Hi, I’ve been doing some research about this but I couldn’t find anything about it on this forum.
I want to start practicing brazing some lugs, but I’m struggling with finding the right torch setup.
I don’t have any plans to build a lot of frames, probably one every few years so I feel like investing in a whole oxy/propane setup is really overkill and It’ll never deliver its full value for me.
So I’ve read everything ranging from absolutely not possible, to it’s possible but not ideal, to yes absolutely no problem.
But to anyone who has some experience: what’s your opinion? I’ll be using relatively thin tubing for road/gravel frames, 56% silver and 3D printed stainless steel lugs including dropouts.
I hope I don’t sound too negative, but you are really setting yourself up for failure - the wrong cheapo crap torch, thin tubing, and stainless lugs as a beginner !
Hi, I have done my first brazing with a MAP torch and with 56 silver it works just fine but there are some drawbacks:
The nozzle on the commonly available MAP torch is huge and it will heat up a large area, it’s hard to control
56 silver is VERY expensive, you are talking about lug frames so that’s ok as you will use a small quantity of it but just FYI, it will cost you a lot.
You are starting steep with SS tubing and 3D printed lugs!!
What I mostly used my MAP torch was to braze cable stops and small parts as I was using tig mostly at the time (and not doing major jobs anyway)
I now have a more serious setup with an oxy concentrator:
All in I am up and running with $290 plug the propane tank that I already had and I have a setup that will last me forever and that will only require a propane refill to keep working.
Agreed. You’re diving into the deep end. Don’t handicap yourself with a cheap torch. There are many ways hobbyists can pinch pennies to make frames, but scrimping on a torch setup isn’t one of them. This stuff can be found used for not too much money.
Alright fair. I was looking at new stuff and breaking my head about what goes with what but I suppose if I keep an eye on second hand sites it’ll be much better to get a complete second hand set.
There’s currently this one for sale within cargo bike distance from my home but it looks pretty crusty:
I don’t know that torch but it seems that it could do the trick, you will need to research if it’s compatible with anything modern otherwise you won’t find replacement tips or different size tips.
I would not trust the regulator and most often than not the tank is replaced when you refill but depending on age they may not want to deal with it.
I am not sure if in Belgium it’s easier to find this stuff but where i live all the used torch setup are big ones while we mostly need small torches, jeweler-level kind of stuff.
You won’t regret spending a little extra on basic items like a torch, I personally would prefer to get a chinese J-28 clone off amazon for $40 to get started, at least you know that everything else is compatible and you can upgrade the torch in the future if need be without replacing everything else as well.
Have you tried contacting a frame builder near you? They may have older setups or torches that they can sell you and the explanations/contacts you make could be valuable to same time and money in the future.
Unfortunately very few framebuilders around here these days, there used to be many bike shops who build their own frames but that ended a few decades ago when aluminium took over as the most popular material. I only know one local framebuilder and they only do high end (€5000) welded frames…
Don’t know the brand, I wonder what size it is, from the knob placement I would say it’s too big but from the pictures it looks like a smaller size.
What I have found is that it’s better to stick with the well known models and brands as it’s easier to source everything else that goes with it. Unless you know what you are doing I would stay away from unknown products.
What I would do is to find a local jeweler or maybe a FB group or forum in Belgium about jewellery, they will know better what is around you - maybe another brand is more common, I don’t know.
Before building my oxy-propane setup I watched a lot of videos about different setups and they all were for jewelers, either pro or hobbyist, that gave me an idea of what to expect
Edit: Also HVAC professional may have some answers, I know most of them may use J-28 style torches for their work.
Oh wait I just remembered I bought this little set a few years ago to fix little things but I stopped using it because it’s not powerful enough to do real work with and there’s something wrong with the connection with the little oxygen tank.
Do you think I could get that to work if I hooked it up to some proper tanks and a bigger nozzle?
Edit: Are they even the right nozzles for propane? I think I see online that acetylene nozzles have one hole and propane ones have more little holes around the edge of the nozzle and this set comes with nozzles that have just one hole. I was never able to get a good powerful flame with these nozzles because no mater how carefully step by step I turned up the flame it would blow out when it got to a kind of decent size.
You should get in touch with https://www.lafraisecycles.com/
They are nearby in Roubaix. HBM makes a lot of barely useful tools.
I know some of the fun is trying to source everything on a budget, but maybe if time is valuable just take a class at lafraise?
Might be a lot cheaper in the end and for sure you will learn a lot and get to see someone braze in person which really helps.
If you want to make it more of a holiday, ETBACADEMY – Escuela Técnica de la Bicicleta
Is in Madrid and also really fantastic. They speak excellent English and the shop is really well equipped.
Hahn Rossman
Yeah I’ve seriously considered a course at Lafraise but I think because it’s a hobby and I’m in no hurry, I’ll have more fun just trying stuff at home, there’s a bunch of kinda experimental crap I wanna try with the printed lugs with ovalized tubes etc.
I know it’s gonna be a long journey that’ll be more expensive than I want it to be and occasionally frustrating and maybe even a bit wasteful sometimes (which I do feel a little bit bad about) but I love just tinkering around at home and learning the hard way. It’s how I learned to put bikes together as well and I learned so much valuable stuff along the whole process. (And am still learning of course)
I bet you could reuse that torch with different regulators and tanks!
Also, FWIW, you CAN silver braze a lugged frame using a MAPP/Air torch. The Richard Talbot book describes this method. This high-school class uses the same method too – https://www.instagram.com/farmingtonbikes/
This setup is how I learned to braze. It really does suck just as much as everyone here is saying. it’s about a grand for 60/75 tanks, silver, torch kit, and flux. more for the buckets and buckets of abrasives you’re going to go through, and files. They sell small kits designed for plumbers and hvac work which are cheaper.
