.... Colnago's Steelnovo is the only steel version of this technique that I know of. Internal lugs and welding tubing to it. If you wanted, there is no reason why you couldn't braze the internal lugs.
My next project will be along these lines.
I don't think I've seen the
Steelnovo before. Colnago is certainly not trying to emulate the old style with this frame!
I do like the seat tube decal, as a nod to the heritage.
Steve in Peoria