Inexpensive Super 8 home processing tank made from PVC drain pipes
Developing Super-8 stock yourself is fun, brings mostly great results and saves a lot of money. Below is described how everyone can do this now. You only need a handful of standard parts from the nearest DIY, a few tools and some patience.
Follow up:
Results are as good as home processing gets — I assume most people doing this take some uniqueness of the results into early consideration anyway. :-)

I got the idea for this project over time and partly while actually working on it — I'm sure there is room for improvements and thus I would appreciate any feedback! :-)
Shoppinglist for the DIY
You need:
Tools
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Core Component
First we take the 3" tube to build the inner core of our processing tank. Trim it to 30.5" (77cm) - ask in the DIY if they can do this for you, thus you avoid saw dust and work. PVC is ductile. You now drill a minimum of 32 holes with your 3/8" (or bigger) wood drill into the pipe. The chemicals have to get well-stirred, so it's better to do a few extra. You now should deburr all holes carefully with the box cutter.


Now it is time to make the racks/spacers from the clothesline — this keeps the film strip
away from the pipe surface. To do this, drill 8 equally spaced holes in each end of the pipe. Through these you thread the clothesline: Start with a firm knot and "weave" through the pipe under constant tension. End with another knot, which should be as taut as possible.
To increase precision, you should now fix the clothesline with some 4" strips of hot-melt adhesive. Roughen it to avoid bumpy seams, and keep it away from the pipe ends — we need space here to mount the film end with a stapled loop later on. Watch out that the adhesive does not creep out, cut all adhesive threads away carefully.

Now you need to sacrifice a film — exposed or unexposed, you need a small reel with 15m (50 ft) film that might get scratches while mounting the guide wire. It is helpful to mount this reel on a viewer or projector thus the film unwinds easily and straight. Staple one film end to a loop around the clotheswire and push the loop to the very left edge.


Now you need to take your time and be sharp-eyed — take your glasses if necessary. Under tension rotate the core and wind the film from the left edge with its emulsion facing towards you around. The film has to be seated planar and solidly, and each winding has to have exactly 1 mm (~0.04") distance to the next. It is important to work accurately here -- better check the film distance every three turns with a little bell wire loop.
After a few windings, you will get a good feeling for "exactly 1 mm" and the procedure gets easier. Don't stop verifying though, take a ruler to check if 5 windings are exactly 44 mm (1.73") from most left to most right film edges. Fix the films position with a narrow strip of duct or masking tape. Once again, don't rush. If you are uncertain, make the core a little longer and leave a little space for tolerance. After about 64 windings the film should be spread over the pipe. Fix the end as the beginning, but through a rubber band loop to keep the film tensioned.
Now you wind the bell wire in-between. Drill a little hole next to the film's beginning and mount the bell wire with a tight luster terminal on the inside of the pipe. Again with heavy tension, unwind 15 m (50 ft)from the roll. It is important to unwind and not just pull from the ring to avoid radial windings of the wire! Fix the end with another tight luster terminal. The wire should be seated firmly and equally spaced on the clothesline, thus it stays were it is even if you touch the core in the dark.
You now can rewind the film on the wheel. Push the small slip-on sleeve on the thinner end of the pipe. Congratulations - the hardest part is done!

Outer core
Now to the casing, which will hold the core with the film. Trim the big (4.3") tube — it should become 2" longer than the inner core. Push the big slip-on sleeve (110mm = ~4.3") on the thinner end, so far that the drain pipe socket plug is well leakproof but still removable with some torque. You need to try that out carefully.


Drill a 1" hole into each drain pipe socket plug, if necessary, extend the whole carefully with cutter and round file. The hosepipe connectors should be right about screwable into these holes.
You now need to shorten one end of each hosepipe connector. They also need to be(come) light proof and should not expose any reservoirs for chemicals, so fill them up with hot-melt adhesive and make sure that chemicals can stream out fast and easily.


Using the cutter and one cap nut of the hosepipe connector as a jig, cut two 1" gaskets. The inner diameter should be just about 1". If you want, you can now also drill holes from the side through the hose connector, thus the chemicals can drain out easier. Unfortunately, I did not get the holes on the connector and the cap nut congruent — I think though I can afford losing a few drops of chemicals due to the remaining "footbath" :-)

Now mount the socket plugs with the gaskets, the hosepipe connectors and two 1.5 ft pieces of hosepipe. Tighten the screws really firmly &mdash you really want to avoid any light leaking in! For the connectors I used, the gasket was better placed on the (dry) outside. If in doubt, put gaskets on both sides.
If you have not done so yet, clean all parts now carefully. Important are the gaskets holding the socket plugs — mine were covered with silicone goo. I doubt the chemicals would appreciate that. Now put the inner core in the outer casing, push in the socket plugs — That's it!

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9 comments, 1 trackback
this is by far the most impressive do it yourself i've seen - just wondering if I attempt it, do you have a recipe for the processing chemicals? or any advice on quantities
Allyn
thank you, thank you.
Yes, there sometimes is anti-halation layer, which is annoying. A steel cylinder would have the disadvantage of pretty quickly getting solution's temperature down though.
Just an FYI, I was referred by homepage_mac_com_onsuper8_process_html and was given an error that they are a sp@mmer... I'm fairly sure they are not so your sp@m filter might be a tad too tight :)
LOL it won't even let me say the word!


