Do you need to replace your CNC plasma consumables?
As your plasma cutting jobs progress, you may start to notice your cut-quality diminishes. CNC plasma cutting is used for precise applications, so it’s important that you maintain your plasma consumables to extend the life of your torch.
Use this checklist to determine whether or not you need to replace your CNC plasma consumables:
1. Get back to basics
When a computer won’t work, some wise guy always asks “Is it plugged in?” In the same way, if you’re having trouble achieving the perfect cut, start with the most basic elements in your torch: the consumables. Are you using the correct parts for the job, and are they assembled correctly? Make sure all of your CNC plasma consumables are seated correctly in the right places. Consult your operator’s manual, and follow its recommendations for maintenance.
2. Inspect your arc
A healthy arc is bright-white to light-blue in color. If it starts to turn orange or purple, it could be a sign of contaminants in your gas. A green arc is a red flag, indicating that you have burned through the tip on your electrode and are now burning (and melting) copper. If your arc turns green, replace your consumables immediately to avoid full torch failure.
3. Check your nozzle
Nozzles come in a variety of sizes to accommodate various types of cuts – the more focused the cut, the smaller the orifice. A visual inspection that reveals either an enlarged orifice, or one that has become oval vs. circular is a sure sign that the nozzle needs to be replaced. One thing that isn’t a factor here, though, is color. A discolored nozzle is not a sign of wear. See how your plasma tips can affect cut-quality.
4. Love your electrode
The electrode is a crucial piece in your CNC plasma consumables setup. Although it is largely made of copper, its conductive insert is made from hafnium. When the arc powers off/on, the hafnium becomes molten and adhere to the interior of the nozzle. Keep a close eye on the pit where the hafnium lives at the tip of the nozzle, which should never go deeper than 1mm as the hafnium degrades. If you work beyond that depth, the entire torch will soon fail. It’s a lot cheaper to replace the consumables vs. the entire torch.
5. Go for the silver
When you’re cutting steel, one of the most efficient materials used in manufacturing plasma electrodes is a silver insert. Silver conducts both heat and electricity well. When used near the hafnium tip, silver provides much-needed additional cooling and heat-protection. If you want to extend the life of your torch tip, upgrade to a silver electrode.