[NSRCA-discussion] Broken Hyde mount beams (my fault)

[jivey61 at bellsouth.net]

Lance
 This is the same responce I get from Merle when I have had problems.Usually
something I cause to happen. What a great person to deal with.

Jim Ivey
----- Original Message ----- 
From: "Lance Van Nostrand" <patterndude at tx.rr.com>
To: "hydesoftmounts" <hydesoftmounts at mymailstation.com>; "NSRCA Mailing
List" <nsrca-discussion at lists.nsrca.org>
Sent: Monday, April 23, 2007 8:56 PM
Subject: [NSRCA-discussion] Broken Hyde mount beams (my fault)


> [pattern guys, hope you find this interesting/helpful.  I had an aluminum
> beam break on my CR mount. The mount had about 1000 flights.  I sent it to
> Hyde Mounts for analysis, not knowing if he'd really be interested.  Merle
> responded right away with this. --Lance]
>
> Merle,
> I will gladly pass this on.  I'm glad you got to looking at it.  It was
not
> obvious why it would break at that location.  I thought those impressions
> were due to over tightness.  I never noticed the screws being loose, but
it
> makes more sense that the impressions were made by a loose engine than a
> tight one.  this has now become a much more interesting problem.  Your
> recommendation to check and retighten as part of periodic maintenance is a
> good suggestion and this experience proves it.
>
> It is always great to work with you.  Some businessmen wouldn't want this
> information distributed, so your commitment to making the best product
> possible and your openness should be shared along with this information.
>
> --Lance
>
> ----- Original Message ----- 
> From: "hydesoftmounts" <hydesoftmounts at mymailstation.com>
> To: <patterndude at comcast.net>
> Sent: Sunday, April 22, 2007 6:38 PM
> Subject: Beams
>
>
> > Hi Lance,
> >
> > Its been a windy weekend here - for sure!
> >
> > I now know why the beam broke.  Over the years I have only had a few
> > aluminum beams break that were not crashed or impacted.  I have saved
the
> > broken beams and never fully understood or conducted an analysis as to
why
> > they had broken for only a few and not others.  After receiving your
> > broken beam I studied the other few I have saved.  In each case the
broken
> > beam had a wear impression on it that was located exactly where the rear
> > of the engine lug caused such impression/depression by being permitted
to
> > operate with the screw(s) being slightly loose.   The wear impression
> > obviously causes "work hardening" of the aluminum and the breaks have
> > always been at the used tapped hole or with some beams at the location
of
> > the unused tapped hole located directly under the position where the
rear
> > of the engine lug contacts the beam.  The beam breakage does not occur
at
> > the position of the lightening holes which removed considerably more
beam
> > material - breakage
> > at the position of the lightening hole would be most obvious - but this
is
> > not the case.  "Work hardening" is the only reasonable conclusion.
> >
> > Even nylon composite beams, that have not been crashed or impacted, and
> > that have been properly drilled/prepared, can also break at the position
> > of the "wear impression" that is created if permitted to operate with
the
> > screws loose.
> >
> > Over the years I occasionally ran an ad in the K-Factor that advised
Hyde
> > Mount users to check the tightness of fasteners/screws.  Another problem
> > some have had is that the mount may loosen on the firewall.  In all
cases
> > the loosening was caused by insufficient tightening and also over time
the
> > blind nuts compressed the firewall and permitted the mounts to get loose
> > on the firewall.  The key to preventing this is to tighten screws very
> > tight and also ensure "hard points" at all bolting locations.
> >
> > My suggestion is to ensure tightness of fasteners - and use a "T" handle
> > type allen wrench and not be timid when tightening - securing screws
VERY
> > tightly, to torque specs, will not damage any part of a Hyde Mount!!!
> >
> > I am not on the internet, nor do I have access to the NSRCA "chat room"
> > site.  I would appreciate it if you would pass this information along -
> > others may benefit.
> >
> > Thanks,
> >
> > Merle
>
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