The Amateur Block was actually Phenolic. I would not use wood, as wood absorbs
moisture and swells. That might put the "squeeze" on the mast and bind the
rotor.
An idea: Go to WallyWorld and get a plastic cutting board as thick as you can
find. Cut it into pieces that will fit the top plate of the tower. Bolt the
pieces together with flat head bolts so the heads will not interfere with the
top plate, while the nuts will stick up in the air bothering nothing. Drill the
mounting and mast holes and use it. The plastic will not retain moisture and
will provide a smooth inner surface against which the mast can turn. The only
"yahbut!" to the whole procedure is that the plastic may degrade in the sun.
Just an idea..
Clint - W5CPT
----- Original Message -----
From: ersmar@verizon.net
To: Rob Frohne ; towertalk@contesting.com
Sent: Wednesday, March 21, 2007 11:35 AM
Subject: Re: [TowerTalk] Inexpensive thrust bearing?
Rob:
Use a block of wood. My Rohn catalog from ca 1987 carried a thing they
called an Amateur Block (P/N AB) that was intended to be bolted onto a flat top
plate. It was nothing more than a block of wood with an appropriate hole for a
mast drilled through it. IIRC it might have even been split through the
diameter of the hole to allow for some slop in its fit around the mast.
73 de
Gene Smar AD3F
From: Rob Frohne <frohro@wwc.edu>
Date: 2007/03/21 Wed PM 12:06:59 CDT
To: towertalk@contesting.com
Subject: [TowerTalk] Inexpensive thrust bearing?
Hi Everyone,
Does anyone have a source for an inexpensive thrust bearing? I have a
plate on the top of my tower with a hole through it, and was thinking of
putting a thrust bearing on, but the ones I found were around $50 which
for my frugal self is a bit spendy for a thrust bearing. It seems that
there is probably a cheaper way to do this with some kind of automobile
bearing or a sleeve of pipe and some set screws, etc. Does anyone have
any advice?
73,
Rob, KL7NA
--
Rob Frohne, Ph.D., P.E.
E.F. Cross School of Engineering
Walla Walla College
100 SW 4th Street
College Place, WA 99324
(509) 527-2075
http://www.wwc.edu/~frohro/
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|