[TowerTalk] Frozen Rotor

[W0UN -- John Brosnahan]

>
>
>Between the sleeve and the mast, I use a fhin piece of polyethylene sheet 
>cut from one of the new "disposable" cutting boards they sell in Walmart 
>and supermarkets. To prevent wear, I wrap it around the mast and cut it so 
>it doesn't overlap, then slide it in between the mast and the sleeve to 
>act as a bearing. I checked it after a year and there was no noticeable wear.

Jerry, clever idea.  Most of the cutting boards I have seen are made of
UHMW (ultra-high molecular weight) polyethylene which is also used for
bearings. I have heard that they are used in the trucks (wheel assembly)
of railroad cars.

I have made my own bearings from UHMW by sawing a square piece
of one-inch thick stuff to size and drilling it to the bolt pattern for a
Rohn TB-3.   Works well and I have not seen much UV degradation,
even at Colorado elevations, over the 12 years they have been up.
MUCH cheaper than the commercial stuff.  To date I have only used them
for side-loading.  But with the right setup they could take the top loading
as well.  Just need to cut a disk of SS or aluminum sheet like a big
washer and put it on top.  Then place the weight on back-to-back
muffler clamps so they support the mast and rest on the plate which
sits on the UHMW!    ;-)     (word = milli-picture)

I use a cutting board for my motorcycle stand.  That way I can ride in
and rotate the bike 180 deg and ride back out.   The bearing turns on
the smooth concrete floor pretty well.  But your sheet idea sounds like
a winner to me for some applications I have.

--John  W0UN