Rust spots under paint, and in fiddly places

[robjh]

My steel framed bike has been developing small rust spots around the fiddly parts around the chain stays, which have largely not broken the surface of the paint - or at least the lacquer layer on the outer surface - but which have gradually joined together to give a 'bubbly' appearance.

I want to treat just these areas, and I'm guessing I'll need to start by somehow filing away the paint and rust. Does anyone have any tips for doing this effectively in such fiddly areas?

Also, any tips for preventing the same thing from happening in future?

I have some Weldtite anti-rust black paint that I was going to use on these areas as I don't see how I would rematch the original paint and don't want to have to redo the whole frame. As long as it's symetrical and in these areas it shouldn't look too bad.

 

[Cycleops]

The problem is you don't know how far the rust has eaten the metal underneath. I can see from the cross piece in the top pic that it looks almost eaten through, you might need to replace it.

I should have the whole frame shot blasted see how it looks and take it from there.

 

[Sharky]

Can't give you any advice on treatment, but is probably a good idea.

I had a steel 531 frame that had paint bubbling near the rear fork ends. Ignored it as it never looked too bad. But out on a ride, it seemed a lot harder than usual and on checking discovered that the wheel was moving considerably from side to side and on further inspection found that the rear stay had broken completely where it had rusted. This one of the few occasions that I phoned the OH to come and collect me.

 

[Gravity Aided]

Quite the problem, especially with the drain or bolt holes in the cross members, as there may be rust from the inside out. I usually use the same method as @User9609 does for this, but I use a household cleaning vinegar at a higher concentration, and a metal etching primer with epoxy spray paint for the finish.

 

[Illaveago]

You could try using Hammerite Rust Removing Gel. Brush it on and work at it with an old toothbrush brush. You may have to apply it several times but it is amazing how things turn out . Once it has cleaned up the affected areas you will get a better idea of how to proceed next .

 

[Illaveago]

Here are some pictures of the effect it had on a rusty bike frame . I applied the gel and worked at it with a tooth brush and then applied some more a bit later. I washed it off with water and this is the result .

 

[screenman]

A bit off dry 600 would have done that faster and with less mess. 240 grit would have made a lovely job ready for priming.

 

[Illaveago]

A bit off dry 600 would have done that faster and with less mess. 240 grit would have made a lovely job ready for priming.

I'm afraid not ! I've used it on many rusty components which I thought were beyond restoation and have been surprised how well they came out .