Now camping solo with the Pooch around Lake Powell, and trying out some ideas using stuff already around. Hence, the Subject name above, tongue in cheek...
The previously-unused, orange Garden Sprayer painted black holds ~2 gallons of Water and hit 110 F degrees in tests at home [w/o Astrofoil], and here in the field over the past 2 days. I got 2 nice Showers out of it before adding water. All stored hot water stratifies, so you have to invert the Sprayer a few times to mix water inside. A classic enameled Coffee Pot can off the Stove ups the temp if you heat and add that amount of water. I use the outdoor probe of an Indoor-Outdoor Thermometer to check water temp. 'Astrofoil', used in our new House, reflects heat onto the Sprayer and cuts wind-based temp losses. My Shower Mat is my SUV Floor Mat, and Sandals keep off the mud. My dark colored SUV makes a great wind block and a warm solar 'wall' to sit against post-Shower.
A pal in Hawaii fills Sprinkler line on a hillside with water. He showers in the early afternoon by gravity feed drop while standing on a Pallet with a view to die for. K.I.S.S.. Water circulated slowly, or periodically, through black tubing on a CT Roof, stored in a Big Box 10 Gallon Heater, or paralleled into an RV Water Heater, would extend boondocking w/hot water.
Everything from a Coleman Gas Lamp hanger to a Painter's Plastic 'Tent' off the SUV Hatch to my Radio Antenna mast to my clothesline is made from 1" PCV left over from an automated Cistern I built. It all pins together in various configurations with 'L' bits of bent coat hanger, or with Velcro strap to hold things to the SUV Roof Rack. I'm using the same Car Topper as 'Navigator' above, and sleeping in the SUV back using spare bedding and Astrofoil underneath. Below-average seasonal temps are 32 at night and 55 daytime, not reflected accurately in the Gauge above in direct Sunlight. I made a Table from 1 x scrap that bungees to a drop Hitch mounted upside down. It's notched to prevent lateral movement on the Bumper. Clean 5 gallon Buckets retrieved roadside over the years serve as storage, hauling, and a second horizontal surface when placed on top of a 5 day Cooler, topped with a Cutting Board. I'm trying to get double duty, or more, out of everything.
A Thai fellow posted on line his use of a metal Garden Sprayer, and I simply painted ours black for Solar use. A metal one allows Stovetop heating; a real plus.
Alstrom Point is where most Lake Powell pro pix are taken. Stunning, 'Road Runner' country with more friendly Int'l Touristas now in town than I would ever have thought. Being clean while Boondocking rocks! A 'Cobra' 115 VAC Inverter run off a Deep Cycle Battery laying around charges many toys. A Verizon Aircard to the Cell Tower on Navajo Mountain [in the pic background] makes connectivity and pic processing/forwarding happen while keeping tabs on my aging Father.

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