Towertalk
[Top] [All Lists]

Re: [TowerTalk] Thrust Bearing for Use with Prop Pitch Rotor

To: "Steve, NR4M" <steve@nr4m.com>
Subject: Re: [TowerTalk] Thrust Bearing for Use with Prop Pitch Rotor
From: Jim <jimw7ry@gmail.com>
Date: Mon, 11 Mar 2019 19:04:22 -0500
List-post: <mailto:towertalk@contesting.com>
Steve...

I had no issue with my 2" chrome molly mast. But the gallivanting is not very heavy on it. Now its up with a short 2" OD aluminum mast. Fit fine.

When I first up it up in 1990, I used 2" schedule 80 black pipe. Which is not 2" od. More like 1-7/8 OD.

As Stan suggested, use a 2-1/8" bearing if your worried about it.

I would suggest using hex head "set" screws. Rather than the Allen head ones they ship with.


Thanks
73
Jim W7RY

On 3/11/2019 7:33 AM, Steve, NR4M wrote:
Jim,

How is the fit on the ID?

So, many of this type of bearing will not work due to the tight tolerances. A mast 
that’s been galvanized usually will not fit.

73 de Steve, NR4M

Sent from my iPhone

On Mar 11, 2019, at 8:23 AM, Jim <jimw7ry@gmail.com> wrote:

This is what I have used for 30 years. Same bearing on 4 different towers in various 
locations. In Southwest Washington, we got 70" of rain per year. Held up fine.


https://www.ebay.com/itm/UCF211-32-2-Square-4-Bolt-Flange-Bearing/362153741170?hash=item54520b8b72:g:a2QAAOSwnTdaA6IQ


I do put a cover over the top of it with a vent pipe roof jack (just the rubber 
part) to keep water out.


Thanks
73
Jim W7RY

On 3/10/2019 10:32 PM, Tim Duffy wrote:
Best bearing - can take lots of weight.

https://www.dxengineering.com/parts/dxe-tb-300

Very different from the Rohn

73
Tim K3LR

-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
Patrick
Sent: Sunday, March 10, 2019 12:20 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Thrust Bearing for Use with Prop Pitch Rotor

I'd double check the need for a down thrust bearing to relieve the
weight from the PP unit. Kurt Andress the preeminent PP re-purpose guru
advised me against it.

Patrick        NJ5G


On 3/10/2019 10:16 AM, Mike wrote:
Hello,

What have others used to take the weight off of a tower mounted prop pitch
rotor?

Presently, in the final stage of modifying a rescued prop pitch and,
unfortunately,  it didn't have the triangle bearing plate.  Plan to use a
couple of Rohn TB3 thrust bearings, one at top of the tower and the other
approx. 2 ft below the top, but wanted to find out what others
successfully
have used to keep the weight off prop pitch rotors.

The load will consist of a 2" dia. X 1/4" wall X 21 ft chrome molly mast
plus a homemade 40 m Moxon (approx. 70 lbs) and a 4 el SteppIR (approx. 50
lbs).

I've review the TT archive for thrust bearings for possible application
with a prop pitch rotor without any consensus on what to use other than
the
available thrust bearings are not reliable in the long run.

    73,
    Mike, K4GMH
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

---
This email has been checked for viruses by AVG.
https://www.avg.com


_______________________________________________



_______________________________________________
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

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
<Prev in Thread] Current Thread [Next in Thread>