SET UP. E
C B
D
A A MATERIALS [A] Pint-sized Mason jar with extra screw caps and lids
[NOT SHOWN] Package of long fireplace matches, or a long-handled barbeque lighter Table salt (optional)
[B] 22- to 26-gauge magnet wire (thin enamelcoated copper) [C] 1½" to 1¼" copper drain/waste/vent (DWV) reducing fitting [D] 1¼" to 1" copper DWV reducing fitting Available at home centers or hardware stores. These two pipe fittings are for the conical air diffuser. [E] Small bottle of methanol Available at auto supply stores as gasline antifreeze; common brands include Heet and Pyroil. Methanol absorbs water readily, which is why it works well as gas-line antifreeze. But this property also causes it to go bad quickly, so you should always use fresh methanol.
Boric acid crystals (optional) 1' long, 1" diameter plastic or metal pipe (optional) Optional items are for experimental variations.
TOOLS Electric drill with ½" and 1" drill bits Wire cutters File or sandpaper Teaspoon measure Cookie sheet Refrigerator/freezer Safety glasses
A
SAFETY GUIDELINES This is a jet engine you’re building, a tempest in a teapot. I’ve never had any problems with this design, but no one — not me, not this magazine — can guarantee your safety. If you do choose to go forward with this project, here are some important safety measures. 1. Do not experiment with different sized jars and openings. A too-large jar with a too-small opening might result in an explosion of glass shards. 2. Use no more and no less fuel than directed. Wipe up any spilled fuel immediately. 3. Use only the parts listed in the directions. These are proven to work safely, and I haven't tried or analyzed all the substitutions that people might think of. 4. Wear gloves and safety glasses or goggles. 5. Do not handle the jar for 5 minutes after a successful run, and then be sure to tap it first to make sure it is cool enough. The Reynst combustor is an extremely efficient heating device, and it gets hot enough to burn skin after just a few seconds of run time. 6. After a long run, the glass jar may crack. If so, carefully sweep the entire assembly into a bag without touching it. Seal the bag and throw it in the trash. Jars are cheap enough, so just get another one. 7. Keep spectators at a safe distance. 8. Always ignite the engine with a long-handled match or barbeque lighter, to avoid getting burned by the pulse of hot gas that immediately follows ignition. 9. Examine all parts for wear before and after use. Discard any worn parts. 10. Always use common sense before, during, and after running the jam jar jet.
Gloves
Make:
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11/30/05 8:30:48 AM