On Thu, 21 Oct 2004 10:22:04 -0700, engsol
wrote:
I bought a new prop for the boat. The instructions said to make sure
the taper of the shaft and that of the prop matched.
75 to 85 percent contact area was suggested as a minimum.
I dry fitted the prop to the shaft,
without the key, and rotated the prop a few times with the shaft fixed.
It was easy to see that I had good contact at the "big end"...maybe
30 % contact area.
My plan is to use valve grinding compound to lap in the taper for a
better fit. My question is: what grit should I use? My instinct says no
larger than 200, and no smaller than 400.
Do you folks lap in new props, and if so, how do you do it?
Thanks.
NormB
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Sounds like the prop may have the wrong taper for the shaft. If the
taper is correct, little or no lapping should be required.