[NSRCA-discussion] Metal Servo Arms

[vicenterc at comcast.net]

I am using one in my 100 cc gas engine.  It works great.  The problem is that it is hard to prove that works.  

--
Vicente "Vince" Bortone

-------------- Original message -------------- 
From: Bob Richards <bob at toprudder.com> 

Earl,

You are right about soft mounts. One thing I don't understand is why soft mounts have not made much progress in the larger 50cc+ size planes. 

Bob R.


Earl Haury <ejhaury at comcast.net> wrote:
Bob

I agree - in reality servo arm / spline strength is pretty much of a mute point for pattern. I did the tests after a friend broke an 8411 shaft on a big gasser, and some heli friends claimed the Al arms stripped the spines from nylon servo shafts. Takes excessive force to do either. 

Recall changing a clevis to a ball link on a Rossi carb arm - arm broke on the first flight, a doubled arm broke on the next - back to a clevis and never broke another. Vibratory forces aren't understood by most - but experience is a great teacher.

Somewhere I've some DSA data gathered with mini-accelerometers mounted on aileron servo mounts, firewalls, etc. One look at those data with and without a soft mount will make one a believer in soft mounts!

Earl
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From: Bob Richards <bob at toprudder.com>
Subject: Re: [NSRCA-discussion] Metal Servo Arms
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