Convection Powered, Counter Rotating, Kinetic Sculpture

Powered by Sterno made of wood, sounds like a recipe for fire. It took two cans of heat to get it moving the first time but continued to spin almost as fast after removing one can. It serves no purpose yet but tomorow I'm going to add a pot- pouri jar just under the rotor blades to give it
 reason for being. I'll call it counter rotating pot-pouri diffuser.
I'm working on downloading a driver for my video cam so you can see it in action.

I 

Materials used:
1/4" x 5.5" x 48" poplar
.037" x 12" x 24" birch plywood
1/2" x 5.5" x 24" poplar
1- 4" long shawl pin
4- 1/8" plastic beads
JB KWIK WELD
Titebond III wood glue
1- Corel saucer

Tools used:
Epilog laser (other methods of cutting are possible)
cordless drill
small paint brush
small vise grips
small spring clamps
small square


                      


                                                                              
 

I built a jig to assemble the rotor rims using a very flat support board, a 1/8" thick plywood circle the inside diameter of the rotor's 1/8" plywood rings. Made a clamp from 1/8" plywood to hold the .037" thick birch plywood to the 1/8" rings. When gluing up everything stay flat and tight. Very little pressure is needed on the visegrips to hold the .037 " plywood tight.

Notice the small tabs on the rotors (tips of pencils), the rotor hubs need to be glued so the rotors are mirrored.

I drilled a hole into my build table ( square with the surface) so the hubs would glue up square.

The rotor blades are quit thin and very flexible. To assemble them I simply twisted each blade to lock the two tabs onto the 1/8" plywood ring, one tab over the ring, one tab under. I mirror imaged the rotor blades so they would spin in opposite directions. Tension holds them in place, no glue is needed.

I attatched the support body halves to my build table so when I glued up the ribs and stringers they would remain straight.

Gluing on the ribs I used a square to insure they wre too.
note: if you cut with a laser the glue faces need to be sanded square.

I used a small pair of vise grips to support the axle and rotor assembly while the JB WELD cured. 

Finish by gluing the support to the base and fit the saucer to hold the Sterno can.