[TowerTalk] Thrust Bearing...

[Jim Lux]

On 1/6/13 8:02 PM, Grant Saviers wrote:
>
> My 2 cents, having two HDX589s and a TMM433.
>
> I don't think you need a thrust bearing, if your tower has the welded in
> sleeve for a 2" mast. I think this is standard on all the current UST
> crank-ups.
>
> The sleeve will handle side loads well beyond the TX438 rated wind load
> and your rotator will handle the weight load.
>
> I had a TB3 on 85' of Rohn 25 a while ago, and it failed.  If you don't
> have a sleeve and need a bearing to handle side (radial) loads then I
> think boring a mast sized hole in a top plate of 2" thick MDS Nylon
> (Nylatron GS) or UHMW is a better approach.  A polymer sleeve bearing
> will last a long time at the antenna rotational speeds and loads and
> requires no maintenance.  Both materials are UV sensitive, but not much
> of a worry in 2" thickness, or just paint them.  I've found remnants on
> ebay at good prices.
>


White poly cutting boards. Stack em up, run the hole saw through them, 
and you've got a great low friction, low speed *radial load* bearing 
(which is really what you want, anyway). (actually, I suspect a single 
layer is good enough)

http://www.target.com/p/kitchen-3-pc-cutting-board-set/-/A-510239#prodSlot=medium_1_3

http://www.target.com/p/chefmate-poly-cutting-board-white-14x17/-/A-10219387#prodSlot=medium_1_16


http://www.walmart.com/catalog/product.do?product_id=13397991&findingMethod=rr