The most affordable equipment required for brazing

propane

I'd like to have an economical brazing torch for small jobs. I've been reading that propane & air is the new acetylene or mapp for brazing.

This item on Grainger mentions propane/air as the fuel, but this is a little inconsistent with other sites' listings for the same item:

Also, I feel like the image is deceiving me as to the complexity of the product. I don't understand how a few hoses and brass can amount to anything over $30. This one is listed at almost $400!

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  1. Is this the minimum product/investment necessary for brazing?
  2. Besides a tank of propane, is it the ONLY product that I need?
  3. How is the compressed air supplied?
  4. Are the threaded nubs on Acetylene, MAPP, Oxygen, and Propane all the same such that the hose fittings are interchangeable? How about the regulators?
  5. Does the standard grill-tank propane tank threaded nubs work or are smaller canisters required?

Best Answer

The main difference between most torches is the maximum temperature it is capable of handling. So you can use propane as the fuel in MAPP torch (which burns hotter), for example.

The second difference will be whether it uses compressed oxygen, or just the air around it. If it uses compressed oxygen it will burn hotter.

Approximate burn temperatures ( as found on Wikipedia )

  • propane/air 3,630 °F (2,000 °C)
  • MAPP/air 3,670 °F (2,020 °C)
  • propane/oxygen 4,530 °F (2,500 °C)
  • acetylene/oxygen 6,330 °F (3,500 °C).

For more information read http://en.wikipedia.org/wiki/Oxy-fuel_welding_and_cutting

There are also some differences in the construction of torches that make them more suitable for use with some fuels over others.


For brazing, I would start out with one of those propane/air, or MAPP/air torches that just screw onto the end of those small bottles you find at hardware stores. They are usually packaged with a bottle of fuel, because they are so cheap.

If you then find that those don't put out enough heat, or you're constantly going through bottles of fuel, then upgrade.