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Posted to rec.crafts.metalworking
Glenn Ashmore
 
Posts: n/a
Default A geometry/trig problem about compound angles.

Working on the steering cables for Rutu and have run up against a math
problem. The steering lines come off the drum down through the pedestal to
a pair of sheaves. To avoid wear the lines have to be aligned very
accurately to the sheave grooves. In order for the boat to turn the same
direction as the wheel the lines have to cross inside the pedestal so the
sheaves have to be canted outwards from vertical about 6 degrees to make the
lines run fair. BUT the lines lead off from the pedestal base about 15
degrees to the left. It looks like when I angle the sheaves in the
horizontal plane the angle of the cant changes. .

How do I calculate what the actual cant angle should be before I start
welding this thing together?

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com