This subject popped up on another forum. figured it was actually worth writing a dedicated post about it here.
WE all know that you can use a 3 pin plug prong to make a little tiller arm.. they arnt bad but they are chunky, and not always suitable for the job,
A method i use, especially on things that go very fast and loosing your rudder function is
NOT an option is to make up a plate tiller arm..
Very simple to make, all you need are strips of 6mm wide 1mm brass, nut bolt and 2 washers (m3 work best), + 1 drill bit to the same size as your rudder shaft (or what ever you wish to move)
First thing to do it just to simple mark up where you want yout bend to start you need some material to fold over the bottom.
Simply fold over one edge of the brass over the bolt, this will give you the form which holds the bolt and nut, next mark just up from the bolt the entry point for the rudder shaft and drill it out to the right size through both levels of the brass,
YOU much ensure that the rudder post will slide through
WITHOUT touching /fouling the bolt, but it be VERY close 1/2mm is best!
Next just cut a slot in the bend to meet the hole you just drilled out and widen it slightly with a file, you want at least 1mm of gap.
Then just drill a series of holes up the length of the arm to suit your needs. these arms can be as long or short as you like!!
you can shape it later once happy with it.
To fit it.. just slip a nut and bolt with some wasters each end through the folded edge and slip it onto the shaft through the drilled hole, then tighten up the nut and bolt.
The slot you cut will allow the brass to flex enough to actually dig in and grip the shaft.
Simple, cheap, no threaded grub screws, no rusted grub screws, easy to actually do up tight. I've never lost a rudder or rudder function through using one of these, but i have with 'shop purchased ones!''
The photos below are the exact same method but used an M4 nut and bolt with 8mm wide brass strip (as these going on a boat which has an M5 sized rudder arm)