Removing and protecting against rust

[CDollarsign]

I found some rust on my corsa extra today. First spot is in the 'EM' logo on the fork crown, second on the underside of my tt a the st intersection. What can I do to remove the rust and prevent it from coming back. One location is chrome and the other is painted if that matters.

[Cicli]

I have used this product. Works very well and Eastwood products are top notch.

http://www.eastwood.com/eastwood-rust-converter.html

[11.4]

Rust can come about from at least four sources:

1. Weather, though this is usually internal in tubes and lower down on the bike because that's where the water drains and gets trapped.
2. Sweat, which is probably a contributor here since perspiration while riding can collect on the underside of the top tube and on the top of the fork crown.
3. Painting failures, which might be a case in either instance here because bike framer painters, particularly European production frame painters, often did atrocious jobs.
4. Flux left on the metal and painted over, which caused corrosion to start under the paint. This could be a case in either situation here because both are fluxed areas and again, European production frames were rather susceptible to this problem. A related problem is that European chrome can be like European paint and be very rust prone.

You can address sweat-induced rust by washing the bike off well after rides. A soft brush, a small bowl of warm water with a little cleaning solution in it (bike cleaning solutions from any of the leading manufacturers), and toweling everything dry afterwards will help here. You can't do much about painting or flux problems except to be careful about sweat.

Chrome is applied with an electrical charge, and some shapes on a bike frame can prevent the chrome from applying evenly. Cutouts on a fork crown are such a case, and I'd never trust chrome in cutouts, around sharp corners, and so on. I'd paint a little rust converter or simply some rust-converting primer inside the cutouts on the fork crown and then apply a high quality paint in a color inside the cutouts to match a color on the frame. It looks cool and your fork will have a lot more protection than just the chrome it's been depending on so far.

As for the top tube problem, you may have weak paint there or possibly there was a frame pump or something that either rubbed paint or trapped sweat in that spot. I'd use rust converter or a rust-converting primer. (I prefer the primers because they keep a protective coat in place; converters alone are used to remove rust on bare metal and don't give physical protection beyond the conversion chemistry itself.)

Some people will touch up rust or scratches with clear fingernail polish or Testors model paints. I've found that both have been reformulated over the years and what one can get today are made for easy application but not with durability in mind (nails get stripped and refinished fairly frequently, and model paints don't have to be durable). When I've used them on frames, they fade, abrade easily, and don't offer all that much protection where it counts. Auto paint touch-up pens work better and are made to do what we want in a bike frame paint, and are cheap on Amazon. You get both a base color and a clear coat, and it's worth it to read the instructions and follow the process. They still aren't as good as a small sample of actual frame paint from the painter, but do the job.

[AngryScientist]

the new style duplicolor touch up paint kits look like below and have everything you need and come in a slew of colors to get you close.

the top of the cap has an abrasive chisel tip section which you use to remove the surface rust and roughen up the area to be touched up. the base coat is then applied and the bottom "well" section of the stick contains clear coat. read the instructions and go for it.

http://duplicolor.com/assets/img/product-detail/allin1.png

[11.4]

the new style duplicolor touch up paint kits look like below and have everything you need and come in a slew of colors to get you close.

the top of the cap has an abrasive chisel tip section which you use to remove the surface rust and roughen up the area to be touched up. the base coat is then applied and the bottom "well" section of the stick contains clear coat. read the instructions and go for it.

http://duplicolor.com/assets/img/product-detail/allin1.png

Yes. These are the ones I was referring to. There are a couple other brands if you need to sort around to get the right color. I didn't think that chisel tip was to serve as an abrasive. On the ones I have it's like a felt-tip pen for the paint, and you can unscrew it and find a tiny brush if you need that. The felt-tip regulates paint application a bit better than the brush and gives you a very thin coat so you can do several coats and match the neighboring paint surfaces.

[AngryScientist]

Yes. These are the ones I was referring to. There are a couple other brands if you need to sort around to get the right color. I didn't think that chisel tip was to serve as an abrasive. On the ones I have it's like a felt-tip pen for the paint, and you can unscrew it and find a tiny brush if you need that. The felt-tip regulates paint application a bit better than the brush and gives you a very thin coat so you can do several coats and match the neighboring paint surfaces.

the new ones are a 4-in-one.

chisel abrasive tip
pen tip for main color
brush applicator for main color
brush applicator for clear coat.

[tylercheung]

would rust converters work in conjunction with, or in replacement of Framesaver for tubing interior?

[old_fat_and_slow]

1.) Remove surface rust with wire brush or steel wool.

2.) Follow-up with this:

https://www.theruststore.com/Bull-Frog-Rust-Remover-P22.aspx

3.) Paint as needed.


Rust is a cancer, if you just remove surface rust and paint, the rust will eventually come back. Step 2 is critical.

[Kontact]

Before using an abrasive or converter, try removing the rust with oxalic acid, the active ingredient in Barkeeper's friend:

https://rainonatinroof.com/how-to-remove-rust/


Abrasives also remove paint and chrome, and converters don't remove rust but stabilize it into a different substance. Oxalic acid just dissolves it while leaving everything else alone.

[CDollarsign]

I wish I had known that! Those pens angry scientist recommended worked out pretty well and I seem to have gotten it all. I have tons of barkeepers friend because i use it to clean my allclad pans. Will try next time (hopefully there isnt).

[speedevil]

Evaporust works very well to remove rust. For tubes, you can soak a folded paper towel in evaporust and wrap it around the tube. Then use kitchen cling film to hold it in place. The same technique should work on fork crowns as well. It doesn't damage paint or decals (as long as they're under clear coat) and has been effective for me when I've used it.

Once the rust is gone the dupli-color pens work great for color and to seal the area.