Measuring mast rake?

[John Hubbard]

I'd like to reduce the rather strong weather helm on my old H20. I know that reducing the mast rake will have the desired effect. The question is this: Do I simply assume that the boat, sitting in the water, is level and measure the rake of the mast relative to that assumed standard? Using a carpenter's level against the mast, or the main halyard as a plumb bob, and easily tell that the mast is raked aft quite a bit, assuming that the boat is level.

 

[Guest]

Assume a flat non-rotating earth.....

I had problems that started out that way in school and always thought it was funny. Just use your main halyard and a weight. it'll be close enough.

 

[John Hubbard]

OK, I'm retentive...

Yeah, I'm an engineer. Used to do Saturn V flight simulations - with a rotating earth model, atmosphere, wind shear and gusts, etc....

 

[Mike Epp]

3,4,5 triangle

I likewise wanted to reduce the rake on my mast cause it seemed to be excessive but found that the forestay turnbuckle was as tight as I could get it. Also noticed that the boat definitely sat high on the bow end. So I checked the rake by measuring a 3-4-5 right triangle from the mast to a pipe laid across the cabin top. In the end I compared the angle of my mast with another 23 and they looked parallel. Helm seemed to be OK to so I left well enough alone for the time being.

 

[Greg Stebbins]

Sorry John, I couldn't resist....

John, I get the same way sometimes. Too many interacting variables.Just do an initial set-up at the dock and call it 00:00:00:00 (fore,aft,port,starboard). After that, trial and error with good notes counting turnbuckle rotations and helm effects.