Headtube, BB, and seat tube care

[John DelGato]

Once I have sanded/stripped inside of these tubes, what's next? Seems like something should be applied to seal the bare steel.

 

[MattiThundrrr]

Surly recommends an application of rust inhibitor, such as specific frame saver products, or boiled linseed or motor fogging oil.
https://surlybikes.com/info_hole/spew/spew_care_and_feeding_of_your_steel_frame

 

[John DelGato]

I have easy access to BLO. I may start there.