Jan Heine asks:
>Does it really make for a stronger joint?
Unfortunately, no. I like the style aesthetically and have done some frames that way, but the tubes need to be just a little on the thick side compared to a silver-brazed lug joint.
Any frame joining method, if done correctly, makes a joint that's stronger than the tube just adjacent to the joint. Thus the strength of the joint is irrelevant. All that matters is: what effect does the joining method have on the strength of the tube.
One of the most important factors there is the amount of time the joint was hot - getting the joint done quickly is better. So any extra time spent filleting the lug after the lug is brazed weakens the frame. That it makes the lug stronger is irrelevant because the unfilleted lug would not have broken.
Yes we've all seen frames that cracked within the lug itself, but I'm only talking about properly-brazed frames. A framebuilder who hasn't mastered the basics of mitering and brazing, or is too rushed to take the requisite care, is unlikely to use this technique anyway.
Mark Bulgier
Seattle, Wa
USA