Mono Turn Fin Q's

[Ctonez]

I've asked this Q on a couple electric boards, but really not much response.

I have a Toysport Triton without the flood-chamber. It has speedmaster hardware.

I've been studying setups I've seen online and I've noticed some interesting variance in the angle at which the turn fin is mounted.

I've read the Glen Cuprit and John Finch articles several times, but they don't really touch on "Mono" turn fins with any depth.

On my setup plans from Joseph Toth and in photos of many European Tritons the turn fin is vertical and parallel to the rudder.

My understanding has been that the fins should be mounted at a 90 degree angle to the transom...however, the Triton does have a thin flat ride pad like the No Step hulls...which caused me to wonder if they are mounting the fin @ 90 degrees to the ride pad?!?

Could this cause the boat to turn with a more "upright attitude" instead of allowing it to roll over further before an angled fin would contact the surface?

What are the differences in handling characteristics when using either option?

thanks for any help in advance.

-Corey

 

[lohring]

The mono turn fin should be mostly out of the water when the boat is upright and running on the keel. The fin is used to keep the transom from sliding out when the boat leans in the turns. It will be more effective if it is 90 degrees to the bottom.

Lohring Miller

 

[John Finch]

I agree with Lohring. The turn fin is only for when the boat is leaned over to turn, so why not have it vertical to the water when cornering. I have used the fin straight up and down (parallel to the strut) in use where the boat does not lean over for a turn. That setup is best for a shallow vee boat that does not lean over. And for the same reason. You want the fin to be straight up and down in the water when you turn. Some of the 30 inch Twin crafts worked well with the straight up and down fin because the hook on the right strake kept the boat level when turning. So...............It basically depends on how the boat leans for a turn. It's that simple. If you want to make a boat turn better that has a fin, other things like rudder location and trim tabs can affect turning as they also control the boats actions as the boat hangs on the fin. In other words, it ain't all about the fin.

 

[Ctonez]

thanks for the input guys...definitely appreciated.