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Using a cutting torch is serious stuff. Its pretty Safe when used properly, but not safe at all when not used properly. This is not a comprehensive oxyfuel safety course by any means but I tried to include most of the main things

Oxy-fuel cutting and oxy-fuel welding can be described as the processes of using oxygen and fuel gases to either cut or weld metals. There are some striking differences between these two processes. In the first process, a cutting torch is made use of for heating ferrous metal to a temperature of around 980 degree Celsius. An oxygen stream is being trained on a hot metal that combines with iron chemically which later flows from the kerfs, or cut in the form of slag of iron oxide. In the second process, a ‘welding torch’ is made use of for welding metals.

Torches that burn the inside fuel with air (atmosphere) cannot be termed as oxy-fuel torches. They stand out owing to the use of single tank. This is because oxy-fuel cutting/welding requires oxygen, fuel, and two tanks. It’s not possible to melt some of the metals with single-tank torches. Hence, these torches can be used for brazing and soldering, but not for welding. A metal-cutting torch is better known as hot blue spanner, blue wrench, hot wrench, smoke wrench, and gas-axe.

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Types of Torches: The torch can be defined as the part held and manipulated by the welder to get the weld made. It possesses a valve and connection for oxygen and the same things for fuel gas, a handle to obtain the grip, an integrating chamber (angularly set) where there occurs a mixing of oxygen and fuel gas, with a tip where formation of flame takes place. The fuel gases used along with oxygen include propylene, propane, hydrogen gas, MAPP gas, Liquefied Petroleum Gas (LPG), and the most widely used is acetylene.

Injector Torch: It can be defined as an archetypal oxy-fuel torch, also known as an equal-pressure torch. It carries out the mixing of mere two gases. The injector torch operates in such a way that high pressure oxygen comes out of the tiny nozzle present in the torch head, and the fuel gas gets dragged towards it via the venturi effect.

Rose-bud Torch: The use of this torch is to carry out the heating of metals for straightening, bending, etc. It is generally used where a huge area requires heating. It produces a rose-bud shaped flame at the end, hence the name. This torch can carry out the function of heating small areas like rusted bolts and nuts as well. However, here, filler rod won’t be used with torch.

Cutting Torch: The head of the cutting torch is used for cutting metal. Its identification details are as follows: The inside of the torch consists of a combination of oxygen and acetylene. It helps in producing flame of a high temperature. It consists of 3 pipes going to a nozzle at 90 degree. It also contains an oxygen-blast trigger which blasts away the material during its cutting by the way of providing oxygen.

Welding Torch: The welding torch consists of either 1 or 2 pipes running towards the nozzle without oxygen-blast trigger. As the name suggests, it performs the function of welding.

how to cut metal with an oxygen and acetylene torch. This is just a basic overview of how to use an acetylene torch to cut metal. cutting 1/2 inch steel with a torch and also how to pierce metal with the torch. This is a cheap harbor freight welding torch

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Lighting the torch & setting the flame: (FIRST, put on gloves, goggles, long pants, etc!)

1) Turn on the “gas” tank valve about 1/2 turn (believe me that’s plenty)(set the gas at 10-12 PSI).
2) Open the O2 (oxygen) tank valve nearly all the way. (set the O2 cutting pressure to about 40 PSI, via the twist knob at the O2 gauges).
3) With your striker (lighter) in one hand, crack open the acetylene valve on the torch handle & light it. (red hose).
4) Open the acetylene more till the flame separates from the tip, then back it off till it “re-attaches”. (that’s the max you can get from the tip you’re using).
5) Now open the O2 on the torch handle till the blue flames are short & bright. (green hose)
6) Then push on the long high pressure valve on the handle &  re-adjust the O2 valve on the handle till the blue flames are clear & bright.
7) You’re THERE!

Check to see that all the holes in the tip end are allowing full flow. If not, shut it off & clean the tips.

To shut the torch off: close the “gas” valve on the torch handle, then the O2 valve. Then I usually crack the high pressure valve (on the handle) to blow out any gas left.

Using the cutting torch:
1) Look around to see where your sparks will be going & protect stuff or move it, if needed.
2) See that the piece you cut off has a safe place to drop. (If you catch it you will want to put it down right away).
3) Now, put the tip of the blue flames on an edge of the material & let it get red hot (or start sparking).
4) Then push the cutting valve & slowly start moving in the direction you want to cut.
5) The thickness of the piece will determine how fast you move. But keep moving fast enough so that the sparks are flying at least straight down, or actually angled slightly ahead of the tip.
6) If you go too slow, the molten metal won’t clear out & will tend to still hold the pieces together at the end of the cut.
7) Going too fast will cause the sparks to lag behind the cutting tip, & not cut through good enough.
Note that I tend to very slightly angle the flame & tip in the direction of the cut. For me this helps to pre-heat the metal & keep the sparks angled slightly forward.

Once you’ve practiced a few times, the cuts will look pretty decent.
* You will then be able to think more about using various ways to help you steady your hands & use guides.
* Using 2 hands is a common practice of the pros.
* Using a heavy bar as a guide is a quick way to help you make a straight cut.
* Also using clamps on various other straight edges, like angle iron or channel, can help too.

Other torch and cutting tips:

1) For long cuts on plate steel you may need to use a clamp across the beginning of your cut to  hold things in place more firmly.
2) I use a torch many times to cut heavy material instead of a band saw, then do some grinding to dress it up.
3) Use a chalk line to mark really long cuts.
4) A regular cutting tip can also be used for heating smaller jobs, just keep away from the cutting valve.
5) When you get better at the “trigger control” of the cutting valve, you can use it to gouge out cracks for better penetration.
6) You will need to get a O2 bottle that is at least 1/2 again as tall as the acetylene bottle because you will be using MUCH more O2 versus gas.
7) On thicker materials you can use your torch to bevel the edges for better penetration (versus grinding).
Lots of popping sounds & splatter likely means that your tip is too close to or touching the molten metal (or your tip orifices are plugged, or BOTH).
9) Make sure when you have your tanks off, that the gauges read ZERO! (example: if the O2 reads 20 when it’s off, then when you set the 40 PSI cutting pressure, you really only have 20 PSI that you’re cutting with! This happened to me).
10) When you need to cut off just the weld of a job, it takes a CAREFUL touch of the cutting valve & you need to watch for where the pieces join each other & try to not cut into the pieces you’re trying to save.

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