March, early

Had hoped to have calliope #4 done in a final rush job, so that I could take it to Sunday’s Maker Faire auditions in San Jose, but it just wasn’t in the cards. There’s just too much work to be done, to wit: it took several days to organize a paint job (powder coat gloss white) for the manifold and. once I had it back home, I still had to build something to allow me to tune the bells in a more efficient way (ha ha) than the air compressor method. And once that was done I had to do the tuning, which meant another set of fixtures so that I could do quicker bell mods on the lathe. Bottom line: I didn’t even finish tuning of all 12 whistles until Sunday afternoon.

Delays in getting new circuit board caused by various emails being trapped in my graymail filter means I won’t have the way kewl new circuit boards that Kris Magri designed for me until the middle of next week.

Anywayyy with a little luck I’ll have the bugger working by this coming weekend, whereupon I hope to create a clean spot on the workbench (!!), then I’ll add a roll of gray paper for a nice neutral background. Then I can make a decent video of the finished contraption in action. I’ve decided on a name for it too: Calliopus Minimus; whaddya think? Photos of latest work follow.

Whistle Blower Box

Photo #1: The whistles now need very little air to toot; no more than 2 to 5psi. It was impossible to reduce the air compressor output properly so I built this plywood box as a plenum that could supply HVLP (High Volume Low Pressure) air from the ass end of a vacuum cleaner. I added a 0-15psi pressure gauge but I never got the needle to move… The assembly in the foreground shows the inside of one of the frequency adjustment sliders I devised. These allow me to increase bell length, necessary when I switch from cold compressed air to hot propane and steam. Clamping ‘nut’ is circular ‘ so it won’t fall out of the slot if it rotates.

Backwards Vacuum Adapter

Photo #2: Other end of the contraption: this particular vacuum cleaner didn’t have an exhaust port that the hose could easily plug into, so I had to make one. I welded up a mini-plenum out of steel scrap but the force of the vacuum kept blowing it off of its seat. I tacked on a shelf, then flopped a buckshot-filled exercise weight (the blue thing with the black stripes) onto it. What makes this vacuum particularly kewl is its variable speed motor; i.e. a variable pressure. 

Kris attaches last tuned whistle

Photo #3: Kris Magri, designer of the Parallax Boe Bot, dropped by and helped out, screwing the last tuned whistle into its solenoid valve on the manifold. It was cold in the shop, too!

Whistle Assemblies

Photo #4: Shot of several whistles and their solenoid valves on a section of the painted manifold.

Assembled, awaiting Electronics

Photo #5: The whole magilla lacking only electronics, computer, air compressor, some sort of base, a power supply, wheels to make it mobile, etc, etc.