There is another approach, too: Make the bike so unique it can’t be sold. Even old bikes got stolen.
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That was the plan originally but there’s currently a problem with thieves targeting nice bikes to steal parts from them. There messages from the police posted all over the parking saying that if you were a victim of bike parts theft you should make an appointment with them.
Making the bike unique doesn’t protect it from parts theft, you’ll just never lose your frame which I guess is a lot better than losing the whole bike.
My girlfriend’s bike has a few equally worthy parts on it but it just looks like a basic grey city bike so they didn’t look at it even though it was parked right next to mine.
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Is it possible to use bottle cage bosses as upper rack mounts?
Starting to prepare my list of lugs and bits and bobs which I will order in a few days but I don’t really like the typical mounts that sit on top of the stays, I much prefer ones that sit kinda hidden. My stays are 12.7x0.8mm.
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Sure. With 12mm stays you’ll have to fillet a little bit under the head of the boss but otherwise this should be fine
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Ah – and of course a 12mm seat stay is a bit fragile. But for a light duty city bike it should be also fine.
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Oh yes it’s only a bike for general around town use and some very light touring 
thanks
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I thought you were using Reynolds 525? The narrowest stays I can find are 14mm. However they are tapered, and quite long, so you can decide which end to cut off depending on how thin you want them.
Personally I use the 14mm ones if I’m not planning on running a rear rack, otherwise the 16mm for touring, or 19mm for heavy-duty use like kids on the back, and I do prefer the rack braze-ons that sit on top of the tube. Drilling it weakens it a bit, although it’s fine really because the bottle boss will give you the strength back. But I’m sure you can run a rack with 12.7mm stays and bottle bosses perfectly well. I’m just stating my own prejudices here 
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Another benefit to the hourglass style that sit on top of the tube is that if you ever screw up the threads, you can run a nut and a bolt through there. Maybe not a big deal on a town bike but can be a life-saver on a touring bike.
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@guy153 yes 525 except for the seatstays, those are plain gauge because I like the look of skinny straight seatstays. I do plan on using Reynolds 16mm stays in bikes for more demanding uses
@stevenshand good point, for a daily driver or tourer I will go that way! For this one I say screw it I wanna have fun haha
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I finally replaced the old brittle hoses in my oxygen concentrator and got propane nozzles. It’s so much better!
Now I just need a real propane bottle to hook it up to, I notice the flame gets leaner as that little bottle cools down.
For the first test I brazed a 0.2mm thick tube from an old retractable FM antenna onto a 0.5mm thick section of bike tube. Went well! Lovely little fillet, didn’t overheat either tube.
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Alright so I have a couple of these 316L printed lugs that I got printed back in april when I had the idea for the road bike with printed lugs carbon fork etc etc.
I thought if I have them anyway and I’ll never actually use them, might as well see if I can use the for practice. Tolerances around the tube were far too sloppy with pretty big gaps around some parts but I gave it a go anyway.
There are definitely some spots that didn’t fill properly, not sure if I should’ve added more filler but those were also the spots with big gaps.
I was also struggling a bit to get some parts of the lug up to temp because this one is very thick and has the big bulky material on the bottom for the idea I had for integrated bearings.
All in all not great but a good piece of practice. I don’t really feel like the fact that it’s stainless held me back but rather the overly bulky design and poor tolerances.
I also couldn’t fit a head tube through due to the little lip I stupidly put inside. Maybe with a head tube inserted it would’ve also flowed better because now I could only add filler from the side and bottom.
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Oops I’m stubborn and designed and ordered 3D printed lugs with custom angles anyway.
I kinda came to the conclusion that I’m really not interested in having another bike with a horizontal top tube. I really want a beautiful lightweight bike with a sloping top tube so I can have a comfy high stack height and plenty of seatpost extension also for comfort. Plus the more direct load path from the front to the BB and rear end should in theory make the frame more laterally stiff aka responsive and I want to feel what it’s like.
I also have the philosophy that it’s best to have the center of mass of a bike as low as possible to make the bike more responsive when you chuck it into a corner.
Might as well put in some extra time and money learning to build a bike I’m genuinely excited about rather than just a stepping stone to something I actually want.
Lugs
Very pleased with the zebra analysis. (Shows how cleanly the surfaces are modelled)
Whole bike visualisation in bikecad (final one has a touch more stack height but you get the idea)
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My cheap torch works pretty well with the proper nozzles but man the big fat plastic handle really sucks. It came loose and now it spins around separately from the rest of the torch.
So I went and 3D printed a nice new skinny hexagonal handle. My torch is a big flaming pencil now and it feels so much nicer to hold!
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Made a little baby 1:5 scale rack from old spokes as cheap silver brazing practice while I wait for stuff to arrive.
After a little scotchbrite cleanup
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Now a slightly more tricky heat control exercise!
A little sculpture made of brass brazing rods, first annealed and then brazed together with silver. I think this is a decent exercise to stay within a narrow temperature range, but of course it’s much smaller stuff that’s much easier to bring up to temperature.
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Sell those on Etsy and retire young!
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Haha not sure people would really pay much for these things 
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Also Etsy would keep most of the money They’re very nice though (I mean your artefacts, not Etsy).
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A little fillet brazing practice as well, even though I won’t be fillet brazing this bike I thought I might as well give it a go since I have the materials.
I was a bit limited by only having a basic bench vice to hold the big tube. I had to put a dab of brass on the tube, then reheat when I stuck on the small tube which meant fitup was pretty bad.
Also no ability to easily rotate the piece while I’m working my way around it.
I think I added too much heat? Not sure, this flux turns black as it activates but the area around the fillet looks more “charred" black.
Oh and this icicle I made. That went pretty well. I’ve noticed a slight touch of flux on the rod really helps.
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Okay so I didn’t see this one coming… My in3dtec shipment of printed lugs is blocked because they first need to declare that it doesn’t contain any Russian steel because Russian steel imports are banned.
Let’s hope they can provide that MILL document and that it doesn’t contain any Russian steel, because I’d have to find a different supplier otherwise.
For anyone interested:
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