Since their founding in 1929, Miller Electrics has gained a reputation for producing some of the best welders in the welding industry. Their product line includes all common types of welders from TIG to stick, and these machines are praised by tradesmen for their robustness and quality welds.
This article covers three of the top-tier Millers generator welders, and illustrates how Red-D-Arc welding gear and Miller’s generator welders can equip you with the best welding gear that you need for your next project!
Unraveling the Generator Welder
Also known as an engine driven welder, a generator welder combines a gasoline, diesel, or propane engine with an electrical generator. It is a powerful combination that easily provides all of the energy you need for demanding welding tasks and can even power auxiliary tools like fans, pumps, and air compressors. Depending on the model, generator welders can be used with various welding techniques, including TIG, stick, MIG, and flux-cored.
The portability of generator welders makes them a favorite among skilled trades workers. They can be easily transported to any job site, eliminating the need for external plugs and making them ideal for outdoor operations. And they also provide a reliable power source for your industrial tools!
An Introduction to the Generator Welder
Miller Big Blue Air Pak (Deluxe) CC/CV AC/DC 20 kW
The Miller Big Blue Air Pak (Deluxe) CC/CV AC/DC 20 kW is a super versatile welding machine that packs a serious punch with its impressive output of up to 20,000 watts. This bad boy can handle all sorts of welding processes, from aluminum to plasma. But wait, there’s more! It’s not just a welding machine, it’s also a generator and air compressor all rolled into one. Talk about a handy-dandy tool for all you skilled trades workers in the welding industry!
And here’s the cherry on top: this machine is built to last. It’s designed to withstand any kind of weather, so you can take it with you wherever the job takes you. Plus, it’s got some user-friendly maintenance features that make it even more reliable. All in all, the Miller Big Blue Air Pak (Deluxe) CC/CV AC/DC 20 kW is the real deal, giving you power, versatility, and durability all in one sweet package.
Product specifications for the Miller Big Blue Air Pak:
- Engine: Deutz, BF4M 2011 Diesel TD2011L04w
- Fuel: Diesel
- Rated Output:
- Stick 600 A, 44 V, 26.4 kW, 40% Duty Cycle
- Stick 550 A, 42 V, 23.1 kW, 60% Duty Cycle
- MIG/FCAW 500 A, 40 V, 20 kW, 100% Duty Cycle
- AC TIG 400 A, 26 V, 10.4 kW, 100% Duty Cycle*
- Weld Output Range:
- DC Stick 45–750 A MIG/FCAW 14–40 V
- DC TIG 20–450 A AC 20–575 A
- Battery Charge 12/24 V, 50–750 A
- Generator Power: 20,000 watts peak, 12,000 watts continuous
- Processes: Stick (SMAW), MIG (GMAW), Flux Cored (FCAW), Submerged Arc (SAW), AC TIG (GTAW), DC TIG (GTAW)
Thanks to its impressive power output and versatile capabilities, the Miller Big Blue Air Pak shines as a reliable choice for professionals of any skill level.
Miller Trailblazer 325 AMP Gas Engine Welder
The Miller Trailblazer 325 is packed with awesome features that make it a radically top-notch welding machine. Not only does it deliver superior arc performance, but it also automatically adjusts its speed to ensure the perfect weld every time. Plus, it’s designed to optimize fuel usage, so you can work more efficiently. And the best part? It’s surprisingly quiet, making it the ideal choice for those quieter job sites.
Product specifications for the Miller Trailblazer 325 AMP Gas Engine Welder:
- Engine: Kohler CH730
- Fuel: Gasoline
- Rated Output**:** 325 A at 28 V, 100% duty cycle
- Weld Output Range:
- CC/DC Stick/TIG: 10 – 325 A
- CV/DC MIG/FCAW: 10 – 35 V
- Generator Power: 12,000 watts peak, 10,500 watts continuous
- Processes: Stick (SMAW), TIG (GTAW), Pulsed TIG, MIG (GMAW), Air Carbon Arc Cutting, Flux-Cored (FCAW)
No matter what kind of job you’re tackling, the Miller Trailblazer 325 is up for the challenge. Its durable construction and multi-process capabilities allow for precise welds and give you the confidence to tackle any welding project that comes your way!
Miller Bobcat 250 – 250 AMP Gas Engine Welder
Now, let’s talk about the Miller Bobcat 250 – a real powerhouse in a compact package. This welder is perfect for maintenance, construction, and even power generation tasks. It’s tough and rugged, and that makes it a great choice for stick and flux-cored welding. But don’t let its size fool you, because it’s also versatile enough to handle other welding processes too. With the Miller Bobcat 250, you can expect excellent performance and reliability, making all your welding projects a breeze.
Product specifications for the Miller Bobcat 250 – 250 AMP Gas Engine Welder:
- Engine: Kohler CH730
- Fuel: Gasoline
- Rated Output:
- CC/AC Stick/TIG: 250A/25V/60%, 225A/25V/100%
- CC/DC Stick/TIG: 250A/25V/100%
- CV/DC MIG/FCAW: 275A/25V/60%, 250A/28V/100%
- Weld Output Range:
- CC/AC Stick/TIG: 40 – 250 A
- CC/DC Stick/TIG: 40 – 250 A
- CV/DC MIG/FCAW: 17 – 28 V
- Generator Power: 11,000 watts peak, 9,500 watts continuous
- Processes: Stick (SMAW), TIG (GTAW), MIG (GMAW), Air Carbon Arc Cutting, Flux-Cored (FCAW)
Professionals in the welding industry love the Miller Bobcat for its user-friendly design and its ability to produce a reliable arc, all at an affordable price.
Welding Equipment Rentals
Looking to rent welding equipment? Look no further than Millers generator welders. These machines are known for their versatility, power, and reliability. They’re the go-to choice for professionals who want the best. So why not step up your welding game and see what all the fuss is about? Rent a Miller generator welder today and experience welding like never before.
Plasma cutting produces clean and accurate cuts when set correctly. But certain maladjustments and errors can cause excessive dross and slag to form on the cut edge, which impairs your productivity. Nobody wants to clean the dross, especially not from a large batch of cut pieces.
Whether you rent plasma cutters or buy them, you can’t experience all benefits of plasma cutting unless you minimize or eliminate dross. So, let’s discuss some effective ways to prevent and remove dross on your plasma cuts.
Understanding Dross And Slag in Plasma Cutting
Dross, sometimes called slag, forms underneath or on top of the cut edge when plasma cutting. While eliminating simple and common errors leading to dross formation usually provides a clean cut, it’s not uncommon that even experienced plasma cutter operators get dross buildup.
What is Dross/Slag?
Dross is a molten metal that solidifies at the edge because the air/gas pressure didn’t blow it away. As you plasma cut, the compressed air/gas blows away the molten metal from the cut line, but there are many reasons why a part of the blown metal can adhere to the cut edge.
Sometimes you’ll see people refer to dross as slag. But, “dross” is the most accurate term since slag is usually associated with the protective residue when performing MMA or FCAW welding processes. Still, dross can resemble slag appearance, so these terms can be used interchangeably to define the re-solidified metal at the plasma cut line.
Why Are They a Problem in Plasma Cutting?
If you run a fabrication shop, you know how bad any bottlenecks in production can get. No one wants to miss deadlines or hold back on taking more jobs. But, plasma cutting a large batch, like 500 machinery parts, will take significantly longer if every part needs dross removal on some or all edges.
To make things worse, removing certain kinds of hardened dross requires using an angle grinder, which can leave a relatively large visually-altered area due to the abrasiveness of the grinding stone. In addition, stainless steel or other sensitive metals may experience discoloration, warping, and loss of mechanical properties during post-cutting dross removal.
Some metalworking shops may not have enough workforce to manually remove the dross from a large batch of cut parts. A small shop could take on a big job and struggle to manually clean the edges if there is a significant amount of hardened dross.
Preventing Dross and Slag Formation
The best cure for dross is prevention. If you set up your plasma cutting parameters correctly, you can save significant labor hours on dross removal and achieve clean cuts.
Choosing the Right Plasma Cutting Parameters
“It’s vital to synchronize your plasma cutting speed with the amperage output for the cut material type and thickness.”
It’s vital to synchronize your plasma cutting speed with the amperage output for the cut material type and thickness. Every cutting system has detailed settings in the manual. You can rent plasma cutters from Red-D-Arc, and they all come with instructions for setting up the cutting parameters. Even portable plasma cutters, like the Hypertherm Viper 45, include details on how to set them up for the cut thickness and material.
But, even if you do set the plasma cutting system correctly, you can sometimes get some dross on the cut edges. Slight differences in material thickness and alloy can cause this, and the simple solution is to fine-tune the settings to find the sweet spot.
Generally, using too high of a cutting speed or low amperage causes dross to accumulate on the bottom edge as hard globs of metal, due to the arc lagging behind the torch. These metal globes are challenging to remove and require extensive grinding or machining to get a clean edge. Sometimes excessive travel speed can also cause dross to form on the top edge of the piece depending on the torch standoff distance, material type, and cut thickness.
On the other hand, too low of a cutting speed or too high amperage output produces very thick dross at the bottom of the cut. That’s because a slow-moving arc focuses more energy than necessary per inch of cut metal. So, the arc stays for too long in the area that’s already been pierced. As a result, the arc widens and starts “eating” the walls of the cut because it is looking for more electrically conductive metal; if it can’t find it in front, since it’s moving slowly, it will find it left and right. But, eventually, the kerf widens so much that the air/gas pressure can’t physically force the molten metal to fly off from the cut, resulting in thick dross formation.
Maintaining Proper Torch Height and Standoff Distance
If the torch distance from the cut piece is too low, you’ll get a similar dross formation effect as cutting with low speed. Reducing the standoff distance causes too much energy buildup.
Cutting with too high a standoff distance, or torch height, can cause the opposite effect. Too high a torch distance reduces your arc power, causing a similar effect as when cutting too quickly ‒ hard dross accumulation.
Using High-Quality Consumables
Using high-quality consumables, like the SYNC consumables available with SYNC Hypertherm plasma cutters, will help you make clean cuts. But, regardless of the used plasma cutting consumables, they need to be in good condition to make clean edges without dross.
Nozzles showing signs of wear, like orifice turning elliptical, should be replaced. The poor consumable condition can contribute to dross accumulation.
Effective Techniques and Solutions for Dross and Slag Removal
You can employ several methods to remove the dross. But, choosing the dross removal technique depends on the dross hardness, material type, and time/labor constraints.
Mechanical Methods
Mechanical slag/dross grinders can remove the dross from the cut parts by rotating tiny pins opposite to the metal being fed into the machine. As a result, pins hit and break off any dross accumulated on the metal’s surface.
Using Chipping Hammers or Scrapers
Chipping hammers, scrapers, and chisels work well for the dross that hasn’t hardened and when working with low-volume part batches. Even if the slag breaks off just by scraping it off with a putty knife, it can be time-consuming to clean many parts.
Grinding and Sanding Techniques
One of the most effective ways to remove medium-thickness slag is the angle grinder with a flap disc. It’s fast, effective, and won’t gouge out much of the parent material. But, if the slag is thick and hard, the angle grinder with a grinding disc will get the job done. However, grinding with a disc can damage the face of the cut part.
If you are dealing with light dross, you can use an angle grinder with a wire brush wheel to remove it. While it’s significantly faster than using a chipping hammer for large batches, grinding is a safety hazard. Wearing eye and body protection is non-negotiable when using an angle grinder.
You can also use a sanding belt to grind off dross of any size and strength. But, they are also better suited for dross removal on non-ferrous materials like aluminum. You can’t use regular grinding discs for aluminum because it’s too soft for them. Grinding discs can load on aluminum, posing a safety hazard and significantly reducing efficiency. But, sanding belts expand the sandpaper’s narrow grooves, making them less likely to clog up on aluminum.
Chemical Agents
You can use anti-spatter sprays to prevent dross from adhering to the cut edge to an extent. The degree of success will depend on the chemical composition and the brand’s quality.
Best Practices for Dross and Slag Management
Now that we’ve covered how to prevent dross from forming and how to remove it if it does develop, let’s discuss some practices for dross and slag management in your shop.
Regular Cleaning and Maintenance of Plasma Cutting Equipment
“Letting the metal dust pile inside the power source may impede the cut quality.”
To reduce the dross accumulation, your plasma cutting equipment needs to be in tip-top shape. If the consumables are regularly replaced, your cuts are less likely to have dross. In addition, a clean and dust-free plasma cutting power source will deliver accurate and consistent amperage output. So, it’s important to conduct regular maintenance of your equipment. Letting the metal dust pile inside the power source may impede the cut quality. The same goes for the CNC table and other equipment you rely on to behave according to the set cut speed, amperage, torch distance, and cut path.
Proper Disposal of Dross and Slag
Regardless of how small pieces of metal are produced when chipping away the dross, they still pose a safety hazard. Workers can experience cuts and eye injury from dross removal and subsequent handling.
Workers must wear full personal protective equipment (PPE), like work gloves, pants, jackets, and eye protection that meets ANSI Z87.1 standards.
Collected dross should be sent to recycling, along with other scrap metal from a fabrication shop. While fabrication shops today produce far less scrap than in the past, some metal parts, like the dross, are pure waste that can’t be used again without recycling.
Conclusion
Using the correct settings for amperage output and travel speed with high-quality consumables, will significantly reduce the amount of produced dross. If you still get some dross on the cut line, change the cut parameters incrementally. Sometimes the gas choice, material type, thickness, and other variables require slightly different parameters than described in the user manual.
Plasma cutting is a fast, reliable, cost-effective, and downright simple way to slice electrically-conductive metals. But, Hypertherm SYNC Technology makes plasma cutting setup far easier and more efficient.
Learn how the Hypertherm’s next-generation smart plasma can improve your workflow, make cutting and gouging metal easier and faster, and how you can track the usage of the machine.
Why Choose a Plasma Cutter To Cut Metal?
While plasma cutting has a few safety considerations, like protecting from electrocution, eye and physical injuries, toxic fumes, and fire hazards, it’s one of the most accessible manual and automated metal-cutting methods.
Plasma cutters are lightweight and portable thanks to their IGBT-inverter cores. Therefore, cutting metals on-site is straightforward. In addition, it’s often not necessary to make any metal preparation, especially if the plasma cutter supports a pilot arc. You can cut painted, dirty, oily, or rusty metals because the pilot arc doesn’t rely on the contact between the nozzle and the workpiece to establish an arc.
You’ll achieve the best results with conductive metals. So, you can easily cut plain carbon steel. But the plasma cutting process also works with stainless steel, aluminum, brass, copper, and other conductive metals that cannot be cut with oxy-acetylene.
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