I have tendency to look at simple things and mistakenly think, "Oh that would be easy to make!" and then get really pi**** off when it resembles a Homer Simpson BBQ, but....
I have a Nova 5 slot and it looks like sheets of acrylic bonded together, which could be simple to copy...
Acrylic is not that expensive, glue/resin or whatever adhesive is required is unlikely to break the bank, so have I failed to notice the diamond impregnated dividers that justify the £540 cost of a 20x24 12 slot? The inlet looks like a very simple garden/ plumming fitting, the outlet is a tube....
Anyone got any tips? I know of people making fish tanks with silica gel and glass that can withstand enormous pressure, so would this be any different in principle (using plastic of course). Presumably the correct plastic and suiatable adhesive is key.
As usual, I would be able to look my wife in the eye a little easier if I were able to make it for a snippet of the retail cost (sound familiar?). She was really please with my mongrel easel, negating the need for a new 20x24!
I made my own washer 20-years ago from acrylic - I copied as well as I could the Zone VI washers. It worked for about 15 years and then began to leak.
I've now bought a 10-gallon aquarium, cut a couple of pieces of PVC pipe the narrow width of the tank, and cut slots in the pipe for dividers. I put the pipe in the bottom of the tank then slip the dividers into slots. I use a siphon to fill and drain the tank. 8x10 is my largest size, so this arrangement works well for me.
With the development of akaline fixers, I don't believe there is the need for the extended washing that there once was.
I also built a 16X20 print washer along the lines of the Zone VI washer about 15 years ago. I still use it today along with a Zone VI that I bought used about 2 years ago. I used 1/4 inch acrylic for the walls on the one that I built. The Zone VI that I bought has 1/2 inch walls. Much more substantial. I wouldn't hesitate to build one again. Acrylic can be cut with a table saw. The necessary holes can be drilled. The gluing is straightforward.
I could go on at length about this subject as I have looked into building both an aquarium and a print washer from acrylic and have even done some small projects that didn't look like his BBQ but easily could have. I finally decided to buy a used aquarium and a used print washer because it was actually cheaper and would look better.
Acrylic is not cheap especially when you figure out the quanities and grades needed. All plastic is not equal despite looking the same and working it requires some precision and holding jigs in order to use the proper acrylic glues. It is do-able but will cost about half of retail and can easily rival Homer's work.
But if you decide to go for it I can dig out some sites for you to look into.
Fine Art Photo Supply sell kits for this if you are interested.
Mine is laughably simple and portable. And everything is done in the tub of our spare bathroom.
First, a tallish 1-gallon Rubbermaid cereal keeper or open tray containing HCA.
Then I use a 5-gallon plastic mop bucket, somewhat rectangular in shape. I hang a recirculating aquarium pump off the side. It moves the water around but is not intended to filter it. Badda-bing, that's it.
I give the prints 10-30 minutes before dumping and refilling the water. Two or three cycles and it's done.
Recently I've added another bucket and pump to make the process a bit more efficient.
The recirculating water keeps prints from sticking together. I'm comfortable with up to three 8x10s, several smaller prints or one 11x14 (gently curled up) at a time.
Anything larger, heavier or even slightly awkward to lift and move frequently is out of the question for me. I use the tub in the spare bathroom for fiber print washing sessions so I must be able to easily lift any archival washer for every session. That rules out all of the alternative homebrewed washers such as glass aquariums, etc.
Right now I'm torture testing a fiber print run through this setup. It's been taped directly to a sun-facing window for three months now. I plan to leave it throughout the winter since condensation is likely to occur some days. If it survives I'll declare my homebrewed archival mop bucket method officially safe and sound.
I made the same type of washer as Juan. Aquarium with plexi dividers held up with PVC pipe. I drilled holes in the pvc pipe for each compartment asnd stuck a tube into the pipe. I siphon from the center of the pipe. This lets me drain each area more or less evenly. I have tested for residual fixer and have found good results after soaking for 15 minutes, then draining 1/2 the auarium and refilling. Following another 30 minute soak they are clean. There is no reason to slowly run water with this setup, so I just fill with a hose. I can wash 6 11x14 prints with this setup and I think it cost about $50 and 1 hour to make.