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Dirt
06-18-2014, 09:07 AM
One of the things that I've really enjoyed about changing up my shop life is getting back into wrenching on a daily basis. I am an odd beast... I'm happiest when I've got 11 different kinds of filth under my fingernails.

Yesterday's filth was red in color and corrosive in nature. Rust!

https://farm3.staticflickr.com/2926/14448498885_2328f7a974_b.jpg
Chicks dig rust!

The above photo was from a 1987 Raleigh that hadn't had the bottom bracket serviced since new. The frame is structurally sound and it is now much happier. Rust will always be a problem in this part of the country with steel frames.

Preventing: There are treatments and coatings that help prevent rust. Weigle's Frame Saver is the best known. Peter Weigle is a frame builder of amazing skill. He created a spray that coats the inside of a frame to prevent rust. Boeshield T9 is another that I've used successfully. Home Depot sells a rust inhibitor that works pretty well too. These should be used when the bike is new, and then re-used once per year when you tune up your bike.

Treating Rust when you've already got it: Inside the frame that is tough to do. There are products that convert rust to a non-corrosive metal oxide. They work VERY well, but are somewhat difficult to work with. Rust Remedy is the one that I've used most often. I get it at my local auto body supply store. It is a 2-part liquid that you combine in the correct ratio, then paint onto a rusted area. It can be poured or sprayed into a frame tube and then let the excess drip out. After it dries, you can spray with Frame Saver or Boeshield and then reassemble your bike. Be careful with Rust Remedy around the bottom bracket threads. The build-up of rust and rust remedy will gunk up those threads. You may have to have them professionally chased (the process of re-cutting the threads). Most shops charge $40-50 to chase a bottom bracket. The whole process doesn't damage the frame at all. It just costs you money.

Generally before reassembling a bottom bracket in any steel bike frame, I tend to coat the inside of the bottom bracket shell with waterproof grease. That is one extra layer of protection. That's something an old friend taught me. I honestly don't know if it works. I've done it for 35 years. I suppose I should research to see if there's any help or harm in doing that. I've never found a harm. I freely admit that I am doing this because I've always done it... and so did the guy who taught me to wrench.

The other kind of rust that we often see is surface rust. I have some old bikes that have rust bubbling up through the paint where there was damage. I haven't ever seen this get to the point where it is tructurally problematic on any of my bikes. It is not exactly pretty. Anything you do to fix surface rust will require some combination of rust remedy, primer, sanding and paint to finally cover and protect the repaired area. I've done that with some frames. Usually I tend to send the frame off to be painted if it is one that has a lot of personal or monetary value to me.

Happy riding! Hope that helps.

Pete