Tag Archives: Restoration
Plasma cutters cut so easily they seem like magic; even their name sound like something from a science fiction story. But they are real, and in the past 15 years the prices have come down to the point that nearly every shop has one, from the hard working professionals to the weekend warriors. In order to keep your plasma cutter working like a high tech X-acto knife, and not a rusty hatchet, you need to periodically replace the consumables to keep the arc consistent and the air focused.
What Are Consumables?
When talking about plasma cutter consumables people usually mean just 2 parts: the nozzle and the electrode. But there are other parts that may need replacing too like the diffusor and outer nozzle cover. Typically it’s the nozzle losing its focused jet of plasma, or the electrode producing weak spark that signals it’s time for a tune up.
Why are they consumed?
Plasma cutters can slice through thick hunks of metal like a hot knife going through butter, no joke. The plasma (super-heated, electrically charged air) which gives these tools their name is at a temperature of about 10,000° Fahrenheit, and moves at thousands of feet per second. The flow of air and electricity through the nozzle causes erosion the same way water does when running down stream. Sure the erosion is on the atomic level, but electricity flows at a much higher speed than running water, so with use it eventually wears out the precisely sized hole in the end of the nozzle.
The electrode does not have plasma running through it. The air, not yet charged or heated, swirls around it as it goes through the torch. The electrode needs this airflow for cooling so it doesn’t start to melt with all the heat coming off the end of it, where the plasma is formed. Just like the electrodes in a spark plug, there is a highly conductive core, surrounded by a lesser metal like copper. High voltage by itself will cause the erosion of the center of the electrode. Let it go too long and your torch will lose a great deal of its cutting ability, as the copper produces a lower voltage arc, and less hot plasma.
The outer nozzle, and diffusor don’t really wear the way the other 2 parts do, but it is a good idea to replace them occasionally too. A worn or cracked diffusor can cause the electrode or nozzle to run hot and wear out faster. The outer nozzle can be damaged by dropping the torch, or metal blowback into it, disrupting the air or plasma out of the gun. These parts should be replaced every ten times you replace the electrode and nozzle, even if they look okay.
Luckily, like many periodic maintenance projects, replacing plasma cutter consumables is a simple, quick and easy job on most machines. Once you’ve done it a few times it should only take a few minutes, provided you have the replacements handy already.
- Make sure the machine is off, maybe even unplugged. These machines can deliver more than 300v through you if they are on, so safety first.
- Unscrew the outer cover of the nozzle. The nozzle, diffusor and electrode should drop right out.
- Place the new parts in the torch and screw the outer nozzle back on, and you are done.
The 2 biggest things that cause quicker consumption of consumables are contamination in the air lines, and overheating the torch. Always run a quality oil/water separator on your line when using a plasma cutter, and be sure to drain the compressor tank periodically. Disposable in-line air dryers work well too, as added protection.
When cutting with your torch, working too slowly will expose the consumables to more heat, and cause them to wear out faster. Though move too quickly with your cut on thicker materials and the result will be lower quality, rough, slaggy cuts. Also make sure you are feeding the torch with enough air flow. Not only does the air provide the plasma, and the shielding/focusing, it also has to cool the electrode and the nozzle.
So in conclusion, like many other tools that make your life easier, plasma cutters require periodic maintenance. Most hand held plasma cutter torches make it easy; just a few minutes of down time are needed to do the job. The difference between a freshly tuned up torch and one with a worn nozzle and electrode can be as dramatic as being able to cut through inch thick steel, or having a hard time with 5/8”.
Consumable are not expensive either, as they are meant to be consumed. Eastwood carries all you should ever need if you bought one of our plasma cutters. A kit with 5 nozzles and 5 electrodes, plus a diffusor and an external nozzle is less than $50. The number of clean precise cuts you get, and the time you save with a well cutting machine are worth the price.
Check out the Eastwood Blog and How-To Center for more Tips and Tricks to help you with all your automotive projects. If you have a recommendation for future articles or have a project you want explained don't hesitate to leave a comment.
Just like paint, you can create custom powder coating finishes by adding metal flakes directly into the powder . Unlike paint powders will not accept pearl additives because pearls cannot withstand the high temperatures that powder requires to cure. With that said, creating custom powders is a game of trial and error because different powders have slightly different properties and accept flakes differently. Also each metallic flake will act differently at 400ºF so the following is not a strict formula for mixing flake to powder, more of a guideline of the entire process.
After painting the valve covers on my truck with High Temp Chevy Orange Paint, I noticed that after time they began to fade and in some spots start to peel up. I'll admit that they could have been prepped better the first time but now I get to re-finish them with a custom color unlike any other.
As you'll see above, the bottom valve cover is fully prepped and cleaned, while the top one has only been thorough the blaster.
Powder can be a very stubborn material to work with because the part being coated must be super clean in order to create the best finish. Don't let this steer you away, compared to paint, cured powder will resist temperatures up to 250ºF and all types of chemicals including DOT 3 brake fluid. Powder is great for almost any metal part on a vehicle that will be exposed to the elements or will see heavy traffic. In the interest of saving time I am not going to go into detail about how to properly prep the parts, for this info refer to one of our earlier articles How to Prep Metal For Powder Coating.
Different from paint, two different colored powders cannot be mixed to create a new uniform color. What you'll end up with is a "salt and pepper" effect where you will see both colors individually. If thats the finish you are looking for it is a perfectly functional option but don't expect a new color like you would with paint. On the other hand powder will accept some metallic additives but there is not a clear ratio of how much to add because every powder and metallic are different and will not react the same way. If you decide that you want to venture down the road of adding metallic to powder there are a few guidelines to follow. Darker powders will almost always show metallics the best compared to lighter colors. Additionally translucent powders will show metallics the best because the orientations of the flake does not matter because you will be able to see it through the powder.
For these valve covers I decided I wanted to go with a twist on the classic Chevy Orange Powder by incorporating Eastwood Alsip Orange Super Flake into the powder. Not knowing how the two would mix, I decided to test my mixture on a few test pieces to ensure it had the look I wanted.
The first test piece had way too much flake in it and it ended up looking and feeling like sand paper, the exact opposite of the smooth glossy finish I wanted. Throughout this project I used the Eastwood Dual Voltage Powder Gun on the II setting.
For the next test piece I decided to dial back on the flake in hopes of getting a smooth finish while still being able to see the flake. As you can see the metallic effect is muted and very subtle but the surface is smooth just like I wanted. Below you will see the distribution of the flake in the powder, it does not look like there is much but as you will see it really shows through.
Coating the Valve Covers
Before coating the valve covers I needed to outgas them first, which in simple terms means cooking off any contaminants that may still be on the surface. To outgas, I heated the part up to 410ºF, slightly above the curing temp just in case there were any contaminants that would not bake off at 400ºF.
I applied this mixture to the valve covers and cured them at 400ºF for 20 minutes. When adding flakes to powder you have to watch the time carefully because the flakes may change slightly if cured for too long.
The coverage was great and they turned out looking really nice because you could see the metallic, but only if you really looked for it. I had a hard time getting it to even show up in a picture. Don't get me wrong, they looked great but to get that WOW! look when I open the hood, they still needed a little more sparkle.
Mixing Into Clear
Deciding between just applying clear or to mix flake into the clear was a tough choice, since each powder reacts differently I decided to use my second test piece to see how the flake/clear will end up looking and go from there. I used Eastwood Super Gloss Clear Powder at 1/3 of an 8oz container to 1 tsp. of the same Alsip Orange Flake, Above you can see the flake distributed in the clear.
The results were amazing and exactly what I wanted, this meant the valve covers were going back in the oven to be hot flocked. The clear recommends a cure temp of 375ºF, but with the added flake I decided to preheat and cure at 385ºF to make up for the added flake. I'm not sure if this was needed but it didn't affect the end result.
They looked great after the first coat but I decided that I would hot flock them again and apply one more, on the first pass I did not attach the grounding cable causing me to miss some spots. One great attribute of the clear powder is that you can layer it as many times as you would like, until you get the look you want. If you want to do multiple coats of clear make sure you use PRE to remove any contaminants that may be present.
The final result was spectacular it almost looks like it should be its own color. In good light the metallic stands out beautifully, and its great knowing that this is a one off color that no one else has. Eastwood offers such a variety of powders an additives that the possibilities are only limited by your imagination. Just remember to measure out the ratios or each component in case you need to make more later on.
Check out the Eastwood Blog and How-To Center for more How-To's, Tips and Tricks to help you with all your automotive projects. If you have a recommendation for future articles or have a project you want explained don't hesitate to leave a comment.
- James R/EW
TIG welding is the Tungsten. In fact that is what the first letter in TIG stands for: Tungsten Inert Gas. TIG uses an inert gas to shield the weld (typically Argon), a filler rod of a metal that matches what you are welding, and an electrode made of Tungsten that focuses and directs the arc. All TIG electrodes are more than 95% Tungsten, which is a rare metal used because it is hard and has one of the highest melting points of any metal. There are at least 5 distinct types of “Tungstens”, as most people call them, typically color coated based on how much of what other elements have been added.