Those rust holes...

critcritter

Retro Newbie
I would like to ask for advice regarding diagnosing rust damage and options for treating / repairing an otherwise nice and light Univega Alpina 504 frame.
One chain stay, the chain stay bridge and to some extent the bottom of the main triangle are affected (see attached photos). Presumably removing the paint from the affected area should be the first step to diagnose the extent of the under paint rust.

Is this frame safe to ride without chain stay replacement?
Does the bottom of the main triangle look worrisome?
Do you have a suggestion how to check the insides of the tubes without specialized tools (like pipe camera)?
Do you have general suggestions for mitigating the damage?

Thanks a lot!
 

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ooh, I don't like the look of that hole in the stay. I wouldn't ride that because it's a waste of time to build up a frame that clearly has terminal rust issues. Is it safe, short answer, no, not really, we have no idea how big you are, how many potholes you'll hit etc. Long answer, it's unlikely to be a massive issue if it snaps there. It's more the fact that you'd be better off putting energy into a worthwhile project.

As for solutions, it's a steel frame, it can be fixed if you're prepared to spend enough. I'd suggest that some judicious poking with a sharp implement will probably reveal other nasties though and the bill would go up rather than down...
 
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^^Agreed, am afraid to say that the hole proves that rot has taken hold, I'd be poking at that (with a screwdriver) to investigate. Rust can be treated but rot requires repair which is probably not financially viable.
 
Happy to explain! More a term used by owners of 'mature' cars where the rusting is so severe that it has rotted the steel with the only repair possible being to cut out the rot and weld in a piece of new steel. Bikes are not immune and usually caused by storing the bike wet or sweat damage from indoor turbo trainer use. With bikes the repair it would involve tube replacement.
 
Side note- this was an issue with Univega because those parts of the chain stays were the lowest point on the frame- hence water/ moisture gathered there and did it's thang!
 
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