that I need to rush drying along. Tradition says use a lightbulb but Im not too happy about light bulbs and damp, never mind trying to lightproof it... So, how about a coffee cup warmer? I think they're 25 watts, which should be plenty to get air movement , and I think they'd be safter around water spills, right?

[cyrus]

Sorry, I meant the non-immersible type of coffee mug heater http://www.amazon.com/Mr-Coffee-MWBLK-Mug-Warmer/dp/B000CO89T8/ref=pd_bxgy_k_img_y That one is 17 watts.

[Tin Can]

$10, may as well let us know how it works!



Sorry, I meant the non-immersible type of coffee mug heater http://www.amazon.com/Mr-Coffee-MWBLK-Mug-Warmer/dp/B000CO89T8/ref=pd_bxgy_k_img_y

[cyrus]

If I dont get electrocuted first, sure.

[Bill Burk]

I don't think you need heat. Just time.

If you don't have time, well then yes you need heat.

See the clothespins in the upper right corner of this darkroom... I hang my film to dry there and just leave it a day or two.

I can't say for sure that I get no dust, but I have a hunch it all drains off.

http://beefalobill.com/images/darkroom1.jpg

[genotypewriter]

I'm reluctant to think that heat is a good idea unless there's a way for the hot vapors to exit. You don't want your lenses to turn in to dim sims :)

How about using desiccant and a very low power fan? Higher power fans will speed things up but also run the risk of sending dust inside the lenses, depending on the sorts of lenses you have.

[AtlantaTerry]

Actually, a light bulb is not such a bad idea. All you have to do is protect it from getting wet. One way would be to put a glass jar over the light and socket. Protecting the source from water would be true of almost anything that gets warm.

Are there not long strips of ... something ... that get warm? My dim memory seems to recall something along that line. If I am right you could install them on the vertical walls of the cabinet then cover them to protect them from moisture.

›

Back in the '60s when I was a photojournalist at a daily newspaper, we dried rolls of 35mm film in about 2 minutes with what was basically a metal tube with a heater/blower at the top forcing hot air down.

We would stick the stainless steel reels of processed film up into the tube then turn on the heated blower. When I got to the newspaper, that's just how it was done. But I did not like fighting with the dried film that was fixed into a tight coil because it had dried on the film processing reel.

So what I figured out was that I could halfway dry the 35mm film, remove it from the stainless steel reel then load it back onto the reel but with the emulsion facing out then finish drying it. Once I worked on the drying times I could get a perfectly flat dried roll of film. Trying to make prints or contact sheets with flat film rather than coiled film was a huge time saver that more than made up for the extra minute that it took to reload the reel backward.

[Andrew®]

Lightbulb works well in a confined space such as a locker, especially in winter.

[alexn]

Go to any pet store that stocks reptile care goods.. You can buy heater mats that are designed to go under the sand in a reptile enclosure, they use next to no power, get to about 80~90° F and the entire heating element is laminated to protect it against reptile bodily fluids... They are safe as anything, cheap, readily available and would definitely create enough warmth to get thermal convection happening..

[Cor]

If you have the time I would advice to "have as little air movement as possible to avoid movement of dust particles. I have a Jobo Mistral dryer with a dust filter on the inlet. But I never use it to dry film, I do run the dryer on hot before hanging my film, the idea being that the blower pushes out dust particles (not sure if that is really true) and to have a warm air in the dryer. I switch it off and let my films dry over night.

best,

Cor

[Jac@stafford.net]

The page below generously describes the design, tests and results of developing their drying cabinet.

http://www.rosyproducts.com/film_dryer.htm

[cyrus]

Oh yes I'm familiar with Rosy products, I got my sink from them. Their drying cabinet is indeed quite nice -- too nice, with adjustable timed heating etc,

I personally don't even use cabinet, and would rarely even want heat at all but kept this locker and repurposed it for the dust prevention. In the rare circumstance that I want heat I was considering options. A lght bulb even if protected from the damp, still generates light and so the cabinet would have to be lightproofed. I did look at the animal or seed warmers, but they're more expensive than the mug warmer. And, I have this mug warmer here ...

[cyrus]

I'm reluctant to think that heat is a good idea unless there's a way for the hot vapors to exit. You don't want your lenses to turn in to dim sims :)

How about using desiccant and a very low power fan? Higher power fans will speed things up but also run the risk of sending dust inside the lenses, depending on the sorts of lenses you have.

There are no real hot vapors created; the mug/bulb just barely puts out enough heat to create a very gentle current of rising air, so gentle that it doesn't stir dust. These lockers have air slits in them (which I cover with filter) and also have gaps

[jamesaz]

I built my film dryer with 2x2's as frame and some subflooring material, 1/8", for the sides, top & bottom, hinged door made of canvas & 1&1/2x 1/8 hobby wood. Drilled a hole in the side, stuck PVC 1&1/2elbow & a hair dryer from goodwill connected to a timer. Put some filter material in the outlet of PVC. Even painted it was a 2 hour project. Locks with a hook & eye that had to be bent but will hold 6 35mm rolls & 8 sheets (more if left in hangers) 4x5. Has a footprint about the same as a gym locker but no louvers whee dust could enter. Whatever you do, weekly take a clean damp rag and wipe down the inside. Good luck.

[neil poulsen]

I think that another name for these could be dust cabinet. The main thing is to keep dust off the negatives while they dry. Unless one's in a hurry, is heat really needed?

I made my "dust cabinet" from poplar that I purchased at Home Depot. It's the perfect size and can handle 4x5, medium format, and 35mm film all at the same time. I hang the strip film on the right, and I have shelves on the left from which I can suspend 4x5 sheet film. Works great.

[John Olsen]

Tom Fuller wrote a nice article showing how to make a dryer using a transparent garment bag. Total cost to me was $30 and I never have dust problems anymore. Drying time is about 2 hours with a 75W bulb at the bottom. I think it was in Shutterbug magazine in 2002. Ugly photo attached.
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[jeroldharter]

I would avoid heat, but obviously you are asking about heat. So you need something electric that produces no light. A light bulb is out. You could try a safelight bulb but those are low wattage and don't produce much heat. The pig blanket or heated floor mat would work but those are fairly expensive and inelegant to stuff in the bottom of a locker.

My Arkay drying cabinet had a heating element with a fan and filtered air intake. Never a problem with dust and I never used heat. So perhaps filtered air circulation would help you safely hasten drying. Maybe a computer fan with filtered intake?

[DougD]

Light bulb. My dad used a couple of 75W bulbs to keep dew from forming inside his boat.

[vinny]

Mine has a porcelain socket on the bottom with a 150w bulb in it. Directly above it is a piece of aluminum foil. The foil protects the bulb and catches any drips which evaporate quickly. Film is hung from binder clips and dries in about an hour.

[tgtaylor]

Like John Olsen above, I use a ladies garment bag (about $6 at Walmart) for air drying 120, 4x5 and 8x10 negatives. Takes about 4 hours in my closet and I have never had a problem with dust as the bag zips closed to prevent dust from settling on the film. Unless I cut the roll in half, which I never do, 135 is too long for the garment bag so I hang it from the grill of the ceiling heater in the bathroom and then close the door. Never had a dust problem even though I squeeze by to use the bathroom. Takes about 4 hours to dry and I can hang 5 rolls from the grill. I can speed up drying by placing a fan in the closet to circulate air out and into the bedroom or by placing the sheets in my Arkay CD-10 film dryer. But I seldom need to do that and usually use the dryer for overflows that the wardrobe can't handle.

Thomas

[jbenedict]

The commercial drying cabinets have a heater/blower at the top and a plastic zippered bag to enclose the film. The bag has holes on the bottom to vent the air, The blower onto has a filter on its input.

A gym locker usually has vents at the top and on the bottom. I would (and have seen) use one or two hair dryers for heat and air. The dryers usually have a 'cool' setting with no heat and a 'hot' setting with heat. If you are worried about dust, put something over the input vents to catch the dust- t-shirt material, paper face mask material. I have dried ten 36 ex. rolls of 35mm in ten minutes with no overheating.

[Kirk Gittings]

just use a "hard service" incandescent bulb in one of those old style ceramic bases with a 2 prong extension. That bulb will not shatter if water gets on it. Works like a charm. Get it all at Home Depot or equivalent for just a few bucks.

[Jmarmck]

There powered warps for pipes in colder climates. Not familiar with them but the idea might be useful.