Darkroom sink plans

[welly]

Hi chaps,

Currently in the process of putting together a darkroom with a couple of mates (jars on this forum and one other). We've got some ideas in our heads for how to build a sink but would appreciate any tips, advice or plans for a sink.

That's all!

Thank you,

Welly

[bob carnie]

Wood - using West Systems as the final coat to water proof.

Do not make it too high or you will always staining your shirts.
Make it bigger than you think you need.
Also a T design is fantastic , took me 30 years to figure this one out.
Figure a way to feed two separate water lines into the sink

I use heavy duty garden hose , commercial grade to the mixing valve which is basically a shower control with thermostate, way better than running copper behind the
sink and to areas of the sink.

Make sure you vent the drain and oversize the drain, with grill over top to stop larger items from going into the drain.
If you can put the sink on wheels if you have space... and quick connectors for the drain if you want to move the sink around... No kidding if you have space there
are many reasons to have a portable sink.


bob

[jk0592]

Wood - using West Systems as the final coat to water proof. This is what I used 25 years ago. It does resist water very well, but the Kodak Indicator stop baths stains the nice epoxy finish. Use it with care to preserve the sink, unless resanding and refinishing periodically. Recently switched to Ilford Ilfostop citric acid based, but did not spill any off tray yet...

[vinny]

What bob said. I coated all the edges of mine (west systems epoxy) before assembly as well. Mine has a wash basin buit in that drops down about 16", it make a good cleanup area. Use $40/sheet birch, not ac plywood. Make sure your assembled sink fits through the door and/or make the base it sits on as a separate unit. Mine was a bitch to get thru the door.

[Jim Noel]

I second the use of West Systems epoxy over plywood. I built one this way in 1989. I sanded and re-coated it last week.

Jim

[Peter Langham]

Depends on how big a space you have. Make it as big as you possibly can. Plywood with epoxy is the way to go. I used epoxy paint on top of epoxy resin. Utilize all the space underneath for storage or print drying racks. If the T shape doesn't work for your space consider an L shape.

[vinny]

here's the pics of the beast I built. I made it big enough to handle 20x24 trays (depth-wise).
860988609986100

[Ari]

I made one sink previously, and I went the PVC route.
A local store will cut all the pieces to the desired dimensions, add some corners and you're done.
You need to buy PVC glue and some Plumber's caulking to seal the joints.
But it can be assembled and built in an hour once you have all the cut pieces.

Mine was 7 feet long by 20 inches wide, and like many other sinks you'll see, the back was higher than the front.

[Michael Rosenberg]

I second the recommendation for PVC. I posted directions and pictures some years back on the LF Home page http://www.largeformatphotography.info/sink-manufacturing.html

It has now been 11 years that I have used this sink and no leaks. Very durable. No regrets - I had two other sinks over the past 25 years, both were fiberglass and what a pain. And they eventually leaked. An hour after I finished I was using the sink.

Mike

[ROL]

A Darkroom Portrait –> Process Sink (http://www.rangeoflightphotography.com/pages/a-darkroom-portrait#wetside)

[Chuck P.]

I used this (http://www.paintdocs.com/webmsds/webPDF.jsp?SITEID=STORECAT&doctype=PDS&lang=E&prodno=B70W211) to coat my sink, it has done wonderfully, but nothing wrong with the west systems for sure......

[welly]

Amazing response, thanks all!

[Ian David]

Interesting...
Those of you who are recommending West Systems epoxy on plywood: I gather that for this application it would be sufficient to just use the 105 resin + hardener as the final surface (i.e. no need to finish with varnish or polyurethane paint or similar)?

Many thanks
Ian

[vinny]

Interesting...
Those of you who are recommending West Systems epoxy on plywood: I gather that for this application it would be sufficient to just use the 105 resin + hardener as the final surface (i.e. no need to finish with varnish or polyurethane paint or similar)?

Many thanks
Ian
No paint, epoxy does need to be coated for outdoor use though. You can use powdered tints if you desire a color.

[bob carnie]

What vinny said

I never painted over the West, this stuff is great , I have taken apart and put back together my sink a few times, another layer of West and I am good to go.

someone mentioned getting the sink in doors , I agree put the sink unit on a platform that can be broken down if required.

No paint, epoxy does need to be coated for outdoor use though. You can use powdered tints if you desire a color.

[Ian David]

Thanks vinny, bob
I have a nice big plywood sink that I built 2 years ago. I was just starting to investigate possible coatings when new baby arrived and darkroom construction went off the rails. The West stuff looks to be readily available around here, and I now have a bit more breathing space. From a coverage guide I saw, it looks like 1L of 105 resin should almost do the job, so the cost is pretty reasonable too.

Cheers
Ian

[Martin Courtenay-Blake]

Whilst I don't have one myself I have seen large sinks in a number of darkrooms constructed from ply with a couple of layers of fibreglass and epoxy. As long as the wooden construction is appropriately braced and supported it should last for a very long time. If you don't use a gel coat or filler/colour in the epoxy the fibreglass goes almost completely transparent which is nice if you want the wood detail to show through.

[vinny]

Whilst I don't have one myself I have seen large sinks in a number of darkrooms constructed from ply with a couple of layers of fibreglass and epoxy. As long as the wooden construction is appropriately braced and supported it should last for a very long time. If you don't use a gel coat or filler/colour in the epoxy the fibreglass goes almost completely transparent which is nice if you want the wood detail to show through.

yeah, that's messier (unless you're experienced w/it) to do and the fiberglass is not necessary if the proper plywood and methods of construction are used. Now boats on the other hand.......

[Ian David]

When I was looking at coatings last time, I asked a boatbuilder down at the local chandlery. He was pretty convinced that I should be using fibreglass as well as the epoxy and building out the internal corners into beautiful smooth curves, etc. I am now glad that I didn't go down that road - more expensive, messier, and unnecessary according to the comments here. I think he thought I wanted a sink that would be holding lots of water, rather than just a water-resistant channel for holding trays and washing things off...

[Scott Walker]

When I was looking at coatings last time, I asked a boatbuilder down at the local chandlery. He was pretty convinced that I should be using fibreglass as well as the epoxy and building out the internal corners into beautiful smooth curves, etc. I am now glad that I didn't go down that road - more expensive, messier, and unnecessary according to the comments here. I think he thought I wanted a sink that would be holding lots of water, rather than just a water-resistant channel for holding trays and washing things off...

If your sink springs a big leak in the middle of a printing session it will suck a bit, however if your boat springs a big leak in the middle of the ocean it will suck alot. :)

[Bruce Pottorff]

I built my sink out of ply, and then took it to the local speed shop and had it sprayed with a high quality truck bed liner. Impervious to chems, never needs re-coating, looks sharp.

[bob carnie]

Ian .. your last line is very important to all here, West Systems will leak if there is enough water in a big sink. The pressure will force the water through all the edges.

So if you are planning to use this as a multipurpose sink... process prints,,, wash your clothes,,, take a bath,, then using fibreglass and going all out would be my vote.
Drainage and fast is important in any large sink, if the drains cannot keep up, (don't ask) then you can have leaks.





When I was looking at coatings last time, I asked a boatbuilder down at the local chandlery. He was pretty convinced that I should be using fibreglass as well as the epoxy and building out the internal corners into beautiful smooth curves, etc. I am now glad that I didn't go down that road - more expensive, messier, and unnecessary according to the comments here. I think he thought I wanted a sink that would be holding lots of water, rather than just a water-resistant channel for holding trays and washing things off...

[vinny]

If your sink springs a big leak in the middle of a printing session it will suck a bit, however if your boat springs a big leak in the middle of the ocean it will suck alot. :)

I actually installed a motor mount on mine in case this photography thing doesn't work out. I'll report back.

[jk0592]

When I built my plywood/West epoxy sink, i used a special fiber (or was it powder ?) compound also part of the West system, to be mixed with the epoxy, giving a heavy bead and a perfect seal for the edges. The bead can given the shape you want, so I made it into a convex shape by passing a wooden dowel over the bead.

[vinny]

When I built my plywood/West epoxy sink, i used a special fiber (or was it powder ?) compound also part of the West system, to be mixed with the epoxy, giving a heavy bead and a perfect seal for the edges. The bead can given the shape you want, so I made it into a convex shape by passing a wooden dowel over the bead.

Fillet, a fine sawdust of sorts.