I'm a competent DIYer and have done a little small-scale ferrous and non-ferrous brazing in the past. It was in a professional workshop the equipment was provided suitable on request, so I didn't need to know how to choose the right gear.
So right now I'm looking at a few jobs around the home and household workshop scale personal work, and thinking that brazing is the appropriate technique. The work I have backlogged includes a copper/brass/bronze sculpture which has a brazed copper "leaf" shaped piece broken off where it was joined, small scale iron/steel/alum (<3 mm flat/5mm rod ferrous), and other minor and broken things from time to time. It's enough to be worth investing in a small brazing torch and other equipment, although I might only use it once or twice a year if that.
There is a huge amount of info out there on fluxes, techniques, and rods, so that's easy. But there is nothing solid that I can find, about torch style and gas choices, is the problem.
What I've found so far is, temps suitable for different materials (eg above ~ 500C and for copper below about 1000C from memory), temps for different gases (~1500C to 4000C roughly, from memory, sorry if my memory's wrong, the general idea is right I know). I'm also aware of the difference between flame temp and target temp and to expect that the metals and equipment will act as a heatsink. But beyond those basics, I can't find anything to guide me in choosing an appropriate brazing torch type and gas to use. (Solder yes. Flux yes. Protective gas yes. Technique yes. Combustible fuel and torch selection no.)
To an extent I can move the torch or adjust the gas flow to change the temp based on the flux and joint appearance, that's easy. But what features or spec items would make a torch suitable for my use, and which gas combinations are most sensible that more experienced brazers would go for? Should I look at heat output or gas flow to know if it's going to be adequate for brazing? I'm going to have very light use (< 1 hour/year?) and for now I'm not expecting heavy duty work, so perhaps some gas + air will be enough and makes economic sense. (Or should that be gas/LPG? No idea.) I might use it more on ferrous steel or filling, once I gain experience.
Which fuels are likely to be good for me? What makes the difference between a "not hot or consistent enough in actual use" torch and a decent budget-level torch? What sort of gear should my shortlist include (to look up "comparison of..." articles)
In all, I don't need more than a basic simple torch but I'd like to get one that can handle a little more than I'm expecting, rather than find after starting a job, that I've bought a lightweight plumbing torch that can't really pump sufficient heat into the joint. That's what I most want to learn.
Other relevant info might include common "warning signs" to help identify a cheap, poorly built torch, and maybe also some suggestion how much gas is sensible for me to buy (0.5 L? 10 L? I don't want to run out halfway through my 2nd job and gas lasts for ages on the cupboard shelf).
Thanks for helping