I have found the rudder trim in my Maule (such as it is) really useful, especially on long climbs. In addition, depending upon speed, I have had to fiddle with the setting to get things where I like it. If you aren't familiar with the Maule rudder trim, it is essentially a handle you tug on that just pulls on your right rudder pedal with a spring. Dead simple. Also, right trim only
Since I am putting an electric elevator trim in my 4pl (actually, a G3X system with AP and YD), I had the trim wheel left over. Not wanting to have a rudder trim tab sticking out the back of the airplane and only being trimmed for one speed (unless I have built everything perfectly straight...not likely since this is a scratch build) I thought I would try and design and build a rudder trim system that is completely adjustable.
Here it is.
I have put a red arrow pointing to the trim wheel under the throttle mount.. The wheel is snugged up using an AN310 nut using the right combination of washers to get the right friction so that it can be moved by hand but not by the rudder return springs. NOTE: I know there is an AN365 there right now. It was what I had handy doing the fit-up. It will be replaced after covering...
Here the arrows point to the trim wheel and the rudder return spring(s).
The cable then goes through an upper pulley, travels down the tube, and through a second pulley (just out of view).
And finally the lower pulley and the shackle attachment to the rudder cable assembly.
Probably overkill, but it was fun to make and I am sure that I will use it.