N4NM comments inserted in Noel's text:
> Agreed with everthing except the statement. "...Then make sure the
> collar can rotate around the mast without binding".. Seems to defeat the
> point of having a thrust bearing? Why not have just a collar then?
Lots of us have used pointy-tops with no bearing for years...much the same
as a collar. The thrust bearing (overkill for many of us) just provides a
way to eliminate the gap between the mast and upper tube. Actually, the
bearing DOES rotate with the mast because it's almost always touching one or
two (but not all three) bolts with enough pressure to rotate the bearing.
Only if everything were exactly collinear, balanced and plumb, with no wind,
would the mast not touch any of the bolts. That's the whole point, and the
issue to which my post responded: elimination of potential binding from
misalignment.
> I think the bolts in the thrust bearing should be tightly holding the mast
> or at least very snug. Not bearing weight but enough to support any
> lateral movement.
I doubt that your bearing is unloaded axially, especially if your rotor,
mast and top plate aren't perfectly aligned.
>Your method would cause the bolts to eventually scar
> the mast even though you say the clearance is minimal, unless one used
> shims.
I've seen no evidence of scarring after 4 years.
> I'm curious haw many people who utilize thrust bearings, allow the
> bearing to "rotate around the mast" or make sure the mast and bearing
> are tight and rotate together?
I'll bet almost everyone not only clamps down on the bolts, but supports
most of the weight. That's okay; it's not the first time I've swum upstream!
73,
Chuck, N4NM
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