Rust in tubes - Dawes Galaxy

[Caulkheader]

I have a Dawes Galaxy, owned from new in about 1995. It is the model with the rear brake cable routed along the inside of the top tube, entering and exiting from the top.
I have just changed the headset and noticed whilst it was on the stand that there was a great deal of flaking rust in the top tube.
Presumably this is from water getting into the tube where the brake cable enters and leaves and sitting there.

Couple of questions-
Have any members with this model had this problem and how did they rectify it?
How can I stop the spread of rust in the tube - am thinking of engine oil or waxoil?
How can I tell the extent of the damage so far?

Thanks

John

[hubgearfreak]

Have any members with this model had this problem and how did they rectify it?
How can I stop the spread of rust in the tube - am thinking of engine oil or waxoil?
How can I tell the extent of the damage so far?

1. no
2.either of those or dinitrol or framesaver
3. strip the frame to nothing. ping it like a triangle (the musical/percussion one) does it ping? then it's OK. if it thuds, then sadly, it's had it

[iron legs]

Had the same problem. Mine was in need of a repaint so I got a new top tube fitted with cable guides on top. Back on the road and going fine.

[Caulkheader]

Thanks for the replies.

John

[JohnW]

John -
You've identified yet another feature to avoid when ordering/buying a new frame/bike.

[james01]

Internal rust can be a problem with any ferrous frame. Water can enter in many ways. Even a threaded braze-on rack fitting, with the bolt done up tightly, is not necessarily 100% watertight.
There must be an element of luck. I've peered inside 30 year-old frames which have had a hard life in all weathers, and found no rust at all.

[JohnW]

Oh, yes James, I fully agree with what you say, but any feature which has caused problems is a feature to be avoided. As you say, any hole in a frame is a potential moisture access point - and condensation is a bigger problem than we sometimes think.

However, some holes are more avoidable than others and holes in down tubes and seat tubes are into tubes which are accessible to drain, and can be treated more easily. Holes into seat stays are more difficult, but I think we're aware of the potential and can spray into the holes with "Framesaver" or similar.

I've never had a frame where the top tube was accessible at either end, but they've all been sealed - assuming the brazed joints are all they should be! I would want to avoid making a hole in a tube which was otherwise inaccessible.