[TowerTalk] Lock nuts revisited

[Gary Schafer]

> -----Original Message-----
> From: towertalk-bounces at contesting.com [mailto:towertalk-
> bounces at contesting.com] On Behalf Of Roger (K8RI)
> Sent: Monday, June 23, 2008 2:18 PM
> To: Charles Gallo
> Cc: Tower Talk
> Subject: Re: [TowerTalk] Lock nuts revisited
> 
> Charles Gallo wrote:
> > On 6/22/2008 Roger (K8RI) wrote:
> >
> >
> >> A while back we had a discussion on using lock nuts AKA jam nuts.
> >>
> > ...snip...
> >
> > Probably the definitive book on this stuff is Carol Shelby's book
> >
> > http://www.amazon.com/Fasteners-Plumbing-Handbook-Motorbooks-
> Workshop/dp/0879384069
> >
> 
> Please quote relevant text.  That is permitted under copyright and fair
> use. I really don't want to buy another book as one wall of the living
> room two in the basement and two in here (My den) are full (corner to
> corner) book cases. I never throw books away. I still have all my
> college text books and I graduated in 90. I have to admit I probably
> wouldn't get very far in the advanced math books any more<:-)). I never
> used any of it after a short stint in grad school as a GA.
> 
> Were we just putting two nuts together on a bolt, tightening them
> together, and then turning in the bolt I'd agree that it would be
> nothing more than moving the bolt head down the bolt, but that is not
> what is being done.  The bolt is screwed in the desired depth and then
> the nut is tightened down. This works just like two nuts jammed against
> each other.  The torque required to remove the bolt increases
> dramatically, quite possibly to the point of being unable to remove the
> bolt with out twisting the head off.  You cant physically tighten the
> bolt, or a bolt with the two nuts on it to that torque without doing
> damage.  The main point is  this is easily demonstrated by almost any
> one who cares to try.  HOWEVER, lubricated, cad plated bolts are so
> slippery this is unlikely to work with them at least not until they have
> set for a while. It does work with SS and Galvanized. It works
> particularly well with SS which is what I use for most things.  I don't
> use cad plated bolts as they eventually either become part of what they
> are screwed into, or rust away.
> >
> > --
> > 73 de KG2V
> >
> > For the Children - RKBA!
> >
> > Any given program, when running, needs debugging.
> >  Any debugged program is obsolete.
> >
> Don't forget side effects.
> 
> Roger (K8RI - ARRL Life Member)
> www.rogerhalstead.com
> N833R (World's oldest Debonair)
> 

Roger,

You say that with a lock nut on the bolt that you can not turn the bolt in
the rotator without breaking it.
What you are missing is that with your lock nut on the bolt, it is not the
bolt/rotator that is holding what you are trying to secure but it is the
nut. Either set of threads (bolt/rotator or bolt/locknut) that loosen
release the load.

You could put a stud in and have the same thing. Either the threads in the
rotator/bolt  loosen or the lock nut loosens. Either results in the load
being released. This results in the same as just a bolt with a head being
torqued down.

A double locknut would have the same effect as just a bolt with a head.

73
Gary  K4FMX