Plasma cutters are amazing tools for cutting through materials that are electrically conductive (like copper, brass, and aluminum). They use a compressed-air driven jet of hot plasma to accomplish cutting. Plasma cutters produce cleaner work than grinding, but are more expensive and require a bit more practice to use proficiently than grinders. Understanding how plasma cutters work and what to look for in a model that will meet your needs can help make it easier for you to invest in the right cutter.
Many plasma cutters require standard 15-amp, 120-volt outlets. More powerful models might need 20 amps and 120 volts or even 50 or more amps and 240 volts. The nature of your intended projects will determine how powerful your cutter needs to be. As a rule, 15 to 25 amps will work just fine for cutting metals 1/4 inch or less thick. Cuts up to 1/2 inch usually need 40 amps. You’ll probably need at least 80 amps if you’ll be making cuts 1 inch or thicker.
Once you determine how powerful your new cutter needs to be, it’s time to decide what duty cycle you want. Duty cycles are typically represented as a percentage that indicates what percent of a 10-minute period the unit can run before needing some cool-down time. For instance, a duty cycle of 50% means that the cutter can run for 5 minutes before needing to cool off. Duty cycles will be based on power settings, so make sure you look at duty cycles in relation to your intended use.
As mentioned above, compressed air is necessary to use your plasma cutter. If you don’t have a shop or work area that’s equipped with an air source, you’ll need to find one. Many plasma cutter manufacturers assume that you already have an air source, but some models do come with their own compressor. Make sure you know which type you’ll need. Since clean and strong airflow is critical to the cleanest work, you might want to consider a filtration system. A filter can eliminate stray dust particles, which will keep your work cleaner and help keep your cutter’s inner workings cleaner longer. This will help your consumables (we’ll discuss them below) last longer, which can save you money. A filter system that also includes a desiccant component will remove any moisture from your air stream, which is another way to get the cleanest work and the most life out of your consumables. Filter systems, especially those with desiccants, can be pricey, so you’ll need to decide whether the cleaner work and longer-lasting consumables make adding a filter a worthwhile investment for you.
Consumables represent an ongoing expensive for those who use plasma cutters. These are parts that are essential to the cutter’s operation but will, over time, wear out and need replacing. How often they need to be replaced will depend on use and initial quality. Many plasma cutters that cost less to purchase actually have consumables that don’t last very long and are relatively expensive to replace, making them less cost effective than some higher-cost cutters that feature longer-lasting and lower-priced consumables. When narrowing down your search, it would be very wise to spend some time researching consumable life expectancy and replacement cost (as well as ease of obtaining replacements) before making a final decision. There are 5 different consumables involved:
- The electrode: This is what carries the current from the cutter’s torch to the plate.
- The nozzle: This part funnels the gas flow and focuses your arc.
- The swirl ring: This ring is responsible for channeling the gas.
- The retaining cap: The consumable stack is held together by this cap.
- The shield: This part is critical to protecting the other consumables from molten metal and sparks.
Visit best plasma cutter models for buying info and reviews (including pros and cons) of several models designed for different types of users with different budgets. Understanding what makes a plasma cutter right for your needs and your budget, in the short and long terms, is the best way to ensure you’ll make an investment you won’t regret.