Gray-B-Gon wind-powered evapotron for graywater disposal

Step 6 Materials

• matte or satin finish water-based exterior polyurethane varnish.
• paintbrush.
• masking tape, white or blue. (These instructions call it "blue tape" but you can use either.)
• about 50 mini zip ties.  Black stands up best to UV.
• ball of light polypropylene twine, 400 ft or so. Hardware stores carry it. Polypro is strong but not stretchy, and on the playa resists UV degradation better than some other materials.
• cutting oil, for drilling in metal. 3-in-1 or WD-40  is better than nothing.
• 30 medium (1-1/2" or 1-5/8") galvanized flathead drive screws.
• 13 small (1") galvanized flathead drive screws.

For the tray

• two 8-ft 2x4's, or enough material for two 45" lengths and two 29" lengths.
• 1/4" exterior-grade plywood, 32" x 48".
• six builder's shims, about 16" long.
• eight 3" galvanized flathead drive screws.
• 28 medium (1-1/2" or 1-5/8") screws.

For the masts

• 2x2, small tight knots ok, enough for a 5-ft and a 1-ft length.  I have used common pine successfully.
• 1/2" exterior-grade plywood, at least 11" x 25", for gussets and feet.
• one metal angle bracket, Simpson GA2, for the propeller.
• two metal angle brackets, Simpson A34, for drum wheels.
• four 1" screws for mounting A34's.
• twelve 1/4" carriage bolts 2-1/2" long, with washers and nuts.
• two 3/16" or 1/4" carriage bolts 1" long, and four nuts, for mounting the GA2 bracket on the propeller arm.  Your hardware store may have one of these bolt sizes, but not the other. A 3/16" thread may also be described as 10-24.
• Two medium screws, for mounting the propeller arm on the power mast.

For the drum

• 1-1/4" ID ("inside diameter") PVC pipe, 24" long.
• 1" ID PVC pipe, 3" long.
• (optional) one 1" screw.
• 80 ft. of light polypro twine (from ball, above).
• two bike wheels of the same size.
• tulle (polyester or nylon mesh), 2-1/2 yards, black or colored:  available at fabric stores. Cutting a full width (54" or so) lengthwise gives you two usable panels about 27" wide. Get the finest mesh available.
• mini zip ties (in Materials, above).

For the pulley wheel, propeller, and drive belt

• one bicycle rear wheel with either a threaded hub or a freehub.
• one extra axle nut, or one quick-release skewer and nut.
• aluminum sheet, enough for five 9"x12" or 8"x12" pieces depending on wheel size. Ask for 12" flashing at a hardware or building-supply store.
• thin cardboard for blade template.
• emery cloth.
• 30 mini zip ties (in Materials, above)
• 1-1/4" ID PVC pipe, 1" long (cut from the drum's 24" piece).
• 5-1/4" 3M "Safety Walk" gray anti-slip tape, 1" wide.  Hardware stores sell it by the foot.
• one CD, and one suitable plastic bottle or jar.
• four nylon stockings or sheer panty-hose legs. Ladders and holes are ok.
• 2-3 ft 12-gauge copper wire, bare or insulated, for propeller balancing.
• for freehub propeller wheel: 1 ft. bare 16-gauge copper wire.
• for threaded-hub propeller wheel: 1 ft. bare 20-gauge copper wire, and a bottle of Gorilla glue.

The  copper wire is available in hardware stores.  The 16- and 20-gauge copper wire is also available in craft stores.
Propeller mounting takes less time and effort if you have a hollow axle and a quick-release skewer and skewer nut.  Drilling the GA2 angle bracket in Step 12 will also be easier.

On the playa

• tools, including a cordless drill and bits, and an adjustable crescent wrench.
• nuts, bolts, and washers for connecting mast & gusset assemblies to the tray.
• 5-gallon plastic bucket.
• spare zip ties.
• one pair of panty-hose with no holes above the knees.
• light polypro twine (leftover ball from drum building).
• 4 mil black plastic sheeting,  42" x 54" .
• eight 1-1/2" square plywood staples, cut in Step 7.
• eight 1" screws (8 of the 13, above).
• bucket cushion: fabric (towel, clothing, burlap, etc.) scrap, 14" square or larger.
• fresh 3-qt jug of Clorox Regular Bleach or equivalent.  See Step 32 for info on chlorine bleach and how to apply it.

Comments

[extrordinary1]

Very nice job making your blades. Do you have a template I can get for this pattern? I see the holes you made for securing the vanes to the wheel, obviously with the zip ties you mention. I may wish to use a 26 inch wheel and secure 4 cogs to catch another set on another shaft, to crank a small low powered 12 volt generator to trickle charge my scooter battery when needed.

[Larry Breed]

The image in step 22 will help. Hand-sketch a shape you like, and cut it out. Variations in blade shape don't seem to affect performance much. The locations of the holes depend on the wheel's spoking -- you don't drill holes until you're confident you've found a good blade position. Steps 23 and 24 describe the constraints and the sequence of actions. About your generator idea -- the Gray-B-Gon runs on very low power, and my propeller design probably isn't up to driving a real load, like a generator. But, give it a try. There must be a description somewhere of what a high-performance propeller looks like. Note that commercial wind-powered generators have very few, very slim propeller blades.

[extrordinary1]

Thanks for the recent update. My version of this as a wind generator is simply to drive a small dynomotor just like the small generators used for lights on bicycles, but at least cranking out one amp, at 12 volts. This would easily do that. This would allow me to trickle charge my battery while not driving the scooter, as it goes dead easily if I don't drive it everyday. Here in Missouri, it is not uncommon for straight line winds from storms to come through at 60 to 100 mph. Your typical wind generators can't continue to crank power in that stong of a wind. A friend of mine has a very large wind generator with a 3 ft. dia. concrete tower. With his brake set knowing a very storng storm was coming in, the wind snapped his tower. Based on past experience, my 68 inch wind generator using 12 blades made of six strips of fabric, ripstop nylon, survived that very same storm that destroyed his 40,000 dollar wind generator. I'm not cranking out 10 kW like he was, but it works in lower wind speeds his doesn't, and could handle higher winds easier. After he rebuilt it, he had his brake set just before another storm came in. He heard a loud shot, went outside to see what was going on, and he saw a power company truck driving off down the highway, alone. We have net metering here in MO, good luck collecting what you put back into the grid.
The meters clearly mark, plus or minus 20% accuracy... he eventually noticed that shot, took a large chunk out of one of his 3 blades. His brake has been set ever since.

I like the idea and how you presented this potential, as I may use it myself if I return to a rural lifesyle. Nice job you have done here.

[Larry Breed]

Correction to step numbers: The helpful image is now in step 21. Steps 22 and 23 describe the constraints and the sequence of actions.

[extrordinary1]

Thanks for the reply. I especially liked the pattern you used, but I plan to make it from stainless steel up to a 6 ft. dia. I'll have to design a strong hub for it, and I plan to build my own brushless AC generator. I mostly liked the appearance of your blades and wanted to scale them up for my project.

I'm working on one now that has 12 blades of flashing secured to a hub and an outer ring that is 3 ft. dia. The last one I built stood up to 70 mph winds, but when the micro burst hit us at 100 mph wind, the blade assembly came off and I found it two blocks away, undamaged. Needless to say I secured it stronger after that. I liked another guys 3 bladed design, but he used pvc and I don't believe it will take the stresses of storms we get here in Missouri. I can see that small section with only two bolts snapping under stress. I would be hard pressed to be able to bend stronger metal brackets in a shape that would strengthen them along the vertical axis of the blade assembly.