I am a frame builder AMA

What's the standard mount thingie specifications for a Shimano direct mount brake?

Are they the same as Paul direct mounts? To clarify I'd like to run Shimano BR-R9110-F and BR-9110-RS or similar

I have the data sheet at work, will get back to you today.

Can you build me a titanium bike for free?

That guy, what a wanker. I don't know why they even let those plums join...

I've ordered some bits from ceeway, planning to add an extra set of bottle cage mounts on the DT. There's already one on the ST and as the bosses have pointy reinforcement things I'd like to have that on the new ones too. I've never done anything like this before so I've ordered a scrap tube and some extra bits for practicing. My question is how I should go about it, do I braze the reinforcement on first and then the boss or what? Will be using silver and mapp gas.

These things:

Both at the same time, easy peas ;)

Did you find something? :D

Ok. So, flux everywhere, plonk the bits on, heat said bits until flux melts, poke with solder. Correcto?

I will see if I have time to do you a little video snippet later but you are sort of right.
Silver melts at around 550°c depending on what silver you got.
Google steel heat colour chart to get an idea of what colour you are looking for before adding silver solder.
Even if you add a bit too early you can still massage it with the flame to make it flow out.

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Reading that thinking "what the fuck is @Hulsroy on about, that doesn't happen" then remembered that I'm colour blind. It's funny how often you forget 🤣🤣🤣

Lol.
The other way, if you are wearing shades, is to wait for flux to be glas like and then poke silver on to steel until it melts. Do not melt silver with flame. Steel need to be hot enough for silver to flow out.

I've done it from state of flux, but that's dependent on experience so useless for explaining. Basically what @Hulsroy says....

https://photos.app.goo.gl/UhPYDNJcog14jiWA2

Does this work for you?
Remember I am using propane+oxygen. Your flame might look different.
Also, my inserts are stainless in this case and they have a tendency to heat up quicker than steel. That is why they are so orange in my film. They shouldn't be that hot as they won't accept the silver. Move flame away constantly and quickly if it gets that hot.

Wow @Hulsroy @coldharbour thanks! Instructional videos on demand 😁

You are welcome. Have fun!

https://youtu.be/Uldm5z2gdck

What the difference between gas welding and brazing?

Someone once said that gas welding was like tig but with a torch instead of the arc but I think tig is like brazing but with the arc instead of a torch.

Welding melts both parent materials, normally with a filler material as well. Brazing simply heats parent materials, with a filler added to hold them together.

Cheers, that makes perfect sense!

Brazing uses a eutectic filler, welding does not. Obvs.

How'd you drill a ST when adding bottle mounts? I've read that it's hard to do without a proper jig and drill as stress fractures might occur around the edges. True or false?

Also, what tubing or rods do you use for racks? Anything you can buy from Ceeway?

Also, what tubing or rods do you use for racks?

I'd like to know that too!

How'd you drill a ST when adding bottle mounts? I've read that it's hard to do without a proper jig and drill as stress fractures might occur around the edges. True or false?

I've just marked the places the holes should go and used a hand drill. A jig might be handy (if unnecessary) for getting the holes in the right places, but I can't see how a jig would prevent stress fractures. Or why drilling a hole would produce stress fractures, to be honest, provided its deburred after drilling.

I have a jig for ease of repetition, but to be honest it is only the boys that use it, I still use tube blocks on the surface plate to score a centre line, centre punch, hole starter then drill. If you stirred the drill like a wooden spoon you might be able to crack a tube, but I can't see a jig would be any different than drilling straight by hand, as long as the hole is dressed properly.