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Date: Fri, 20 May 2011 17:24:44 -0400
From: Ernest Christley <echristley@nc.rr.com>
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To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Blower experiment:  FAIL
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I doubt any amount of balancing would have kept the blower together.  
The highest RPM I hit was aroun 4000.  Most of the rivets were sheared 
cleanly.  My design was simply not anywhere close to robust enough.

I've got a line on a company that will do one-off dynamic balancing in 
North Carolina.  Do you think I could convince you to mill me a rotor, 
and then I could get my whole assembly balanced?


H & J Johnson wrote:
> Ernest, did you get a high speed dynamic balance on your blower?  I've 
> built blowers of a similar form and had good results, but only after 
> balancing to rated RPM.
>
> Jarrett Johnson
> www.innovention-tech.com
>
>
> ------------------------------------------------------------------------
>
> Some of you may recall my blower experiment.  Using the shaft between 
> the flywheel and PSRU to drive a centrifugal fan to charge the intake.
>
> My implementation died in the crib.  before.jpg shows what it looked 
> like a week ago.  after.jpg is what was left of it after the few 
> minutes I was able to get the engine to run.  Well, that wasn't all 
> that was left over.  intake.jpg shows how the blades got thrown toward 
> the intake and smashed up against the air filter.
>
> Oh, well.  Until I can design and build or have built an impeller that 
> can handle 8000RPM, I'm going to table this experiment.  I still think 
> it is a good idea.  So did these guys:
>
> http://www.flightglobal.com/pdfarchive/view/1942/1942%20-%200142.html
>
> Furthermore, the calculator at 
> http://www.forestryforum.com/members/donp/Blowercalc.htm indicates 
> that with the 10.4" diameter, 3.35" deep area available for me to put 
> a blower, I should be able to generate 17" water column pressure.
>
> ------------------------------------------------------------------------
>
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