[TowerTalk] 3" mast thrust bearing alternatives

[Jeff AC0C]

I’m looking at a 4-bolt flange bearing for use as a thrust bearing on the top of my tower.  Trying to avoid the Rohn bearing.

My mast measures 3.005 OD.  I can find a lot of 3” flange bearings but NONE of the web pages mention anything about the actual bearing hole ID.  They just say 3” shaft without any comment as to the tolerance range of the shaft.  So if the hole ID is 3.020 then it will fit nicely.  If the hole id is 3.005 then it’s going to be a problem. 

For my 2-1/8” mast, I just used a 2-3/16 bearing and it was perfect.  But for 3” – looks like the available size ranges are few in number with 3.25 being the occasional find.

Appreciate comments.  Thanks!

73/jeff/ac0c
www.ac0c.com
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