Columbus Air Repair Work - to pull apart or not to pull apart

Gidday all,

I recently got my hands on a super nice CHCH built track frame with Columbus Air tubing, it’s a super nice frame and has been ridden gently for the past 30 years, however, the picky standards I hold for bikes I own doesn’t give it a pass… There are small details like the fact the silver braze work is fairly rough, for starters there are areas where the silver has been burnt out around the seat tube lug, the stay ends aren’t even, and there’s been a dodgy repair to the seat stays so they don’t sit parallel when viewed side on to name a few.

My first plan of attack is to pull the frame back, tidy up the mitres (they haven’t been deburred and show filing marks), tidy out the silver from the lugs, and braze it all back together with nickel bronze. My question going down this route would be in the strength of the tubes, having had one heat cycle already when assembled I’m worried about stuffing the tubes with a second heat cycle and then risking having it break on me catastrophically; seeing how the majority of it was silver brazed it wouldn’t have too much heat put into it so it’s only running half a heat cycle so I thought I could pretty safely pull it apart and rebuild with the same tubing to my standards and get it the way I want.

My second plan of attack was to get the frame sandblasted back to remove any paint, clean up the whole frame and the silver braze the joints to get as much silver into the voids of the lugs as I could and then carefully sharpen up the lug shorelines with a file again. My worry with this plan is that there are 30 years of contamination inside the botched joint which isn’t be easy to remove, I’m also not happy with some of the lugwork but I can fix that with a thin spread of silver and then dressing down so it’s even.

What’s everyone’s thoughts here, should I pull the frame apart to its individual tubes and then rebuild it to my standards or should I give it a quick fix with silver and cover it up with paint? In both fixes, I plan to correct the lugs and stay ends by adding a radius to the dropout slot and then fixing all the misaligned lug shorelines so the only difference is my quality and standards that will go into ensuring it is perfect.

I will update this thread tomorrow with some pictures of the debauchery.

2 Likes

It gives me a bit of pause for someone asking these questions to suggest they can disassemble and re-assemble without causing damage AND end up with better results than the original (presumably done by a professional). Are you that confident in your brazing and finishing skills?

I generally start with the least invasive option and go from there. I certainly wouldn’t disassemble it to re-assemble it. Each deficiency will likely require a different solution. Old bikes can be fairly crude by modern custom bike standards.

Do you know what the filler is in the lugs? If it’s silver, you may be able to strip it and fill in around the shorelines. I would use silver, not nickel?

1 Like