[TowerTalk] K8 Bearing available

Mon Mar 21 20:15:00 EDT 2022

Fafnir, Timken, Torrington all carry the bearings for our tower sheaves.
The part number is the same.   I replaced all the aluminum sheave bearings in three
US Tower HDX  towers.   My HDX589 was done last year.  
The part number is KP8FS464.  I called US Tower to confirm.  
I found them from RBC Bearings off EBAY also.   Check on EBAY, they come up all the time.  Just make sure you use the right part number.  !
Easy to change, press out the old bearing with your bench vise and press in the new one.  Easy Peasy.
In my opinion, its not worth it to try and rejuvenate them.  Just replace them and be happy.

Bob
K6UJ

> On Mar 21, 2022, at 4:26 PM, Raymond Benny <rayn6vr at gmail.com> wrote:
> 
> These bearings have been used by most of the major tower manufacturers over
> the last 40 years or longer. They are the bearings that are pressed into
> the aluminum cable pulley that guides the lifting cables for our amateur
> radio crank up towers. They are not exactly waterproof but do have an
> outside seal that does help keep out the dust.  As mentioned by Grant,
> KZ1W, in many cases, the bearing may be frozen but with soaking in a
> peneratrant, they can be freed up and used again. Personally, I use
> combination paint thinner and automatic transmission fluid (ATF) in an
> ultrasound, vibrating tub that will often clean and free them up. Once
> cleaned, you can hold and rotate the bearing to feel if the bearing is
> internally pitted. If it is, get rid of it!
> 
> As far as I know, Fafnir was one of the original manufacturers and supplied
> them for the German WWII effort. SKF was probably another, but they were
> bombed out of existance during WWII. Later Fafnir expanded to the USA and
> other countries. Timkin and Torrington are some of the more recent
> manufacturers.
> 
> Be aware, the K8 and KP8A are not the same! You want the K8 bearings for
> this use!
> 
> If you have any questions, please ask me or Grant, KZ1W. Grant and I have
> never met, but I have always respected his mechanical experience, as seen
> by his many posts on the TT reflector.
> 
> Ray,
> N6VR/W7YA
> 
> 
> On Mon, Mar 21, 2022 at 3:16 PM Grant Saviers <grants2 at pacbell.net> wrote:
> 
>> Having obtained some from aircaft control cable pulleys marked "Boeing"
>> the ORIGINAL use was just that.  One crank up tower maker actually had
>> pulleys marked Boeing with these bearings rusted solid that I replaced.
>>  With the wider inner race the pulley flanges and cables don't rub on
>> the mounts.
>> 
>> Note the 1998 date on the ebay box.  Fafnir doesn't make these any more
>> AFAIK.  In 1989, I asked them to make an out of production bearing about
>> this size they said, "We can do it since we have the prints. $50,000 for
>> set up and 1000 bearings".  I found away to substitute.
>> 
>> Best to soak these in oil for a while, since the grease is now 34 years
>> old.
>> 
>> Grant KZ1W
>> 
>> On 3/21/2022 14:53, Jon Zaimes, AA1K via TowerTalk wrote:
>>> Found them here:
>> https://www.ebay.com/itm/154716606730?hash=item2405d4110a:g:EbUAAOSwr3VhnbE9
>>> What is their specific use?
>>> 
>>> 73/Jon
>>> Jon P. Zaimes, AA1K Tower climber for hire http://www.aa1k.us/ Cell:
>> 302-632-2353email: jz73 at verizon.net or aa1k at arrl.net
>>> 
>>> -----Original Message-----
>>> From: Raymond Benny <rayn6vr at gmail.com>
>>> To: Tower Talk <TowerTalk at contesting.com>
>>> Sent: Mon, Mar 21, 2022 4:47 pm
>>> Subject: [TowerTalk] Fwd: K8 Bearing available
>>> 
>>> Guess I don't know what I am doing.
>>> 
>>> Go to eBay and do a search on " Torrington Fafnir Aircraft Bearings KP8
>>> FS428 New - FREE shipping" This worked for me.
>>> 
>>> Ray,
>>> N6VR/W7YA
>>> 
>>> 
>>> ---------- Forwarded message ---------
>>> From: Mike Ryan <mryan001 at tampabay.rr.com>
>>> Date: Mon, Mar 21, 2022 at 1:33 PM
>>> Subject: RE: [TowerTalk] K8 Bearing available
>>> To: Raymond Benny <rayn6vr at gmail.com>
>>> 
>>> 
>>> Nothing seen from the link you provided.  Thanks anyway...  - Mike
>>> 
>>> -----Original Message-----
>>> From: TowerTalk [mailto:towertalk-bounces at contesting.com] On Behalf Of
>>> Raymond Benny
>>> Sent: Monday, March 21, 2022 4:14 PM
>>> To: Tower Talk
>>> Subject: [TowerTalk] K8 Bearing available
>>> 
>>> Here is a link to eBay for some K8 bearings. Price is $17.95, shipping
>>> included. The seller says "bearings" so there may be more than one
>>> available.
>>> 
>>> https://mail.google.com/mail/u/0/#inbox/FMfcgzGmvVCwZSvgkmpzJWpMGQKDChQb
>>> 
>>> You can't beat the price anywhere.
>>> 
>>> Ray,
>>> N6VR/W7YA
>>> _______________________________________________
>>> 
>>> 
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