BodyShop Business
  Repair
How Are Your Shop's Welds?
6/2/2014

After a destructive weld test, a proper weld will have torn metal out of the base material, not at the weld.
When I sat down to write this article, I tried to think of a clever opening paragraph. When I couldn’t come up with anything, I wasn’t too upset because I realized being clever wasn’t important – but doing quality welds is. Asking “How are your shop’s welds?” is a serious question with serious ramifications. It’s also a controversial subject.

Some may be offended, others may be mortified. Still others may learn. The questions are familiar. For technicians, they are: How good are your welds? How do you know? For managers, the questions are: Do you know if a weld is good or not? How do you know?

Wow and Not-So-Wow
Before I go any further, let me preface this article by saying that as I travel this country and see many types of shops from all different areas, I’m tickled at how much pride many technicians take in their work. The quality in this industry keeps amazing me. In the last year, I’ve been seriously wowed on my trips. But I’ve also seen shops that didn’t wow me.

I started asking all the shops, “What makes you run?” The “wow” shops all had the same answer: investing in employees. Not just training, but including them on shop issues. Creating a team, not just employees. Helping them see the big issues and understand why things need to be done. Accountability was a common word used. The “not-so-wow” shops had excuse after excuse, blaming someone else. Accountability struck a chord in my head.

Types
One of the most common and important procedures the collision industry does is weld. We do various types of welds, including Gas Metal Arc Welding (GMAW) in the form of Metal Active Gas Welding (MAG) with 75 percent argon/25 percent CO2 (or a similar combination) and Metal Inert Gas (MIG) with 100 percent argon. This includes aluminum and silicon bronze welding. Many shops have also invested in a Squeeze Type Resistance Spot Welder (STRSW). No matter what type of welding or machine you have in your shop, the question to all technicians and managers is: How good are your welds? When was the last time you checked?

The I-CAR welding test (WCS03) showed me some interesting things, including that many technicians are great welders. It also showed that many technicians don’t know how to set up a welder. Do yours? Do you?

Ask most technicians who took the I-CAR WCS03 test and they’ll tell you they learned a lot about welds and machines. Most comment that the test improved their welding and understanding of the importance each weld has to a vehicle structure. Training for many like myself was a long time ago, so many basics have been forgotten. I don’t know of any profession where, after a long time, a refresher course isn’t needed.

Good vs. Bad
What makes a good weld? Without getting too technical, it takes:
  1. A person to weld. (This includes the ability to see where they’re welding).
  2. A welder that is correct and set correctly for the material to weld.
  3. Training of the operator to use the welder.
If any of these three categories aren’t working correctly, a bad weld will be made or won’t be depending on how you look at it. So let’s break some basics down.

Technicians
  1. Do they have the correct safety equipment? Protective clothing? Respirators? Do they use them?
  2. Vision. Do they wear glasses? If a technician needs to put on glasses to read instructions or car labels, glasses or cheaters might need to be one of their required tools. You need to see the weld to make a quality weld.
  3. A welding visor seems to be an option for many technicians. “Look away” welders are abundant in our industry. If you hear or see a welder, check to see if they’re wearing a visor. There seem to be a lot of hand shielders, too, or people who can see the weld just by holding up their hands in front of the arc. However, this will burn out your eyes quickly.
  4. Respirator. Welding galvanized steels and other metals may produce fumes that contain heavy metals, which can lead to serious health issues. Many shops I see forgo the respirators and instead have fans blowing on technicians. The problem with this is that the shielding gas you need to make a quality weld also gets blown away.
Moving a piece of the test weld back and forth using a duck bill vise grip until it breaks can show you if your weld is sound.
Moving a piece of the test weld back and forth using a duck bill vise grip until it breaks can show you if your weld is sound.
Welders

  1. Proper power supply. Do you have extension cords attached? Are you supposed to? Does your shop have enough power at that outlet? If four other people are operating equipment on that same circuit, who might not be getting correct power?
  2. Properly maintained machine. Are the tips correct and not damaged? Is the nozzle in good shape and correct for the application? Are the rollers for the wire clean and correct? Improperly maintained machines are a big reason for failed welds and technicians struggling to weld. This has a huge impact on production.
  3. Proper wire. Is the tensile strength correct and/or the alloy for application according to the vehicle manufacturer? Is the liner clean? Is the helix correct? Is the wire diameter correct?
  4. Settings. Are the settings for the material correct? Check inside the wire panel for directions on this.
  5. Gas and gas settings. What type of gas? Are you supposed to be MIG or MAG welding? What PSI should the gas be?

Training
  1. Does the technician know how to set up the machine? This sounds like a “duh” statement, but you would be surprised at how many don’t know how to do this. They just keep making adjustments until it sounds good.
  2. Do they understand the parameters of the adjustments? Just because it sounds good doesn’t mean they’re making good welds.
  3. Do they know how to prep metal for welding? Do they understand thickness of material? Corrosion protection? Contamination?
  4. What type of weld do they need to make? Continuous plug stitch or skip?
  5. Depending on the type of welding required for specific metals (wire or weld), do they use the push or pull technique?
  6. Do they have or use a shunt during STRSW or spot welding?
  7. Do they know when MIG brazing is required?


I could ask many more questions in each category, but I think you get the idea. If you’re a shop owner or manager and your answer to these questions is yes for every technician who welds in your shop, awesome! Now, just one last item needs to be done: show me. I don’t want to see how pretty the weld is; I want to see how strong it is. A big wake-up call is a video in the new I-CAR course (FFR01) that shows a weld being done on a frame. One welder was properly powered, and one wasn’t. The welder that was set correctly and had the proper amperage to weld the frame did great. The welder that was underpowered made a good-looking weld, but the weld failed miserably. The lesson here is that looks can be deceiving.

Test Welds
Because looks can be deceiving, I’m a big fan of test welds prior to welding on a vehicle. A test weld is the exact weld being made on the same thickness and position of material, preferably damaged metal from the vehicle that’s going to be discarded. Following the test weld, a destructive test done in a vise will properly indicate if you’re set to weld the vehicle.

Another reason to do a test weld is that many welders don’t make a good quality weld cold. Electronics, moving parts, triggers and relays need to warm up for the best results. If there’s a problem with the machine, welding on the vehicle being repaired is not the place to find out.

Too many times, technicians get out the welder and set up and start welding on a vehicle. The person who used the welder before could have made the settings way off, or the tip could be garbage. It may take a weld or two or four or five to figure it out. The point is, how many practice welds does a vehicle manufacturer allow to be done on a vehicle? How many of these practice welds could fail? How many could cause corrosion? How bad could this get? How quickly can a shop’s reputation be destroyed by one technician in a shop? This is why we ask for test welds. And by asking for test welds, all technicians welding in the shop – not just one technician or a role rep – know what’s expected. Back to accountability. Remember, it isn’t just your reputation on the line. Your customers are betting their lives on these welds.

Eliminating the Bad

A test weld gives you the benefit of knowing that all your technicians know what they are and what they need to do. The test weld gets the bad out of the system. Many first welds or cold welds fail destructive testing. Why would any shop or technician want this weld anywhere on a vehicle? The test weld gives you, as a manager and owner, the confidence that your technicians know how to test and judge their own work, too. The little bit of time preparing and testing can help you avoid or reduce many comebacks for quality control or, in worst case scenarios, issues in a crash. This will also show that the shop followed the repair procedures required by vehicle manufacturers. During re-inspections, many times it’s the welds that cost a shop.

When a weld is made, follow all dressing and corrosion protection procedures to maintain its longevity. You can be an awesome welder but blow it all out the door by not following corrosion control procedures.

Maintenance is a major problem for any welding machine. A shop can spend a serious amount of money for the best welder out there, but if it’s not maintained, it becomes a drain on time and resources. Keep a regimen for all to maintain and clean your machines. Simply put, maintain what makes you money!

Don’t Assume
We’ve all heard the parable about assuming anything. We assume all techs know how to weld. We also assume that they know how to weld correctly, and that management knows the difference between a good weld and a weld that does not pass the test. Do you?


Mitch Becker is a technical instructor for ABRA Auto Body & Glass. Contact him at (763) 585-6411 or
[email protected].

 



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