Today all of the welding was completed, as I added the seatstay bridge and all of the brazeons.
First rear wheel spacing was again checked. Welding the seatstays brought the axle spacing to 127 mm. However, the seat stay bridge still needed to be welded on, so an axle of 137 mm was installed, bridge was mitered, and breather holes were drilled in the seatstays and bridge. Because I'm building a cross bike and not a road bike, I did not have to worry about the bridge being the exact dimensions for dual pivot road calipers. I gave myself plenty of clearance for a 35 mm wheel + extra mud clearance.
It would have actually been really nice to scotch-brite and acetone the entire frame after this step, as this is the "purest" the frame would ever look. If I was building a fixed gear bike with no brakes, I could have done this, but the reality is geared bikes that need brakes need all sorts of Braze- ons to host the various cables that make the bike shift and stop.
Holes were drilled for water bottle cages. You typically want to only add what you absolutely need, and while you'll never run water bottle cages on a cross course, I wanted the option of having two bottles for riding singletrack, or when I decide to take my cross bike on road rides.
Brazeons were then added and were welded to frame. All of the brazeons came with a little lip around them, which served as a filler material and made welding alot easier. Clamps were used to hold brazeons in place for tacking and welding.
Brazeon clamp for single cable stop:
Clamp on for downtube shifter cables:
My brazeons would be somewhat different than Jim's road bike. I would be routing my derailleur cables along the top of the bike, which would then require running single cable bosses down the seat tube (for the front derailleur) and 2 single cable bosses down the back of the seat tube:
I would start out with a fixture to attach my cantilever brakes.
Welded bosses:
Rear of frame with cantilever brake boss welded on:
Finished bike! (...sorta)
Tomorrow, final prep on the bike will be done, and frame will be checked for alignment.
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