It's a well-known fact that having the correct tools makes any job easier, and in turn, a well-equipped shop makes a classic pickup project a heck of a lot more enjoyable and successful. In my case, and I'm assuming many of yours as well, the equipping of a home shop is one that's achieved over the course of time. Initially starting with a satisfactory selection of basic handtools like socket sets, combination wrench sets, screwdrivers, pliers, clamps of various types, an ever-handy array of hammers and a prybar or two.

From that point comes assorted power tools, both handheld examples such as grinders, drills, saws, etc., and fixed power tools like air compressors, bench grinders, drill presses, and welding equipment (arc, MIG, and/or TIG). In my case, handheld power tools, certain specialty tools, and fixed or bench-top tools are added (in a seemingly endless cycle) to my arsenal in an as-needed (or sometimes as wanted) manner.

Over the years I've noticed that aside from my handtools, required in nearly every facet of mechanical work, there are a few power tools that see much more use than others. In my case, it's been my compressor, my MIG, my stationary belt sander, and either my cut-off wheel equipped die grinder or my 4½-inch electric grinder also fitted with a cut-off wheel.

The last two (along with the occasional Sawzall situation) have been indispensable for cutting and fabricating nearly any and all my metalworking chores. That is until fairly recently when I finally acquired what has now become another one of my most often used power tools – a plasma cutter. And let me tell you, I thought I had my cutting chores deftly handled by the use of my die grinder and electric grinder – that was until I used my plasma cutter for the first time. From that point on it has become my go-to tool for metal cutting of nearly every kind.

For those unfamiliar with plasma cutters, or those who might be considering the purchase of one in the future, lemme try to give you a bit of expressly non-professional info, a touch of personal opinion, in this regard.

Plasma Cutters and How They Work
Nowadays, plasma cutters come in all sizes. There are large industrial plasma cutters that use robotics to make precise cuts. There are also compact units that are perfect for use in autobody shops, small manufacturing concerns, and home shops/garages like yours and mine. Regardless of size, all plasma cutters function on the same principle and are constructed around the same basic design.

Plasma cutters work by sending a pressurized gas, such as nitrogen, argon, compressed air, or oxygen, through a small-diameter passage in the cutter handle. In the center of this passage there is a negatively charged electrode. When electrical power is supplied to the negative electrode (the trigger pressed), and the tip of the nozzle is lowered to the metal to be cut, a circuit is completed and a powerful spark is generated between the electrode and the metal. As the inert gas blows through the passage, the spark super-heats the gas until it reaches the fourth state of matter (The four states being in order: solid, liquid, gas, and plasma).

This reaction creates a stream of directed plasma (super-heated gas), at approximately 30,000-degrees Fahrenheit and moving at about 20,000 feet-per-second, which transforms metal to molten slag, while the shielding gas blows the slag out of the way. The plasma itself conducts the electrical current, and the cycle of creating the arc is continuous as long as power is supplied to the electrode and the plasma stays in contact with the metal that's being cut. In order to ensure this contact, to protect the cut from oxidation, and to regulate the plasma, the cutter nozzle has a second set of passages that provide a constant flow of shielding gas around the cutting area. The pressure of this gas flow effectively controls the radius of the plasma beam.

Plasma cutting can be used on any type of conductive metal, though in our restoration/fabrication cases mild steel, aluminum, and stainless are the most common metals we run across. With mild steel you'll experience faster cuts in thicker objects than you will with alloys. Plasma cutting produces enough energy to melt the metal and also creates the momentum needed to blow the melted slag away. Because of this, plasma cutting can cut non-ferrous materials, requires a lower skill level, and offers faster travel speeds versus sawing or the use of oxyacetylene torches. Plus, it doesn't require the use of flammable or explosive gasses and therefore is safer to operate.

What to Look for When Considering a Plasma Cutter
One of the first factors you need to determine is the thickness of metal most frequently cut. Plasma cutters are most often rated by their cutting ability and amperage. Consequently, if say ¼-inch-thick material is the most common maximum thickness of what you'll normally be cutting, you might consider a machine in the lower amperage range.

If you think you'll possibly be cutting metal that is ½-inch thick, look for a higher-amperage machine. Even though a smaller machine may be able to cut through a given thickness of metal, it may not produce a quality cut. Instead, you may get a sever cut, which barely makes it through the plate and leaves behind ragged edges and lumps of slag. Every unit has an optimal range of thickness – make sure it matches up with what you need. In general, a ¼-inch-rated machine has approximately 25 amps of output, a ½-inch-rated machine has a 50-60-amp output, while a 1-inch-rated machine has 80 amps output.

The plasma cutter that I've chosen for my shop is the Versa-Cut 60 from The Eastwood Company. In my opinion, the Versa-Cut was, dollar for dollar, the best all-around choice I could have made for a machine that's capable of making quick, clean cuts in steel, stainless, or aluminum as thin as 24-gauge or as thick as a whopping 7⁄8 inch. The VC 60 is a heck of a lot faster than mechanical cutting and makes curved and intricate cuts much easier and more precise than any saw or cut-off wheel can. Another of the things that make the VC 60 perfect for our restoration needs is its built-in pilot arc system, which allows for easy instant arc striking when cutting less than pristine and/or rusty metal. It is also equipped with an internal moisture separator that helps to ensure clean, dry air at the torch for clean consistent cutting.

Eastwood's VC 60 is a 220-volt unit with a compressed air requirement of 5 to 7 cfm at 20 to 60 psi and has an output range of 20 to 60 amps with an output voltage of 104 volts and a 60-percent duty cycle at 60 amps. For those unfamiliar, duty cycle refers to the amount of cutting (or welding) a machine can do in a specific amount of time. Most often that amount of time is measured in 10-minute blocks with the duty cycle being a percentage of that time frame. In other words, cutting at 60 amps with a 60-percent duty cycle, you can cut for six minutes out of 10 with a four-minute cooling-off period. Personally, I can't see any situation where I'd need six full minutes of continuous cutting in a classic truck restoration situation, but it is satisfying to know that I'm able to accomplish nearly any chore without fear of running up against a duty cycle cut-off.

Tips For Successful Plasma Cutting

Set-Up Procedures
Before you start, check for the following items: Make sure you use a clean air supply without water or oil contamination. Use the correct air pressure. It can be checked by looking at the gauges on the unit. Make sure the nozzle and electrode are correctly in place. And finally, make sure the ground connection is clamped to a clean portion of the work.

Safety Gear
Basic safety practices should always be observed. Read the instruction manual thoroughly before using the machine. Wear long sleeves and gloves while cutting since molten metal is generated during the cutting process. Eye protection such as dark goggles or a welding shield is required to protect your eyes from the cutting arc. Typically shade #7 to #9 lenses are acceptable. Finally, follow all safety tips and guidelines that are detailed in the Eastwood instruction manual.

Piercing the Work
Many beginners try to pierce the metal by pointing the nozzle straight down perpendicular (90 degrees) to the work. Not good, doing so will result in molten metal being blown back up into the torch and possibly your face as well. A better method is to approach the metal at a slight angle (60 degrees) and then rotate the torch to 90 degrees. This way, the molten metal is blown away from the torch.

Don't Touch the Nozzle to the Work piece
Do your best to not touch the nozzle to the work when using current levels of 45 amps or more. Doing so will drastically reduce the nozzle life as the cutting will double arc through the nozzle. Double arcing can also occur if a metal template is used. In this case, the user drags the nozzle along the template. The result is the same as dragging the nozzle on the work – prematurely worn nozzles.

Travel at the Right Speed
When moving the torch at the correct cutting speed, the molten metal spray will blow out the bottom of the plate at a 15- to 20-degree angle. If you are moving too slowly, you will create slow-speed dross, which is an accumulation of molten metal (slag deposits) on the bottom edge of the cut. When moving too fast, high-speed dross is created since you are not allowing time for the arc to completely go through the metal. Traveling too fast or too slow will create a low-quality cut. Typically, low-speed dross can be distinguished from high-speed dross by ease of removal. For example, low-speed dross can be removed by hand, whereas high-speed dross typically requires grinding.

Begin at Maximum Current
When setting the current, set it to the maximum output of the machine, and then dial it down as needed. More power is usually better, except when doing precision cutting or when you need to keep a very narrow cut.

Minimize Pilot Arc Time
Because of the wear it creates on the consumables; try to minimize the amount of time spent in pilot arc mode. To do this, get ready by the edge of the work before starting the arc so you can get right to cutting.

Maintain a Constant Work Distance
For the best results, do your best to maintain a steady 3⁄16 to 1⁄8-inch distance between the nozzle and the work.

Travel in the Direction That Will Give You the Best Finished Work
For example, if you're making a circular cut and plan to keep the round piece as your finished work, move in a clockwise direction. If you plan to keep the piece from which the circle was cut, move in a counterclockwise direction. As you push the torch away from you, the better cut will appear on the metal that is on the right-hand side, since it will tend to have a better, squarer edge.

End With a Push On Thick Material
One trick used on thicker material is to give a slight push as you cut through the last section of material. This increase in the push angle at the finish will cut through the bottom first and get rid of the bottom corner that is usually left at the end of thick plate. Never finish a cut by using the torch to hammer away the last corner of the work.

Hopefully I've offered up some useful information on what I think is one the best plasma cutters around (the Eastwood Versa-Cut 60) as well as a bit of background on how plasma cutters operate and a few useful tips too. I know mine has saved me tons of time and effort so far and I'm sure it'll be doing the same for a long, long while.

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