Re: [CR]testing brazing

(Example: Framebuilders:Dario Pegoretti)

Date: Thu, 13 Mar 2003 12:21:10 -0600
Subject: Re: [CR]testing brazing
From: "Todd Kuzma" <tullio@TheRamp.net>
To: <MSCTROSE@aol.com>, <goodrichbikes@netzero.net>, <classicrendezvous@bikelist.org>
In-Reply-To: <46.368784f9.2ba22050@aol.com>


on 3/13/03 11:56 AM, MSCTROSE@aol.com at MSCTROSE@aol.com wrote:
>
> In a message dated 3/13/03 9:24:25 AM, goodrichbikes@netzero.net writes:
>
>
>> I've also had my brazing tested by several independent testing facilities. 
>> Joe Starck and I built many forks for Rivendell for testing of a new fork
>> crown.  It was quite interesting.
>>
>
> Curt
> Please tell us the testing procedure. Inquiring minds want to know. Is
> this procedure done for >gasp< modern, off topic, factory made forks as well?

There are DIN and ISO standards for dynamic fork fatigue. The fork is mounted in a test fixture. The steerer is held in a fixed position with a full headset. A loading attachment is clamped in the dropouts. The ISO test requires a load of 99 lbf to be applied for at least 50,000 cycles at a maxmimum frequency of 25 Hz. The DIN test requires a load of 68 lbf to be applied for at least 100,000 cycles. For reference, the Heron fork was tested by Specialized with a load of 99 lbf over 250,000 cycles without failure.

Todd Kuzma
Heron Bicycles
LaSalle, IL 815-223-1776
http://www.heronbicycles.com