Re: Defense of PDQSHIP and Phil Payne...

[BJohn77777@aol.com]

In a message dated 96-10-04 11:13:08 EDT, "Fellow Washingtonian at heart" Al
Powell writes:

<< SO - what harm is it likely to do to OVER-tighten the lugs by perhaps 
 10-15 lbs/ft (at the outside) by adding anti-sieze?  I submit that 
 this error is **trivial**!  

Actually Al, the difference can be as large as 25% on plated (chrome,
cadmium, etc.) fasteners, even greater for those lubed with the "abused" AS.
 Engineers spend much time breaking things to determine the safe
operation/use of the product.  There are more forces involved besides the
immediately Thank the Audi gods for over engineering of Audi's wheel holding
devices.  Just don't try this on a urabuS or many others in the econo-box
class, or you WILL have major problems.  (Experience observations from the
wheel and tire installation business)  Heck, even the major tire installation
guides, factory repair manuals, bolt manufacturers et al  strongly advise
(under the heading of WARNING) against such a practice.

<<I am not likely to cause any rotor warpage because they will all be
tightened to the same (possibly, not certainly)
 slightly excessive torque; the lug bolts will not be stressed sufficiently
to cause them to stretch and fail; 

However, the reallynicesuperfancysparklyexpensivealloy wheels bolt seats are
that much closer to stress fracturing.  The lug bolts are prolly not gonna go
south immediately, but will have their useful lifespan substantially
shortened.  The major area of concern would be the threads themselves.  They
are the ones that will distort and fail long before the body of the bolt due
to "minor" overtorquing.  Excess thread distortion is one of the major causes
of siezed lug nuts/bolts, and anti-sieze just masks the pending doom.
 (Substantial experience in the aviation world)  I could go deep into the
theories of torque (rotational) and tension (stretch) effects, as well as
could Scott,  I don't think anybody has a spool long enough for the potential
thread. :^) 

<<my experience tells me they will not loosen, and they will therefore not
fall off.   All the criteria for 
 performance I listed are met.  What's more, I know that the lugs 
 will not lock up.  I have no such assurance that cleaning the threads 
 will asure this - they are still subject to weather and heat.  I 
 grant you that cleaning the threads may be a neat idea, but I doubt 
 that the other priorities on my time will ever incline me to do so.

An excerpt from Barnhill Bolt home page:
"We suggest that in order to acheive adequate tightening and safe results
that personnel using the torque control
technique should be carefully trained in the theory and methods of
tightening. Bolts that have been overloaded too far beyond their proof load,
or if threads have been seriously distorted during tightening, should be
replaced."

Have a fastener question"mailto:ross@barnbolt.com"

 
<< Saunders' Slant: "If it's worth doing, it's worth hiring someone
<<  who knows how to do it."
<<  >>

Gee,  I kinda like that ditty...  ;^)

Watch the blinking cursor and repeat after
me...cleananddrycleananddrycleananddry...

Bruce Johnson
85 4Ksq
Olympia, WA