December 24, 2001
Samuel Falvo II sent us these pictures of his PT-3 with comments following:
Click on photo to view full size
Sun Dec 2 04:02:53 2001
"I was perusing your website and found that you had what appeared to be a nice combustor and an excellent turbine setup ready to be mated. Excellent news! I thought I'd jump in there and let you know that, with my exorbitantly extensive resources available to me, I have created and finished the third paper model turbine: the PT-3.
It's a 4" diameter turbine with roughly 1/3rd of its active area ported for exhaust. The rotor assembly is constructed of a stack of 8 4" discs spaced roughly 1/32" apart using paper spacers (which double as "rivets" in traditional metal designs). The shaft is a plastic soda straw.
The rotor housing is an octagon (the best I can do with corrugated cardboard to approximate a circle) in shape, and has ports for exhaust and intake.
The bearings are raw -- the plastic soda straw just threads through some holes in the cardboard. However, these holes have been primed with graphite from a #2 pencil for lubrication.
Results? I've *floored* everybody I've shown it to. Using breath power alone, I've gotten it to spin up to around 3000 RPM or so (based on the note it produces relative to my car's engine's note). My mechanically inclined friends try to put a load on the turbine by grabbing the straw. If they grab hard enough, of course, it does manage to stall. However, they're reaction every time is, "Holy $#!+! This thing has a *lot* of torque!"
Keep in mind that this turbine has to overcome all the friction of paper-on-paper too! Just imagine what it'd be like if it sat on reasonable ball-bearings.
My co-workers at the office always are playing with it. I know of several people here at the office who have their own straws just so they can blow into my rotor housing and make it spin."
Questions? Comments?
prieli@up.net
Last updated: 03/27/02 01:02 AM