Re: [CR] Was Unusual FR Peugeot PX-10, now Wood plug

(Example: Component Manufacturers)

Date: Fri, 23 Apr 2010 20:44:02 -0400
From: "John Betmanis" <johnb@oxford.net>
To: classicrendezvous@bikelist.org
References: <674B61C3DB034BB493732E1E7D2CEFD8@GREER> <4BD1F694.5020205@gmail.com> <91A414D3AC189944BC1F0439710DFAAFC3D883B6CA@EXMBX01.mmeprod.cbeyond> <516930.6670.qm@web84102.mail.mud.yahoo.com>
In-Reply-To: <516930.6670.qm@web84102.mail.mud.yahoo.com>
Subject: Re: [CR] Was Unusual FR Peugeot PX-10, now Wood plug


On 23/04/2010 5:53 PM, Anthony Taylor wrote:
> It is misleading at best to use tensile strength as a comparison in this case. There is no tensile stress involved. Far more likely is bending stress, or fracture toughness. There isn't enough distance from the joint to the bottom of the plug for it to be effective this way anyway.

Being an engineer, here is the jiggery-pokery:

The only stresses are tension, compression and shear. Bending produces tension on one side of the object and compression on the other side.

My theory on the use of hardwood plugs inside the steerer is that this was a simple get-you-home fix if the steerer broke. Most likely, people people started adding the wooden plugs as a safety measure to avoid the pain and injury resulting from a steerer breaking suddenly.

--
John Betmanis
Woodstock, Ontario
Canada