How To Use A Plasma Cutter? Tips And Tricks

Plasma cutting machine has been proven to be superior to many other cutting methods with regards to precision, low cost, or its ability to cut through thick metals.

And another strength of this amazing machine is that it is so easy to use if you know where to start with. This brings us back to the main content of this post about how to use a plasma cutter properly.

Firstly, we believe that before getting to know how to operate a plasma cutter, you should have some basic information about how your working companion- the plasma cutter itself – operates.

How Do Plasma Cutters Work?

Plasma cutters use DC voltage to elevate the temperature of the compressed air or gas to the point that it turns into a plasma state. Plasma, a form of materials, is heated to high temperatures and is optimally ionized, transferring the arc power to your workpiece. The flow of such ionized atoms passes through the narrow hole of the cutting tip where its speed is accelerated dramatically.

As the metal being cut is part of the circuit and is electrically conductive, the electrical conductivity of the plasma causes the arc to be transferred to the workpiece. This high-speed gas then cuts through the melted metal by melting it.

What Materials Can I Cut Using Plasma Cutters?

The materials that plasma cutters are typically used to cut are:

  • Steel
  • Stainless Steel
  • Aluminium
  • Brass and copper
  • Other electrically conductive materials

How To Use A Plasma Cutter For Beginners?

PSI and AMPS

Have an overall check of the working pressure of the plasma cutter you to see if it matches with the air compressor. If it is a big industrial one with the psi range being 75 or 80, and you only have a small air compressor, there is a high chance that the plasma cutter would run out of the air when cutting.

Of course, if your plasma cutting machine features a built-in air compressor, then you do not have to pay any attention to this problem. The psi also decides the metal thickness that the plasma cutter can cut through. Check out the following charts for more information.

Plasma cut thickness chart for reference

How thick the machine can pierce through also depends on how you set up the amps. There is a simple principle here that thicker cuttings require higher amps.

However, rather than adjusting the current in your machine, you could just simply adjust the travel speed of the torch when plasma cutting to get cuttings with different depth out of the same amps.

For example, at 50 amps, you can cut through a 1/32” thick metal with a very quick travel speed of the torch, and 50 amps can also work out on 25/32” thick one with much slower travel speed.

Put On Protective Gear

Before executing plasma cutting, for the sake of your safety, do not forget to wear protective gear. Usually, these three following items are irreplaceable.

  • Safety glasses: Protect your eyes from brazing light
  • Respiratory mask: filter out vapours, fumes, and dust coming off the cutting process
  • Gloves: protect your hand from extremely high-temperature heat

How To Perform Plasma Cutting?

  • Place the workpiece on the plasma cutting table

Place the workpiece on the prepared working surface, use the metal clamp to hold it down tightly to the surface. Make sure that there is free space beneath the part of the metal that you want to work with so that the arc will not bounce back.

Plasma cutting table

  • Drag cutting and hover cutting

You can either drag the tip of the torch directly to the metal piece you want to cut or hover it above the workpiece. People usually think that hovering can better save the lifetime of the machine’s consumables, but drag cutting holds some advantages.

First, drag cutting blocks out the site of the arc so your eyes are spared from being exposed to extremely bright light.

Second, it is easier for people who do not have a stable hand as they just need to drag the torch right along the lines they want the cuttings to be. And that means the cuttings are likely to be more precise this way.

However, remember to check out whether your plasma cutter accommodates this technique and put on a shield cup for your torch’s tip when you decide to go for drag cutting.

We highly recommend that you use a straightedge to help you get more accurate cuttings.

  • Execute cuttings by moving the torch on the workpiece

Move the tip of the torch along the lines you want to cut through. But you may worry that you are so inexperienced in plasma cutting and do not know whether you have the right amps set up and how fast should your torch travel.

Be reassured that as long as you follow all the safety precautions, there are no harms in not getting the perfect cuts the first time. Like any other skill, you get to learn plasma cutting through trial and error.

Practice helps you to get clean cuts

However, the tip here is, unless you are cutting something really thin, just go for average travel speed. You will know whether you are going too fast if sparks are flying out from the tip instead of coming straight down through the workpiece.

Typically, when cutting, people usually start off at the side of the workpiece and move inwards.

However, if you want to start at a point in the middle of the metal piece, you need to angle the torch to initiate the arc and then adjust it back to vertical as the metal has been pierced through. This way you can avoid the arc bouncing back and ruining the tip of the torch.

Angle the torch to pierce through a thick plate

  • Pay attention to the materials you want to cut through

Stainless steel is difficult to get through no matter what tool you use. In this case, a slower travel speed might help. Since cooper is softer, you should move the torch more quickly.

Conclusion

Hope that with all the tips and tricks we have provided about how to use plasma cutting machine, you can feel much more confident when using this amazing machine!

Have fun plasma cutting and stay tuned to our next sharings!

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