Re: [CR]Race car brazing, silver etc.

(Example: Framebuilding:Tubing:Falck)

Date: Wed, 12 Mar 2003 23:11:52 -0500
From: "Joe Bender-Zanoni" <joebz@optonline.net>
Subject: Re: [CR]Race car brazing, silver etc.
To: Philcycles@aol.com, classicrendezvous@bikelist.org
References: <3d.2d2017fb.2ba1499e@aol.com>


Jim Redcay built race car chassis before he built bicycles. I bought my first frame from him when he showed me cutaway test samples showing the braze penetration and internal fillets of his silver brazing. Of course the $125 price and 10 day delivery on my custom frame was a factor.

How many builders have done cutaways to establish their braze integrity? Anyone seen or know of other examples?

As to 60's and I presume 70s Paramounts their "overstuft" approach is really something. Per Dale's comment the bridges and dropouts have big fillets and have to be a different brazing alloy than the lugs. Not to say the lugs aren't flush with braze material either. Dave S., do you know? No Paramount was ever gonna fail for lack of brazing material seems to be the motto.

As I have said before, probably too many times, I designed a lugged, silver brazed cro-moly driveshaft for the ammunition magazine on the F-15 Eagle aircraft. The braze gap is tightly controlled by way of tolerences and fixtures, machined silver braze material inserts are put into the fixtured parts and the whole shebang is heated in an oven in a controlled temperature cycle. Unlike a bike tube, this is a torque shaft and as Harvey said, silver is good in shear and ideal for this application. Just as an aside, double butted tubing in such a shaft would be an error because 1) the torque is constant throughout the tube and 2) the tube mechanical properties are constant because the heating cycle etc. was in the oven applied to the entire tube andresults in the same machanical properties throughout the tube after brazing.

Joe Bender-Zanoni
Great Notch, NJ


----- Original Message -----
From: Philcycles@aol.com
To: classicrendezvous@bikelist.org
Sent: Wednesday, March 12, 2003 9:40 PM
Subject: Re: [CR] Now "Bronze welding"



>
> In a message dated 3/12/03 2:06:17 PM, OROBOYZ@aol.com writes:
>
> >Hmmm. I think the British were talking about filet brazing when saying
> >
> >"Bronze Welding" for instance as did the Taylor Bros. in their tandem
> >making.. Ain't no melting of parent metal there.
> >Maybe just a misapplication of the phrase?
> >I hadn't ever heard of the term "Bronze Welding" being applied to oxy-acet.
> >
> >welding..
>
> Absolutly correct. When the english say bronze welding they mean brazing.
> this is the method all the great British racing cars used, as well.
> Phil Brown
> Still no cute name for San Rafael but give me time