Well, a teniometer is generally used to read tension in a cable. If a
fin changes its angle to the flow, it's going to act like a rudder.
You're right, I think I'd need to see the system - or at least some
drawings or photos - to have a clear idea of what you're looking for.

(Doug) wrote in message . com...
Thanks Corrie, I think that is what I need to get started. As for the
best location, well, I've never done this before so I don't know. But
there are some options. One problem is as the rudder comes up, the fin
changes angle to the flow, but I think I have a handle on that one.
The other is, we don't want the fin to raise the rudder any more than
"all the way up". You would have to see the rudder and all the
brackets to see what I mean. Anyway, thanks for giving me some ball
park figure. Now I need a tensionmeter, something I can hook to the
rudder and get some exact "pounds of pull" readings. Anyone know where
I can get a good cheap tensiometer? that reads 0-20 lbs?

(Corrie) wrote in message . com...
What do you mean by "best location?" Best in terms of ...?

I'm not a hydrodynamicist, but I'm pretty sure that the standard
equation for dynamic pressure would work: density x (velocity^2/2).
http://wright.nasa.gov/airplane/bern.html