Originally Posted by
noglider
I'm really kidding about the head angle. I doubt it's a significant difference, if any.
I'll measure as soon as I get it built up. I have another Gran(d) Sport(s) to compare to, I didn't measure this one prior to torch work as I didn't see a need to change the geometry.
Originally Posted by
SJX426
Many have expressed my thoughts so I won't repeat. I am curious about where the seam is on the HT.
Why?
Wondering if the seam was faulty and gave way. Though I would expect a split instead of a bulge. But then again, if it was a penetration issue, maybe part of the seam held to support a bulge deformation.
The seam is on the "back side" where the bulge is. It may be coincidental. Outside of deflection where it's bulged, I didn't see anything out of the ordinary, like a cracked seam, rust, etc. I could take a hacksaw, cut up the head tube, make x-sections, polish, and have it sent out for analysis, check the grain structure and phase, do hardness testing, etc. But why? I'd just be giving a defunct manufacturing process some QC information to feed back to their non-existant production line. Ghosts in the machine, one might say in an imperfect analogy.
The techniques used today by most modern framebuilders with modern equipment are a big improvement from those used "back in the day". Most builders use silver filler for lugs now, so tubes just don't get heated up that hot. The couple of bucks savings from using a seamed, carbon steel tube for a head tube don't make sense anymore when even the least expensive production lugged frames start around a grand or so.
As is often said, we stand on the shoulders of giants.