Posted by ovyyus (150.101.145.242) on September 23, 2003 at 18:01:03:
In Reply to: Message for Michael posted by grim on September 23, 2003 at 13:24:57:
Hi grim,
Great description - thanks!
We know Bessler's early uni-direction design (self starting) required 'tying up' or immobilising when not in use and could also function at any speed from stationary up to its maximum RPM (eg: Bessler allowed adjustment of a 'bolt' in the axle which controlled speed). That being so, it's obvious that his uni-direction design would allow the wheel to self rotate very slowely if desired - say 1 RPM.
Question: Rather than allow your design to freely rotate (you say accelerate?) to its destruction, why not limit the maximum speed of the structure and therefore limit its inherent destructive forces? Simply holding the wheel in your hands and only allowing it to turn very slowely would prove that it can create a constant overbalance over many cycles and negate the destructive forces encountered with its uncontrolled free-running speed.
If the design exhibits a constant overbalance, why not just operate it at very low RPM to avoid generating all those destructive forces? Walk first, then run.
Regards, ovyyus
: Mike
: I must apologize if my reply to you came off as a slam or burn. That was not my intention at all. Unfortunastely your message got caught between two trains of thought.
: If your intentions were simply to inquire or offer advice, curiosity, etc., then please except my sincere regrets in the way your answer was sent to you.
: What do I know...well, after looking at Honnecourt, the early Indian and Arabian designs, etc, it occurred that they were all the same; trying to put more weight on one side
: of the axle than the other, resulting in always more weights below the axle then ever above, which made the wheel bottomheavy, like the unicycle rider/string toy whose low riding weights keep him from flipping over off the string he rides.
: So an image was scanned and inverted, which yielded weights lifted off the "bottom" of the wheel.
: According to what could be seen, the wheel now had more weight above the axle, and was therefore topheavy and unstable. This was a "flaw" all those machins had that had been mentioned
: long ago in a post. The trick was to make gravity do all the weight-lifting operations. Levers, trip pins, etc rob energy in their operation; for this to succeed, the only way was to use levers and
: counterweights directly on the weights themselves, so gravity grabbed the small counterweight and through the second class lever raised the larger weight of the bottom of the wheel and held it there, with the wheel's only
: involvement being as a mount for the large weight's pivot point, through which the COG changes were transferred to the main axle.
: Timing of lift was slow, so small posts and springs were added to the system, to assist the counterweights in lifting the large weights at the proper time. The correct setiongs were by experiment.
: When all was completed, the whole assy was released, and it took off on its own. The lower weights were striking their stops quite hard, if you count "one-thousand-and-one" as a second's worth of time, they were striking
: at a rate of one raise/hit per syllable. Lost the springs. Reattached, same thing, this time one of the counterweight levers shifted also. Dissasembled, bolted them both tighter, ran
: again. Gave up when they hit so hard that they egged the bolt holes in the 1/2" plywwod disk at their stops.
: Smithy's just flat cracked the disk he was using, finally, also at the stop points.
: I believe, after thinking, that weights trying to drop on the top release side at 32ft/sec/sec around a 15"
: disk may have definitely contributed to the problems. Brett suggested four weights, two on each side, might smooth
: it out, but it was finally opted to try a different approach.
: Five-six turns is all that could be achieved before the construction let go. But it did start from a standing start
: and passed two turns easily from its start, so maybe you're right. Might be worth building a bigger, heftier model,
: feet instead of inches diameter.
: This i