Hi Andy,

At 09:41 AM 10/29/98 -0500, you wrote:
>Have you ever been to a speed shop?  You need to get your tires balanced
>for operation at the expected speed.  Harmonics.

So, you're saying that they actually listen for harmonics generated by the
wobbling? I would think that the wobbling would be at the same or less
frequency then the rotational frequency of the object.

>
>Oh, it does!  When you're spinning at 60K RPM especially.

Andy, are you using jet powered boats? <G> I have never heard of a model
engine that spins a prop at 60,000 RPM in AIR let alone WATER!!!!!

I have an RC plane with a .40 cu in engine and it tops out at 16,000 RPM
with a 10x6 prop (well, I never measured it, but that's what the specs say).

>
>You can be perfectly balanced dimensionally (same outline both blades) and
>statically (it stays level on the balancer), but until you spin it you
>don't know for sure.

Well, I have never worried about anything other than static balancing on my
prop. The only other way that it could be unbalanced (as far as I can see)
would be if there were more mass toward the back of one blade and toward
the front on another. If you get this advanced, how do you adjust your
props? I just sand the outer edge of the flat side of mine to remove moment
from that side.

Sean


>
>Andy
>
>==================================================================
>Andy Kunz - Statistical Research, Inc. - Westfield, New Jersey USA
>==================================================================
>
+-------------------------------+
| Sean Breheny                  |
| Amateur Radio Callsign: KA3YXM|
| Electrical Engineering Student|
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