Propano-butane mixture, which is filled in cylinders for household gas stoves, in optimal conditions, burns in air with a flame temperature up to 1200 °C. It is sufficient to work with “hard” (sredneivkino) alloys: copper-zinc (brass), silver. But to get a flame, the burner must provide good mixing of gas with air, that is, feeding them at a specific ratio — no more and no less! For easy work with small parts torch should be fine, but at the same time steady and fairly hot.
The pressure in the gas tank — 16 bar; for this case it is too large, so it is necessary to limit supplied to the burner pressure up to 1,5—3 ATM., applying welding reducer or valve from the kit smoleni ski. The jet nozzle should have a diameter not exceeding 0.1 mm. To protect it from accidental clogging at the outlet of the tank needed a filter element, for example ceramic, from the fuel fine filter of the engine ZIL-130, or a homemade — from a small ceramic grinding head. As the rate of combustion of the gas mixture is relatively small, with the rapid efflux from the nozzle the mixture might not ignite — there will be a separation of the flame and the burner will go out. To avoid this, the splitter should do so through his peripheral holes of the gas flowed at a slow speed and formed around the main gas flow ignition “crown”.