I think I may have a trace of rust...

[swee'pea99]

That looks a lot better - I wouldn't expect anyone to buy the zinc primer just for a one-off. I've used it (on the underside of a steel fuel tank on my car) and it certainly works.
Does the seatpin on your bike move? I'd take the opportunity of removing it and greasing if you haven't already done so.
p.s. I saw a bike frame damaged when someone undid the allen key (like yours above?) because they didn't realise one side had a 'tag' into a slot (if that makes sense), and they took an allen key to the other side and turned, when they should have used an additional AK on the 'fixed' side.

Thanks for the heads up. I did know as 'it 'appens, but a kind thought, and much appreciated. Sadly I have to report that I went to considerable efforts to shift the seat post, some years back, with zero success. I'm kind of resigned to it now. Long as it sees me out, then someone else with the same size legs can take it over 😀

 

[SuperGalactian]

This thread reminded me of two things. First, Owatrol is very effective at sealing things against further corrosion while preserving a rusty look (or a nicely painted one if you are ahead of the decay).

Second, last time I had a (steel) frame re/-enamelled, I bought a spray can of proprietary’bicycle frame preserver’ (I forget the brand), which I applied inside all the tubes before re-assembling the bike. Then the half-empty can sat on the shelf in the bike shed for a few years. Early this year, I found a sticky mess on said shelf. The frame preserver had escaped from its can. So now I have grave doubts about its efficacy. I mean, how is that possible? 🤨