I had a Hassler many years ago. It took us half way across the Atlantic then broke a weld due to extreme
weather helm in a strong
wind gust.
It was the type with the vane rotating round a vertical axis, these days horizontal pivoted vanes are usually prefered.
If you have specific questions I might be able to help, you can private message me. I also have expertise in control systems.
I recommend you rig it enough to go out and try it and see how it responds, then make adjustments accordingly. Every
boat is different.
------------------------------------
"Desperate Deliveries" and "A Small Slip" by Cris Robinson available on Kindle ebooks.