Date: Wed, 22 Oct 2003 15:02:11 -0700
Reply-To: Jeffrey Schwaia <jeff@TSSGI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Jeffrey Schwaia <jeff@TSSGI.COM>
Subject: Re: SHEAR bolts/steering column
In-Reply-To: <5.1.0.14.2.20031022154110.05e15748@pop1.attglobal.net>
Content-Type: text/plain; charset="us-ascii"
Good point. Perhaps we have a semantics issue here.
Besides, if the purpose of these bolts was just to allow them to shear upon
impact, then why would the heads shear off during installation? Do you
"shear bolters" out there really believe it's to stop them from being
over-torqued? Come on, with all the items on a Vanagon that need to be
torqued during assembly, this is the only item that has idiot-proofing? Get
real. I did a little snooping on the net as well, and there are many
references to shear-headed bolts as anti theft devices.
If my memory serves me correctly, I've seen them used on motorcycles as
well. Perhaps to help prevent components from being removed? Hmmmm....
Additionally, if VW created these bolts only for the shear-off factor, why
wouldn't they put a hex head under the sheared off head for maintenance
purposes? Hmmmm....
I think it's probably safe to say that the bolts serve two purposes,
security and safety.
Just my humble opinion.
Cheers,
Jeff
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf
Of David Beierl
Sent: Wednesday, October 22, 2003 12:47 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: SHEAR bolts/steering column
At 02:35 AM 10/22/2003, George Goff wrote:
>On this list, the subject of those damn shear head fasteners is a bunch of
>speculation which reappears according to some kind of hidden schedule. I
have
>yet to see any statement from VW engineering regarding the matter, so the
>debate and speculation continues. I tend to favor David B.'s opinion that
the
>bracketry supporting the steering column is just too deformable to support
>shearing those fasteners regardless of their composition. While I can
>respect an
A cursory "search of the literature" i.e. google shows that there are many
references to shear bolts which are clearly designed to shear under impact;
but that references to bolts in the vicinity of ignition locks/steering
locks on autos and motorcycles often refer to "shear-head" bolts and never
make reference to any further shearing once the bolt is installed. At
least two references call them out specifically as anti-tamper and/or
anti-theft devices.
cheers,
david
--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"