My first Tricopter started life as the simple wooden framed Mongrel Gear Trilogy
using 4 cheap rate gyros, 3 cheap ESCs, 3 cheap motors and the RC Tx's CCPM mix.
The rear motor was mounted on a platform supported by a heli blade shaft and pivot
which is a popular option for Tricopters.
However, during the learning process (having never flown any rotor-craft before), I
found that any crash on the rear arm bent the heli blade pivot. In fact any
hard landing would do it as the weight of the motor simply bent the shaft down.
That meant the yaw trim changed constantly and eventually the shaft just
snapped off.
I rebuilt the rear tilting motor mount using steering parts from a crawler
so that it was a tilting platform with the pivot point directly over the center
of the rear arm. That mount is totally cobbled together with zip ties
but it has been absolutely bulletproof. I tweaked the servo position but otherwise
transfered that mount over from old frame to my new one, unmodified.
It wasn't long before I was buzzing around low between and below trees, over water,
etc. Accumulation of crashes including an inverted water landing went through
the first batch of motors pretty quickly. When I got into the 2nd batch
of motors (and some ESCs) ordered from HK I found some un-subtle differences
in power. I was having to use a-lot of trim to get it flying level. Problem is,
that wasted precious flight time, and if I tried to leave it trimmed when changing
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