For those who know how to braze

I learned back in the 1970s as part of my apprenticeship at the Royal Ordnance Factory Nottingham, ROF (N). I opted to become a sheetmetal worker and spent the next 4 years in the sheetmetal shop fabricating components for such projects as the 105mm Lightweight gun, Eager Beaver military forklift, Chieftan Bridgelayer, Combat Engineering Tractor (CET) etc.
After 4 years at college (City & Guilds Fabrication and Welding course FWT4) and 3 years piecework - I got fed up of being under a TIG welding helmet and went to Rolls-Royce working on jet pipe fabrication.
It's all a long time in the past now but I stayed in aerospace (behind a desk - up the management ladder and down again) until retiring a few years ago.
What's all this got to do with brazing? - well there's an awful lot to learn about so called "brazing", different alloys/temperatures etc for different applications. I've never researched the filler alloys used for bicycle frame construction so on that point I'm ignorant but I've used brass alloys (bronze welding), silver alloys (silver soldering or hard soldering, often referred to as brazing but technically not).
As a first step I'd try to find a good Metal Joining Handbook and from it identify which processes suit your eventual goals, then set yourself up and practice, practice, practice....
Quite the CV!
I bet there's some serious arcane knowledge that comes from working in a shop like that.
I guess some serious equipment too..
As you say the variety and amount of information available and terminology used is dizzying.
Looking for handbooks is a good idea though, sometimes the Internet is too much so a book may provide clearer answers.
 
my dad taught me. certified welder on gas and SMAW.
yer you can teach yourself, but you'd be better spending on a few hours with pro at you elbow. Gas welding/brazing especially can be really really scary when you get it wrong, in fact it can be scary when you get it right.

if you want to do real brazing (as in not soldering) you'll need real equipment and don't forget to tell you house insurance, especially if you go down the acetylene route. for small stuff (and yes you can do bikes) you could be just as well going down the oxy propane route.

have you thought about TIG? :)
Yeah I think a few pro hours would equate to like a hundred of self taught.
I'm totally unfamiliar with all this stuff so it's all scary to me!
If I was going to invest it would be propane. Acetylene seems like more the industrial professional choice-not something I want to have to worry about.

I did consider tig, but the learning curve seems really steep? That seems like something you'd absolutely need lessons for?
Highly versatile though.
 
Similar to above was taught during my mechanical apprenticeship ship on all forms of metal joining from
Brazing Bronze Welding, silver solder, Tig & mig, Acetylene welding & Arc. I was always good at Arc & can still do this pretty well.

Sometimes frame builders will do courses so look at for these as they need to get alternate form of income
I've had a look at some courses, some really skilled builders doing them actually.
Problem is the price really. Definetely Justified for the time, materials, and skills you get out of it, just not a cost I can match unfortunately. One day perhaps.
 
In college I took an oxy-acetylene welding class. One segment of the class was on brazing. I've done very little welding or brazing since then and have not practiced enough to be proficient by any means.

The important take away I got from the class was that the gas bottle regulators and torch tips are critical. Both oxygen and acetylene regulators must be designed to use at 1-10 psi (as welding & brazing takes place at 2-6 psi). Most all hardware store welding kits come with a decent acetylene regulator but the provided oxygen regulator is only stable above 15-20 psi (usually intended to use for cutting rather than welding).

I did get an oxy-acetylene kit and separately purchased the oxygen regulator and several #0 and #1 tips. I recommend the same for anyone looking to do the same.

Good skill is found through experience and advice from experienced welders to learn the behaviors of different metals, welding rods, flux, substrate preparation, heating techniques, torch handling, etc. Don't be daunted; if you have the desire to learn do go for it.
 
In college I took an oxy-acetylene welding class. One segment of the class was on brazing. I've done very little welding or brazing since then and have not practiced enough to be proficient by any means.

The important take away I got from the class was that the gas bottle regulators and torch tips are critical. Both oxygen and acetylene regulators must be designed to use at 1-10 psi (as welding & brazing takes place at 2-6 psi). Most all hardware store welding kits come with a decent acetylene regulator but the provided oxygen regulator is only stable above 15-20 psi (usually intended to use for cutting rather than welding).

I did get an oxy-acetylene kit and separately purchased the oxygen regulator and several #0 and #1 tips. I recommend the same for anyone looking to do the same.

Good skill is found through experience and advice from experienced welders to learn the behaviors of different metals, welding rods, flux, substrate preparation, heating techniques, torch handling, etc. Don't be daunted; if you have the desire to learn do go for it.
That's really useful actually, the kind of details that are hard to find. I've seen a few kits online that look pretty cheap, but at least now I know what to look out for.
I take it #0 and #1 tips are the sizes, and it's just general gas torch tips?
 
If you're ever near Bristol I could arrange a lesson, preferably a saturday morning in winter.
We've got plenty of bicycle frame tubes and lugs.
That would be really great actually. I live on the other side of the country unfortunately but I'm sure I could find an excuse to be around there.
 
I did consider tig, but the learning curve seems really steep? That seems like something you'd absolutely need lessons for?
Highly versatile though.
Don't believe the guff about TIG being hard, if you have good hand coordination it's not that hard to master. Yes lessons will help but just a few hours one on one with someone who can TIG weld would be enough to get you started.

In a way TIG and brazing are kinda the same process, I'm right handed so I heat with the right and feed filler material with the left. With brazing the heat comes from a gas flame and TIG it's an electric arc.

I learnt TIG with a scratch start DC set, my first proper job was at a metal fabricators, I did the donkey work making bits that others would weld together, I was being nosey one day watching the boss TIG weld with a spare mask and he noticed me and asked if I wanted a go ?

We got some scrap bits and he set the machine up for me and told me what to do and I had a go, I soon learnt how to sharpen the tungsten as I kept sticking it to the work at first but after an hour or so I could do a passable weld. As time went on he explained how to set the machine up etc etc and I've been welding ever since.

Stainless is nicer than mild to TIG weld, aluminium is harder and you need an AC set. HF start is much nicer than scratch start or lift start, less chance of contaminating the weld with the tungsten so I'd always choose that.
 
Don't believe the guff about TIG being hard, if you have good hand coordination it's not that hard to master. Yes lessons will help but just a few hours one on one with someone who can TIG weld would be enough to get you started.

In a way TIG and brazing are kinda the same process, I'm right handed so I heat with the right and feed filler material with the left. With brazing the heat comes from a gas flame and TIG it's an electric arc.

I learnt TIG with a scratch start DC set, my first proper job was at a metal fabricators, I did the donkey work making bits that others would weld together, I was being nosey one day watching the boss TIG weld with a spare mask and he noticed me and asked if I wanted a go ?

We got some scrap bits and he set the machine up for me and told me what to do and I had a go, I soon learnt how to sharpen the tungsten as I kept sticking it to the work at first but after an hour or so I could do a passable weld. As time went on he explained how to set the machine up etc etc and I've been welding ever since.

Stainless is nicer than mild to TIG weld, aluminium is harder and you need an AC set. HF start is much nicer than scratch start or lift start, less chance of contaminating the weld with the tungsten so I'd always choose that.
Maybe worth having a go then!
Certainly seems to be the more versatile of the two joining methods.
I imagine it will be easier to find someone who can teach me welding than brazing too.
One thing that has stopped me before is the setup cost seems higher, like £500 minimum. But I guess maybe worth it for the versatility.
 
Maybe worth having a go then!
Certainly seems to be the more versatile of the two joining methods.
I imagine it will be easier to find someone who can teach me welding than brazing too.
One thing that has stopped me before is the setup cost seems higher, like £500 minimum. But I guess maybe worth it for the versatility.
setup costs for brazing are about the same.

if you want to make a frame with lugs learn to braze, if you want to make a bike in more modern guises, learn to tig.

personally, I'd go with TIG. the entry price maybe high, but the ongoing prices are much lower (cost of tungsten isn't terrible and argon can be had at a reasonable price).

one day I'll get my own TIG set here, but for now I'm stuck with MIG and arc, neither of which is going to build me a bike frame. :)
 

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