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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