I realize this is an old thread but this response may help someone: Several years ago Craig Brown of Brown's Welding, 2754 N. 47th Street, Boulder, CO 80301; 303-442-3946, did some welding on parts of the 1942 Columbia U.S. Army bicycle which I was restoring. His work was pricey but amazing! I recall that he had a couple of serious sport bikes in his shop at that time. Brown's Welding is on the south side of a long light industrial building just southwest of 47th St. and Sterling Dr. just east of Foothills Parkway.