Propane torches are used for joining metals with soft soldering, brazing and hard soldering. They are also used for stripping old paint away by burning it, although a heat gun is preferable. Propane torches burn pressurized liquid petroleum gas (LPG), commonly supplied in disposable metal canisters.
The torch consists of a burner tip of varying diameters, from ¼ inch to 1 5/8 inch, attached to an angle tube with a handle and gas flow control valve, which is in turn connected by hose to a propane tank, or by a fitting to a disposable canister.
Burners can throw different shape and size flames for different uses depending on their diameter. Burners can produce a needle flame for precision soldering or a broad flame for joining large diameter pipe. Flame spreader attachments are available that make a fan flame shape for paint stripping.
Never light a propane torch with a cigarette lighter. Always use a spark producing flint tool. Once lit, the hottest part of the flame is a spot about halfway along it’s length, in the center of the flame column, so for maximum heat, direct this area onto the work piece you are heating.
Propane Torch Safety Tips
-Propane torches should be checked for leaks regularly. Do not use a flame for leak detection. Propane is odorless and colorless, so an odorant is added by distributors so propane leaks can be detected; leaks can be verified by mixing soap and water and applying a layer over the surface suspected. The solution will show bubbles where gas is leaking. Propane leak detectors, which operate like carbon monoxide detectors, are available.
-Store propane containers away from any heat sources, like furnaces and water heaters. Discard empty canisters properly, never incinerate them or throw them into a fire.
-Burning torches should not be left unattended. When you are done with the work, turn off the gas supply at the container before disconnecting the burner and hose. That way, all the gas in the hose will be burned off.
-Always disconnect the torch burner from the container before storing.
-Since propane is heavier than air, instead of rising out of a room, it tends to sink to the floor and accumulate if there is leakage. So it is a good idea to use some ventilation in your work area.
-It may sound like common sense, but it bears repeating: Never smoke when working with propane torches or any propane equipment.