Bicycle Mechanics - Rusty seat tube, how much $?

Hello folks,

I know this has been discussed, I did do a search, but I have a two-part question and the second part doesn't seemed to have been answered in past threads.

I have a few year old entry level road bike made from Reynolds 631. (It's a 2004)
I noticed that inside of the seat tube there is some rust forming. I also noticed some around the rear brake mount. My bike lives inside but it has been ridden in the rain plenty. I assume that it is superficial simply because of the young age of this bike.

Here are my questions:
If I take to the shop that I bought it from, what are they likely to do? And how much will it cost me?

I want to save this frame. Is this something that needs to be taken care of immediately?

Thanks to anyone with the patience to answer yet another rust question.

Is it just surface rust, or is it like boiling rust. I don't think there's anything can be done for real rust, other than replacing the tube (if it's a lugged frame).

I think it is just surface rust but I'd like to keep it from getting any worse.

For the interior of the frame tubes (not just the seat tube) there is a spray-on product called Weigels Frame Saver that is a wax based, rust inhibitor containing "undercoat". It's available at many bike shops. There is an identical product called Amsoil HDMP available at many independent auto parts stores too.

To apply it, strip the frame of its components and spray the stuff into the inside of all of the tubes including the chain and seat stays (through the vent holes) and the fork if it's also steel. Let the excess drain and dry it for a day or two.

It will seal existing rust and prevent further rusting. A good steel frame is worth the trouble.

For exterior rust, sand or steelwool off the loose rust and cover with touchup paint.

I have cleaned rust from the inside of seat tube by taping a piece of medium grit sandpaper to a
1/4 " rod and wrapping the paper around the rod put it in a drill or you can twist by hand, insert
into the seat tube and turn it to remove the rust.

A shotgun cleaning rod with a 10-gauge barrel brush is also a good tool for cleaning bike tube interiors.

Just spray the tubes with WD-40, grease the seatpost and forget about it.

Enjoy

The rust needs to be dealt with. I second the mechanical cleaning options but suggest, in addition that you look for some phosphate based rust converter solution (Naval Jelly is one brand, Oxi Solve another and others are around) and swab out the innards as best you can with this and let it dry. This will convert the rust to iron phosphate, slowing new rust formation enormously, and is a good surface on which to spray the Frame Saver stuff. Since your frame has already rusted it is at high risk for further rusting, so I would spend a bit of effort and $ to preserve it. WD40 is not a good solution for frames in the condition you describe, it works fine in Arizona however. You need to pay attention to the seat and chain stays, hopefully there are access holes at the BB for the chain stay. Seat stays may well be sealed, as likely as is the fork, if steel. The seat tube is the most accessible of the tubes, the top tube difficult or impossible, the down tube, probably from the BB. Head tube is accessible. You will use up most of a day taking down the bike, cleaning and treating, but it will last a few years longer if you do so.
Steve

A shotgun cleaning rod with a 10-gauge barrel brush is also a good tool for cleaning bike tube interiors.

Just make sure the bike's not loaded.

Perhaps your frame is reacting to the metal in your seat post? Galvanic something or other.

Well, my LBS doesn't give a hoot about the rust. They suggested spraying it with WD-40.
The reality is that from their perspective the sooner I need a new bike the better.

I'll take care of it myself.

Thanks to everyone who contributed to this thread. I'll combine this information with the other rust threads I found by searching and figure something out.