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Subject: RE: [FlyRotary] Re: 2nd battery Re: Amps required to run engine & amp- hours available
Date: Mon, 21 Feb 2005 15:47:53 -0800
Message-ID: <091A2D42FAF91A41B84750D269FC97E72B3118@canformail1.canfor.ca>
Thread-Topic: [FlyRotary] Re: 2nd battery Re: Amps required to run engine & amp- hours available
Thread-Index: AcUYU8t6W6dZbyaNTdOUM0vL3Xtp2QAGfq6A
From: "Bartrim, Todd" <Steve.Bartrim@canfor.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>

I'd like to see this idea succeed, as while I'd love to have a small PM
alternator as a back-up, I won't do it if it is belt driven at the same
end as the main alt.
	A few years back, somebody on the list was considering
fabricating a small pulley to fit in between the flex plate on the PSRU
end of the engine. This would obviously be a real pain to change this
belt, but would be IMO much better than having to belts driven by the
front pulley. I don't know if anything ever came of this.
	Another suggestion was made to use the stator from a 2-stroke
engine, mounted directly around the shaft. Since I just happened to have
a spare one for my snowmobile from years ago, I looked into this, but
decided that it was just way too much modifications to make it work. Now
they are selling waterpumps that have a built-in alt using this same
idea and I can't help but thinking how sweet it would be if I could do
this. When I originally looked at the possibility I was considering the
front end, but now I'm going to take a long hard look at the possibility
of mounting around the shaft at the flex plate. I doubt that there is
anywhere near enough room, but it's worth looking into.
Todd


The alternator that is 80% efficient and is pushing 50A requires just
about 1Hp.
What I've seen of the gears, unless they're made of pot metal, I don't
see how they couldn't be stout enough.  I haven't rebuilt my engine yet,
so I'm going off drawings (probably not to scale), and measuring the
gear on the CAS.  I think I calculated the torque at considerably less
than 10in.lb., but I'd have to find the napkin that I calculated that
out on 8*)