]I picked up a old steel road bike a few weeks ago as a project and I think the seat/chainstays are out of alignment. It was impossible to get the rear brake to work because with the rear wheel aligned in the chainstays the rim was about 4mm out at the brake bridge. It didn't help that the wheel had a broken spoke and the dish was out so I tried Sheldon's string method.
It was about 2mm out on one side at the seat tube according to this (obviously the sheldon method assume the rest of the frame is straight!
I also tried flipping it around to rule out the dish of the wheel being the issue as well as using another correctly dished wheel. The alignment is better with the wheel flipped and with the other wheel, but the rear triangle is definitely out of alignment.
It's hard to illustrate but here's a photo of the bike - is it worth fixing/spending money on? Or should I just sell the components?

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