Frame rust

[Bowak]

I've inspected my frame today and have discovered several small rust spots on chipped paint. I'm not concerned by most of these and have looked up what I need to do to remove the rust and touch up the paint afterwards.

There's just one spot that while I think it will probably be fine as well, I want to run past more experienced eyes as it's on a weld where the seat stay meets the seat tube: http://imgur.com/pZAreC6 As this is tiny can it be treated the same way as a normal surface chip or would it need more careful inspection?

With the camera I had available I wasn't able to get a useable closer shot so I appreciate it's not the best view.

The bike is a 97 Dawes Galaxy and over the next year or so I'm looking at replacing a lot of the parts - all the gearing, cranks, handlebars & front wheel. Before I do this, I want to check the inside of the frame for rust too as I don't want to spend that much money without being sure the frame has a good few more years in it. I've costed the parts I'll need to be approximately £400 which is sufficiently below the cost of a new bike for me to not consider buying one instead, especially as I have a 64cm frame and found my previous 97 Claud Butler 61cm tourer a bit too small. As I replaced the rear wheel a few months ago, so long as the frame's good it'd be close to being a new bike anyway at that point.

Presumably to inspect properly I'll need to remove the seat post, stem and bottom bracket and use a torch to check the inside of the tubes? I'm assuming that a few spots of rust would be expected in a 17 year old frame, but what should I look out for as a warning that it's time to start planning for a replacement? Large patches of rust? Thinning walls? etc

I figure this'll be a good chance to actually use some of the tools I've had lying around for a few years, plus I have a week off work coming up so if I do get something horribly wrong I have time to get to a bike shop to fix it before I need it for commuting.

Thanks for all advice.

[Valbrona]

Have you got the right size seatpost in? I have seen frames crack/split there where the seatpost is a slack fit in the seat tube, and the user compensates for this slack fit by doing up the binder bolt really tight.

[Bowak]

I assume I have the right size seat post. However, it's been 3 or 4 years since I last adjusted the saddle but I don't remember it feeling loose in the tube.

Rather frustratingly I can't measure it at the moment as the hex head has rounded off.

Edit: It's also the seat post that was with the bike when I bought it 2nd hand in 2005 and may well be the original from the factory.

[531colin]

Worry not, its fine.
The joints are brazed, and braze doesn't rust, so its just a tiny bit of surface rust on the tube.

[Bowak]

Excellent, it's nice to have it confirmed as fine. Hopefully I'll get at least another 9 years out of this frame.