Many thanks. I've never really done much soldering like this before, so I'm chuffed to bits with the results.
You're absolutely right about the jigs, I was terrified that sticking one bit on would make another one fall off. This is also why the dropouts are 3D printed. No way would I have been able to keep them in one piece while soldering.
As for 3D printing, I think I may be mellowing in my opposition to it. I still find making things "properly" infinitely more satisfying, but I'm warming to the possibilities that 3D printing presents.
It has it's place. the problem is that it's a lot like a hammer, once you have one, everything is a nail.
I did some car parts this weekend, I could have spent a few hours in the workshop making them from aluminium which would be total overkill for it, or I could spend half hour in CAD and leave the printer working away while I did other things. Guess which one won? I now have a bright orange sun visor bracket
I have a black one too, but orange was in the printer while I was refining the design, and now it's in I can't be arsed to swap it to the black one I made. the phone holder is printed, yer it's not complex, but I see little satisfaction in making a channel with some holes in and a bit sticking out to fit in the air vent.
It's completely daft, but you do find ways to use it in projects, things like jigs, holders and such are great, they are dimensionally accurate (if you set your printer up) and stable, you aren't spending your time making them, instead you are making the parts that the jig is needed for and if it's not right, it takes seconds to fix it and walk away back to something else.
I don't think I'm about to make a model like this with one, but it's a tool to make the process around the model go smoothly.
out of complete geek interest, what temp solder did you use? did you use different temps as you progressed so the heat wouldn't melt other joints? I guess you used an iron rather than a flame. as a future time which will do a few nice things for you, clean and flux the joint (for this I'd use plumbers flux, but for silver solder it's borax cone and dish) then drop a small pellet of solder into the tube and make up the joint so the solder falls into the joint rather than away from it. Apply heat and be amazed as the solder suddenly appears in the joint and forms a delightful fillet.
I always knew it as sil brazing, but I'm not sure that's the right term now, and it's possible that it wasn't the term I remember.