Sinks and misc.

[dmr1]

In process of building out darkroom. Its a garage conversion . Or at least part of it.

As for sink height I assume something about elbow high??? Any coment on this. When I say elbow high I mean the top edge of sink. I assume the botom to be about 7 inches or sow below htis point.

I currently have installed a laundry sink against a common wall with house . unfortunately the new long sink will be on perpendicular wall with no plumbing ( drainage) . I intend to run pvc pipe as a drain to the laudry tub and let it drain into the tub. Are ther any isues with this as far as drainage goes.
There will be about a 6 foot run with severl 90s involved. Will this work without a vent stack. ???

Lastly do any of you use an air purifier in you drkrom and do you find that this helps witrh dust control. ?

Thanks for all replies.

Ken

 

[firecracker]

As for sink height I assume something about elbow high??? Any coment on this. When I say elbow high I mean the top edge of sink. I assume the botom to be about 7 inches or sow below htis point.

My sink is about 8 inchs deep, and its top is set a bit lower than my elbows,which is where I feel most comfortable using it. I tested a few times before making the legs with 2x4".

 

[resummerfield]

You should be able to drain your darkroom sink over to the waste pipe below the laundry sink, but be sure to allow at least ¼-inch drop for every foot of run (in your case, at least 1.5 inches drop, but more than that would be even better), and use at least 2-inch pipe. You don’t need a vent stack, but I would install a small “cheater” vent (a self-contained one-way dry valve sold at most plumbing stores) near your darkroom sink trap, to prevent that trap from being pull dry when the laundry sink drains.

Ventilation is important, so install an exhaust fan near the sink, and filter the intake or make-up air to help with the dust. There are several very good threads about darkroom ventilation on APUG.

 

[aznative]

I stood by my sink with my arms hanging at my side and it's pretty close to elbow height. I then measured from floor to top rail and it's about 41" with the sink bottom about 35" from the floor. I prefer to stand at my sink but some prefer to use a stool for sitting and so their needs may differ. You can check out pics of my darkroom in the "Darkroom Portraits" thread. There are a lot of good darkrooms represented there. Have fun building your darkroom.

 

[jp80874]

Variations seem to work well. My eight foot by thirty inch stainless sink (second hand Arkay - $300) is seven inches deep. The upper lip is four inches below my elbows. I cut the legs so the fluids flow towards the drain hole. This means that trays need a slight prop under one end to keep them level. Not having any plumbing background I did not think of a J trap or a vent. The drain is 1.5 inch PVC and runs through several 90 and 45 degree bends, 35 feet to the laundry sump. With all those mistakes you would expect some problems, but it has worked like a charm for nearly three years.

Beware of the most common mistake in exhaust fans placement. Many people put it right over the sink. This draws the fumes out of the trays, past your nose and eyes and out of the room. Bad choice. I have two fans sucking through four inch PVC pipes. The intakes are across the sink from me at sink top level, 2.5 feet in from each side of the sink. The filtered fan blowing air into the 11x13 foot room is behind me so fresh air blows from behind me across the trays and out the exhaust.

I am not fond of the grading sound that many bathroom fans make. Photography and darkroom work are my retirement joy. I don’t want to mess it up with grinding motors. Panasonic makes Whisper Fans in various capacities that are two to three times the price of bathroom fans, but all you hear is the “whish” of air in the pipes. Find them mail order by Google. My exhaust fans fit between the rafters and go outside. The intake is in the wall going through a high quality furnace filter.

When I play music it sounds like music. When I don’t play music all I hear is the thought process. Sometimes when I make mistakes that is grinding, but that is another story.

John Powers

 

[Monophoto]

Ken -

When I designed my sink, my frame of reference was the kitchen. If you are comfortable with the height of your kitchen sink, then that's about the right height for your darkroom sink. If the kitchen is uncomfortable, you can scale up or down as required.

I made my sink from wood - ordinary D-select pine with a plywood bottom. I used waterproof resorcinol glue and screws to put everything together, an oil-based primer, and then several coats of two-component epoxy paint. Sadly, after about 20 years of use, it needed to be repainted. That time I used a single-component water-based epoxy floor paint - and while that's ok, the finish is not as hard as the original two-component finish.

My sink has a flat bottom with a slope to the right. At the right end, I set a small stainless steel sink (the kind designed for travel-trailors) under the faucet. This serves as both the drain and also a deep sink for mixing chemicals. I'm still undecided about duckboards - there are times when I think they would be nice, but there are also times when I link the flat bottom.

My sink drains into a reservoir (actually a Rubbermaid bin) under the sink. It is directly below the shower in the master bathroom, and the drain line from the shower runs behind the insulated basement wall at an elevation that is well above the sink. So I have an ordinary Home Despot sump pump in the reservoir to pump the gray water up to the drain line. A float switch on the pump makes the system automatic.

Finally, I build a rack under the sink to hold print drying screens.

The one thing that I wish I had done but didn't - put a strip of half-round at the top front edge of the sink to act as a rubbing strip. Of course, I could always do that before I repaint it the next time.

John's point about the venitllation fan is very good. You really want the air flow to be away from you as you are standing at the sink. In my new darkroom, I chose to go with positive pressure ventillation - use a fan to force air into the darkroom through a filter, and then have it flow out through a vent above and behind the sink. I also strongly agree with his point about the noise - I chose to use a computer-style muffin fan that is mounted outside the darkroom. Air flows in through a plastic bathroom-style ventillation duct. The result is so silent that I cannot hear it - I chose to wire the darkroom with a master switch at the door that controls both the white and safe lights and also the fan, and then put a second white light switch next to the enlarger. That way, I can turn on the fan when I 'power up' the darkroom, and the fan goes off when I leave and "power down".

By the way - all of the receptacles on the wet side of the darkroom must be on a ground fault interruptor. Actually, it wouldn't hurt to have all of the darkroom receptacles on the GFI. Electrocution interferes with creativity.

 

[trhull]

Ventilation

Is my assumption correct that there is no way to ventilate without an external source of air, e.g., pipe, etc? I want to put a darkroom in my townhome that is being built, but I have no outside access.

 

[jp80874]

If it is being built ask the builder. Maybe they could add a duct in the rafters that could go somewhere you could dump smelly fumes. What a surprise for your new neighbor.

John Powers

 

[raucousimages]

I put in an Orec brand air filter, I now have very little problem with dust.

 

[Monophoto]

Ideally, ventillation involves exhausting stale air outdoors. Inlet air can come from within the house.

Practially, however, I've never had the ability to exhaust to the outside. Instead, I exhaust into the basement. Since the basement is 20X the size of the darkroom, and since it is tied into the rest of the house, the air coming into the darkroom fresh enough.

 

[Loose Gravel]

If you are draining into an open sink or tub, you don't have to have a vent or trap. The vent is to give stack gases a place to go and to keep your trap from siphoning dry. With no stack gases on the far end, there is no concern of this. If you hook into the sink below the its trap, you need the darkroom trap and, as mentioned, 'autovents' are the easiest.

 

[dmr1]

Thanks Eric. Actually the idea is to just run a drain pipe over to the laundry tub and let the large darkroom sink drain into the tub from the top withought tieing into the plumbing per se. Im just curious if its going to drain properly without a vent stack on the line.

 

[resummerfield]

So long as you have sufficient drop (1/4-inch per foot of run for a 2-inch pipe), your darkroom sink should drain fine. I thought you would cut into the laundry sink drain below that sink to get the necessary drop, as the traps on both sinks would probably be about the same height. But it you can discharge into the top of the laundry sink and get enough drop, it will work fine without a vent. Based on what I have been taught over the years, I would not go smaller than 2-inch pipe, however I see John Powers used 1.5-inch and had no problems. The smaller the pipe, the more drop you’ll need for a satisfactory flow.

 

[jp80874]

The drain and down spout from the Arkay sink I used was 1.5" OD. With that size at the start there would have been no point in going to a larger size pipe. My drop is 24" plus a slight grade built into the basement concrete floor. The 35' pipe goes right into the sump at the other end of the basement. With that drop the fluids come out as a torrent.

John Powers