I have this comment about TIG welded frames...
I think the brazed lug is not only a method of joining tubes that can be applied in an artful, expressive manner, but also that the lug offers support to the tube further out from the mitered end. This works as a fillet does, gradually supporting the tube out away from the joint. A fillet offers support by covering a much greater surface area than a butt weld. When I was a kid building model rockets (working, not static models), a fillet built up where the fins attached to the main tube was really important for keeping the fins from breaking off... It seems that a TIG frame lacks that support; the support stops evenly around the weld. I think that the tube's more likely to fail just at that weld edge. Isn't that why lugs have tangs and cut-outs, rather than stopping abruptly like a ring around the tube? Those tangs narrowing and tapering away, offer a little flex while still helping with support.
Am I missing it completely? Are tube sets intended for TIG extra thick at the ends to compensate for there not being external support from a lug?
Sure, I can see some art in welding super-thin tubes together, but is that the best engineered method to build a frame that flexes as a bike frame does?
Cheers,
Duane Kennard Los Angeles, USA
On Nov 10, 2004, at 8:21 AM, gpvb1@comcast.net wrote:
> Date: Wed, 10 Nov 2004 06:26:13 -0500
> From: Tony Rentschler <w.rentschler@mac.com>
> To: classicrendezvous@bikelist.org
> Subject: RE: [CR]measuring ugliness
>
> Suzy Jackson wrote:
>
>> And I agree about TIG. Whilst TIG welds are eminently practical and
>> purposeful, they have no soul.
>
> To which Tony replied:
>
> Learn to TIG weld, and when you can smoothly and cleanly join very
> thin-walled steel tubes with a tiny weld, or, as a challenge, perhaps
> two beer cans or some stainless steel foil, then I just _know_ you will
> gain a new perspective, and see beauty and soul where you now see none.
> "Soul," for my money, is poured into a creation by the builder, and is
> not dependent upon any specific technique.
>
> Tony Rentschler
> New York, NY
>
> Well......
> I'm 99.9% with Suzy on this one, but I'm 0.1% with you if that helps
> any.
> Nothing at all wrong with TIG as a joining method ("some of my best
> friends are TIG...."). There are lots of highly skilled TIG welders
> out there making very nice, functional stuff, but it essentially zaps
> tubes together relatively quickly in order to speed up the building
> process and minimize the QC required. That's why "everyone" does it!
> Cheers,
> Greg "an EF45 man myself" Parker
> Dexter, Michigan