Horizontal or Vertical axis wind vanes

[GILow]

Hi all,

I've completed the build and installation of my auxiliary rudder with trim tab for my DIY wind vane. The rudder is loosely based on the dimensions of the hydrovane rudder, but increased in size by 30% in deference to the issues I have read from a number of users of the Hydrovane who felt it was an excellent bit of kit but a bit undernourished in the blade department for boats of my size and weight.

I have the raw materials ready to start making the vane part of the system, and I was planning to build a horizontal axis vane with variable axis inclination, based on my extensive reading of many, many internet articles and books on the subject of windvane activation.

Now, making a horizontal axis vane is going to be no small task, and I am expecting it to take many hours and many iterations to get right. So when I spotted a vertical axis semi-amateur built wind vane on another thread that has given very good performance, including in the dreaded downwind mode, I started to question my assumptions and reading about the need to go horizontal.

This is a call out to users of wind vanes, commercial or DIY, to share their thoughts on the pros and cons of vertical vs horizontal axis performance.

For what it is worth, this is going on a heavy (17 ton) 42 foot cruiser with a 3/4 cutaway keel and keel hung rudder. The auxiliary rudder has been built and installed but not yet tested. The auxiliary rudder has an 80/20 balance and has been fabricated to be very easily demounted from the stern, not that this should affect the choice of vane but it is worth noting that the need to deal with coming and going in the pen or close quarters maneuvering is not an issue.

Comments on the pros and cons of each style of vane warmly welcomed.

Matt

[Jim Cate]

Matt, we've been over this before, but I was satisfied with my version of the AutoHelm inclined axis, variable angle vane driving the trim tab via push-pull cables. IMO, much easier to design and build than typical gear and shaft linkages.

Worked for me, and has worked for lots of folks with the commercial AutoHelm gear, still manufactured by Scanmar in the USA.

Jim

[GILow]

Originally Posted by Jim Cate

Matt, we've been over this before, but I was satisfied with my version of the AutoHelm inclined axis, variable angle vane driving the trim tab via push-pull cables. IMO, much easier to design and build than typical gear and shaft linkages.

Worked for me, and has worked for lots of folks with the commercial AutoHelm gear, still manufactured by Scanmar in the USA.

Jim

Yes, their design for the horizontal vane is very elegant. I'd forgotten about it. And like them, I intend to use bowden cable connections. I have some good quality teflon coated cables left over from my bike building days.