Today’s guest post is by Tim Lux with Miller Electric:
There are a few simple checks that can make plasma cutting work like a dream. Skip them, and you may be dealing with extreme frustration. Below I have listed solutions to the 5 most common problems people bring up to me when using a plasma cutter.
Setting Up the Work Clamp for Plasma Cutting
The work clamp (sometimes referred to as the “ground” clamp by customers) needs a good electrical connection. If you are cutting on rusty, galvanized, painted, or dirty material, you will need to grind off a place for the work clamp. The torch will cut its rated capacity just fine provided the work clamp has a good connection.
Plasma Cutting Consumables
If the torch consumables are worn beyond the manufacturer’s recommendation, you may experience arc outages. Normally, for tips, if the hole in the end has doubled in size when compared to a new tip, it is time to replace it. Electrodes need to be replaced when the Hafnium in the center of the electrode has reached a depth of 1\16th of an inch. Check your manual for specific information on when to change the consumables. In standard applications, you may be able to use 2 tips for every one electrode.
Standoff distance for Plasma Cutting
Typically a recommended standoff height is 1/16″ to 1/8″ off without touching your work piece. Remember electricity is lazy. It wants to take the path of least resistance. If you get too far away from the work piece, resistance between the work piece and electrode (cutting circuit) is much higher than the resistance between the tip and electrode (pilot circuit). This will cause the machine to stay in pilot and shut off after the five seconds.
Retaining Cup for Plasma Cutting
If the cup is on too tight it prevents the electrode from moving freely. This will, in turn, prevent the arc from transferring. When threading the cup onto the end of the torch you should be able to feel and hear the cup switch in the torch click. Once this switch has been closed the cup does not need to be tightened any further.
Plasma Cutter Air Supply
If there is any moisture in the air supply, it can prevent arc transfer and create arc outages. Excess moisture in the system can also lead to premature consumable wear and cause the tips to wear unevenly, leading to problems with the kerf angle of your cut.
Following these simple guidelines will help you ensure that your machine operates to its full potential and will help extend the life of your machine and consumables.
Learn more about Plasma Cutting at Baker’s Gas and Welding
Find the Right Plasma Cutter in the Baker’s Buying Guide
About Today’s Guest Post Author
Tim Lux has been with Miller Electric for over 25 years. While the majority of that time has been spent with Millers’ industrial products service and end user training department, Tim currently is the service and applications specialist with the Plasma group at Miller.
