----- Original Message -----
From: "jeremy-ca" <km1h@jeremy.mv.com>
To: "Ian White GM3SEK" <gm3sek@ifwtech.co.uk>; <towertalk@contesting.com>
Sent: Sunday, 26 August, 2007 5:40 PM
Subject: Re: [TowerTalk] Fw: Rohn 45 Question
>
> ----- Original Message -----
> From: "Ian White GM3SEK" <gm3sek@ifwtech.co.uk>
> To: <towertalk@contesting.com>
> Sent: Sunday, August 26, 2007 4:12 PM
> Subject: Re: [TowerTalk] Fw: Rohn 45 Question
>
>
>> Mark Robinson wrote:
>>>From: "Blake M" <n4gi@tampabay.rr.com>
>>>To: <towertalk@contesting.com>
>>>Sent: Sunday, 26 August, 2007 1:35 PM
>>>Subject: Re: [TowerTalk] Fw: Rohn 45 Question
>>>
>>>
>>>> The bottom bolts on a Ham IV I had would work loose every few months
>>>> when
>>>> I
>>>> had no load on it (I bought into the thrustbearing-takes-the-weight
>>>> thing
>>>> when I was new...). After I placed the full load of antennas and mast
>>>> on
>>>> it, this problem stopped.
>>>>
>>>> Rotors have HUNDREDS of bearings in them. Most thrust bearings I've
>>>> seen
>>>> only have 10-20.... I'm no expert in physics, but where to put all the
>>>> weight seems like an easy decision to me.
>>
>>>Maybe a flat washer and a spring washer would stop the bottom bolts
>>>coming loose. Blue loctite will certainly stop them coming loose.
>>>
>> Blue Loctite is excellent for many antenna jobs. It lubricates as you
>> tighten the threads (prevents galling of stainless steel), locks the
>> threads together so they won't vibrate loose, and seals them against
>> corrosion... yet you can still unscrew the fastenings for maintenance.
>> Clever stuff.
>>
>> However, threadlock is only a special type of glue, so it won't work if
>> the threads in the rotor casting are loose or corroded. The answer then
>> is to re-thread the holes to a larger size, and use *red* Loctite (the
>> permanent locking grade) to fix lengths of stainless steel studding into
>> the casting. The two parts of the rotor can then be held together by
>> nyloc nuts, on the underside where they're easy to work on.
>>
>> 73 from Ian GM3SEK
>> http://www.ifwtech.co.uk/g3sek
> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> When there is insufficient meat to drill oversize, even to a metric size,
> then JB Weld or a similar hard epoxy can be used to fill the hole. Then
> drill and tap to the original size. Ive done this with success to the base
> of the RC5A-3 as well to the top bell of several HAM-M size rotators.
>
> Carl
> KM1H
> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Have you ever tried to helicoil it instead?
Mark N1UK G3ZZM
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