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Date: Thu, 27 Jul 2006 11:20:11 -0400
From: Ernest Christley <echristley@nc.rr.com>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Inconel
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WRJJRS@aol.com wrote:

> Al,
> The strobe idea is a good and useable idea and deserves positive 
> feedback. Any idea that can be implemented by those not in possession 
> of a physics lab are great ideas.
>
Get an adjustable strobe from RadioShack or its ilk.  About $20.  
They're cheap, because they're not powerful, but you don't need a lot of 
light.

Yes, the prop is dangerous, but you don't need to stand next to it to 
see what is going on.  The RatShack strobes have reflectors that direct 
the light.  Do the test at night, and just hold it over your head as you 
stand a few feet away, slowly adjusting the flash rate.  Don't just pay 
attention to the muffler.  Fuel lines, motor mount members, skin panels, 
alternator brackets...lots of things will vibrate from a little to "oh 
my!".  Some you may not care about.  Some may send you running for a 
reinforcement. 

Here's an idle thought that just popped into my idle head.  Knowing the 
flash rate that the muffler is vibrating would easily lead to it's 
natural frequency...which could then be used for some effective muffler 
designs?

-- 
         ,|"|"|,              Ernest Christley       |
----===<{{(oQo)}}>===----    Dyke Delta Builder      |
        o|  d  |o        http://ernest.isa-geek.org  |