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Re: [TowerTalk] Seized mast clamp bolts Hy-gain 10 meter yagi

To: Ian White GM3SEK <gm3sek@ifwtech.co.uk>
Subject: Re: [TowerTalk] Seized mast clamp bolts Hy-gain 10 meter yagi
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
Date: Mon, 04 Jan 2010 03:55:03 -0500
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>

Ian White GM3SEK wrote:
> Mike Besemer (WM4B) wrote:
>   
>> >From http://www.estainlesssteel.com/gallingofstainless.html...
>>
>>
>> "Thread galling seems to be the most prevalent with fasteners made of 
>> stainless steel, aluminum, titanium, and other alloys which 
>> self-generate an oxide surface film for corrosion protection. During 
>> fastener tightening, as pressure builds between the contacting and 
>> sliding thread surfaces, protective oxides are broken, possibly wiped 
>> off, and interface metal high points shear or lock together. This 
>> cumulative clogging-shearing-locking action causes increasing adhesion. 
>> In the extreme, galling leads to seizing - the actual freezing together 
>> threads. If tightening is continued, the fastener can be twisted off or 
>> its threads ripped out."
>>
>> I always use an anti-seize compound on stainless hardware.
>>
>>     
>
> I've never felt comfortable about using oil- or grease-based materials 
> on threads that are supposed to stay tight afterwards.
>
> A lesser-known feature of Loctite and similar thread locking fluids is 
> that they also prevent galling when the nuts are being tightened. I've 
> always had good success with the "blue" Loctite grades like 242 which 
> are designed to be released with hand tools. SS nuts tighten up smoothly 
> and the galling doesn't happen.
>
>   
I believe you will find that even the so called permanent Loctite, will 
cleanly release with a bit of heat.

However if the proper torque is achieved with neverseize the nuts will 
not come loose. OTOH a nut installed to 100' lbs with never seize on the 
threads exerts *far* more pressure on the bolt than does one torqued 
down the the same numbers dry.

73

Roger (K8RI)
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