I did not buy my tower with the US Tower bearing included. Instead I
installed a different bearing. The top plate is welded in place. As a result
I ended up fabricating a plate the bolted to the existing top plate. The new
plate was drilled for the bearing and bolts for the new bearing welded into
the new plate so that the two plates would be flush when assembled.
The center hole was adequate for the larger mast.
Depending on the bearing it could be that you might drill additional holes
in the top plate for the new bearing. It is a bit hard to drill large bolt
holes with a hand drill however.
> -----Original Message-----
> From: email@example.com
> [mailto:firstname.lastname@example.org] On Behalf Of Jim Thomson
> Sent: Thursday, February 18, 2010 3:56 AM
> To: email@example.com
> Subject: [TowerTalk] Thrust bearing options for HDX-689
> I'd like to know how the top thrust bearing is configured on
> the US Tower HDX-689. Specifically, can a 2" thrust
> bearing set up be swapped out for a 2 7/8" bearing ??
> I'd prefer to use a 2.875" thrust bearing [hole size is
> actually 2 15/16"... or 2.9375"]. Can this be done ?
> Can the top thrust bearing plate be swapped out for a
> different one to acomplish this ?
> Or is the top bearing plate already welded on ? I
> hate 2" bearings /masts.. with a passion, but if I'm stuck
> with it, that's all I can do.
> I bougth a used HDX-689, which comes with a 2" bearing set
> up. The tower has not been delivered..yet.
> Tnx.......... Jim VE7RF
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