Welding Basics

Welding is something all race teams do on a regular basis, whether it’s the NASCAR Winston Cup Series or the thousands of Friday- and Saturday-night racers across the country. However, just because welding is a common practice, that doesn’t mean everyone is doing it correctly.

“I see a lot of people who are welding without the proper expertise of what they’re doing,” says Joe Kolasa, a welding instructor with Lincoln Electric. “They need to have more training because their finished product just doesn’t look good. That just gives you an opportunity to have a defect in the weld.”

In an effort to increase the education of welders, Lincoln Electric offers race teams a welding school where they can go to learn about new industry trends. Much like drivers themselves, some of the veteran welders can be somewhat resistant to change something they’ve been doing all their lives.

Shane Love, head welder at Joe Gibbs Racing, is aware of the need to keep up with new technologies. With this in mind, he and 16 other team members attended the five-day class Lincoln offers.

“The reason I did that is because we have guys who have been welding all their lives, but they learned everything they know from doing it in the garages coming up through the Friday- and Saturday-night ranks,” Love says. “There is a lot that goes into welding and why things need to be done in the proper ways. “The class taught us about the fundamentals of metallurgy and what a weld actually does to the material that’s being welded. Every single one of those guys came back from the school and told me they’d learned something, and that surprised me because there were some guys I thought didn’t need to go.”

Miller Welding is another key player in the stock car ranks with teams including Hendrick Motorsports, Dale Earnhardt Inc., Roush and Richard Childress Racing. According to Andy Weyenberg, motorsports marketing manager at Miller Welding, many different factors go into not only good welds, but also safe welds.

“Ninety-eight percent of the welding shops out there are not using adequate welder safety from a manufacturer’s standpoint,” Weyenberg says. When it comes to Stock Car Racing, nearly all the welding processes are the same, whether it’s a Late Model short track team in California or a Winston Cup team in the Carolinas.

Stock Car Racing asked the experts to provide advice on welding. They say the key to proper welding is good education, using the correct process, the proper equipment, knowing how to inspect the weld, and using the proper safety equipment.

Education

“The main thing a welder needs is an education,” Love says. “There are a lot of people who weld even though they don’t know what a good weld is supposed to look like. They will weld something either way too cold or way too hot. My advice would be for them to do some research on all the information that’s available. You can easily go to a community college and take a basic class in welding. That’s how I learned how to weld and they taught me a great deal.”

Love says there are many books on the market, too, that are descriptive on what a good and bad weld is supposed to look like. “If I was a non-welder, the first thing I would do is research on what a good weld is supposed to look like,” Love says. “It’s also important to practice what you’re learning for a little while and try to make the welds look like the ones in the pictures. If it doesn’t look like what the pictures show as a good weld, then they need to go back and do more research.

“It could be something as simple as the welding machine’s temperature isn’t set just right. You can spend two hours and learn the difference in appearance when it comes to a good and bad weld.”

Correct Process

As Love says, it’s critical to know what a good and bad weld is supposed to look like. But successful welding goes well beyond that. It’s also critical to know what kind of process is needed to make a correct weld.

For assembling stock cars, there are two main types of welding done—TIG and MIG—and both require different types of procedures to get the maximum strength out of a weld.

MIG stands for Metal Inert Gas, and is a faster type of welding. TIG is the abbreviation for Tungsten Inert Gas, which is a type of electric arc welding process used primarily for thin and non-ferrous metals such as aluminum, magnesium and stainless steels.

“The TIG welding process is like brazing with a torch, except that the heat source is an electric arc where the amperage can be adjusted,” Kolasa says.

“It’s almost like using the dimmer switch in the lighting of a house, because in TIG welding you want to be able to adjust the heat level through a remote control, most commonly a foot control that can be pressed down to get more heat, and letting the pedal up to get less heat. Once the molten puddle is established, filler rod is added manually with the opposite hand.”

Kolasa says one of the advantages of the TIG process is the heat level can be adjusted independent of how much filler metal is added. The operator now controls the correct level of heat in order to make a good weld.

“In MIG welding, a wire is continuously fed through a gun and a gas is fed simultaneously from a bottle to protect the arc,” Kolasa says. “When that wire comes out, you have a certain arc length you have to maintain. Actually, the wire hits the metal and shorts out, which creates heat and melts. So the wire is constantly melting across the arc, whereas in TIG welding you are melting the metal with a separate heat source and adding filler rod by hand.”

Weyenberg says that due to the time it takes to weld something major like a rollcage, the majority of teams choose the MIG process.

“If you were to TIG weld a chassis, it’s going to take two-and-a-half times the time to do it that way compared to MIG welded,” says Weyenberg. “If you look at a team like Hendrick Motorsports, they MIG weld their chassis together because that’s a production facility and they’re kicking cars out all the time. If they need a car, they can do that in a couple of hours whereas if they TIG weld it’s going to take them two days to do the same job.”

Right Equipment

Once the welder has a basic education of what he’s doing and has decided whether he wants to use the TIG or MIG process, the next step is figuring out if the equipment he’s using is capable of doing a quality weld. One of the most common mistakes race teams make is using welding equipment that is not up to the proper amperage or doesn’t allow the recommended voltage to reach the source.

“Welding is so dangerous, and Saturday-night racers are the worst because of the simple fact that they don’t know how it’s supposed to be done,” Love says. “Those guys just love to race, and God bless them because they love what they’re doing. It’s very important to use the right equipment for the certain type of work being done. A lot of guys will use a 110-volt welding machine when they need to be using one that’s 220 volts.”

An array of simple items can be easily overlooked, even something as simple as the extension cords hooked up to the welding machines.

“The extension cords can cause you to drop some of the power that’s needed to get a good weld,” Weyenberg says. “A lot of the teams I see aren’t using the right cord so they’re not getting the correct thickness of the conductor. You need to have the proper cords because these welding machines draw a lot of power. If you don’t use the proper cord, it can be like trying to jump-start your car with a lamp cord. A lot of people don’t realize they’re losing a lot of their power through their extension cords.”

Another important area not to be overlooked is making sure the welding machinery has enough amperage for the job that’s being done.

“Some teams fail to achieve proper fusion, which basically happens, for instance, when you take a little 110-volt welding machine and work on heavy things like shock mounts,” Kolasa says. “Some people feel they can do anything they want with one of the smaller machines that is intended for thin materials. If you were to use that machine when it comes to something like a shock mount, you might as well skip welding it and just stick some bubble gum there instead because it won’t work. It’s a misunderstanding of the welding process that comes from a lack of education.”

Weld Inspection

After the job is completed, it’s important to make a visual inspection of the weld to make sure it looks secure and safe.

“You want to make sure the material deposition and travel speed are matched to get adequate penetration,” Weyenberg says. “The toes of the weld need to be tied into the base metal so it doesn’t look like a cold-welded joint. During a crash, the tubing wants to tear away at the weld. If the toes of the weld aren’t tied in properly, the weld will crack. It’s the same thing as having a cavity in your tooth.

“When you’re looking at a weld bead, the bead itself is like using a caulking gun to string out a line of caulk. The toes would be the side of that caulk, not the start and not the end; it’s the two sides. It should be a smooth transition.

“There’s a very fine line between a good weld and a bad weld. It can be as simple as how you’re holding the gun when welding. Keeping your gun at the same angle in relationship to the tubes is very critical. If you stop and move your gun from a push angle to a pull angle, the weld bead changes.”

It’s also important to take note, however, that a visual inspection won’t always catch things such as contaminant materials in the weld that can pop up from not cleaning the base material properly.

“There’s a ton of different ways to bad weld, and it’s not always something you can catch visually,” Love says. “Take somebody who’s MIG welding for example. They might have the machine cranked up really hot and the weld looks all nice and flat, but if you look at the edge of the weld it’s undercut. You can see where the material is melted down and then the weld starts. If that area was to ever get hit or bent, that’s a perfect place for a crack to happen.”

Personal Protection

Since welding can be such a dangerous job, those involved in the work need to take safety precautions. This comes from what type of clothing they’re wearing all the way to the level of shade they use for eye protection.

“From my standpoint as a manufacturer, if I had to recommend what people should wear while welding, they’d be in leather chaps and have leather from head to toe,” Weyenberg says. “The most important thing you need is a welding helmet. A lot of guys will skip that because they think they can just shield their eyes with something to block those rays, especially when they’re inside the car welding. Another problem I see is people who will go out and buy a helmet that doesn’t provide the right level of eye protection. Welding without a helmet on is a big-time no-no. There is enough quality protection out there to keep welders safe.

“There are even automatic shading lenses that are great because you can keep your helmet on in a down position to see where the weld is going to be started. As soon as the trigger is pulled and there’s light, that shade turns darker and protects the eyes. With that, the helmet can easily be kept on at all times without running the risk of damaging their eyes.”

One of the most common mistakes welders make while they work at such a rapid pace is welding while sweating.

“It’s very important for the person welding to remain dry,” Kolasa says. “If you’re out there in the sun, sweating and getting wet, that’s where we see people getting hurt. You can start welding on something and be perfectly dry and safe, but when you start sweating on your gloves and things like that, then the body starts to become conductive and you can get shocked.”