Making Cut

Before you do anything, you will want to check your environment for hazards and flammable materials. Set up what you will cut and ensure it is at least 10’ from your cylinders.

Set your fuel and oxygen to the appropriate settings using the manufacturer’s directions for the torch you are using. As an example, see the Victor Acetylene Cutting Tip Chart at Eureka Oxygen Co. as an example.

Light the torch with your friction ignitor and follow the steps from the Setting Up the System section of this chapter to establish a neutral flame.

Depress the oxygen lever; you will see the cutting jet at this point, but the preheat cones should change minimally. If the flame is abnormal, you may need to shut off the torch and clean the tip.

Preheat your material. Use this time to practice making the cut and getting as comfortable as possible moving the torch over the area you wish to cut. The flame of the torch should hit the material in a perpendicular fashion with the preheat cones hovering above at double their length from the tip to the material. Move the torch over the material slowly three or four times. You do not want to overheat the material as this can cause problems when cutting.

Stop at the edge of the material and let the edge heat to a bright orange just before it starts to turn yellow, then depress the oxygen lever.

Slowly move along the line that you wish to cut, holding the torch 90 degrees to the metal. (If you are cutting thinner material, you can angle the torch in the direction you are cutting to simulate a thicker piece of metal.)

As you complete the cut your material should fall away. This will not always happen for a variety of reasons. Inspect your material and the edge that is left behind. This is your kerf angle. This should be fairly smooth and consistent with small ridges.

Here are some examples. Good, bad, and otherwise made with a track torch to simulate some possible mistakes that are commonly made.

These are not the only problems that can happen. Here are some other issues you could experience while cutting with OFC-A

• Not completely penetrating the metal, you will probably want to increase your oxygen pressure and slow down a little.
• The material is welding itself back together, a possible solution, increase travel speed and hold the torch slightly farther away. A common mistake is to hold the torch too close to the material. This could also be caused by overheating the material before you try to cut.

You will need to practice making cuts as cleanly as you can. There are many techniques you can utilize, and you should get comfortable with as many as you can. Some work better in certain situations than others.

• Push the touch through your support hand very slowly.
• Pull the torch through your support hand. You have to be cautious with this technique as it will put your hand very close to the cutting tip at some point.
• Rotate the torch in your hand to make a straight cut or to go around a piece of angle iron.
• If you want to make a pierce, try the following technique. Preheat the spot that you wish to make your hole in; this will take a little longer than heating the edge of the material. Once the metal is a bright orange, tilt the torch slightly away from you and depress the oxygen lever slowly. Tilting the torch at first prevents dross from being shot up into the torch tip. Once you have pierced through the material, adjust the torch to 90 degrees in relation to the cutting plain and cut on the inside line of the shape you are trying to cut.

Special Safety Concerns at the Torch

The two most common hazards associated with oxy fuel are fire hazards and burns. The cutting process creates an enormous amount of sparks that can cause fires. Make sure you are aware of your surroundings when performing this work.

Alway wear your PPE. This includes but is not limited to Shaded goggles, welding gloves and welding jacket.

Maintaining the System

There is very little maintenance required for oxy-fuel systems.

Make sure everything is put away neatly and inspected before every use. Replace anything that has been damaged.

Attributions

1. Figure 12.12: Quality Cut by Karl Fulton, for WA Open ProfTech, © SBCTC, CC BY 4.0
2. Figure 12.13: Too Slow and Too Close by Karl Fulton, for WA Open ProfTech, © SBCTC, CC BY 4.0
3. Figure 12.14: Too Fast with Multiple Restarts by Karl Fulton, for WA Open ProfTech, © SBCTC, CC BY 4.0