Welding is just as important to any good race program as driving or turning wrenches. It doesn't matter what class you race, all cars require fabrication and the occasional repair. And if your welding isn't up to par, you'd better believe it's going to show up in your results on the racetrack.

The good news is, welding isn't voodoo or an art that requires a lifetime of practice to master. Modern welding methods (either MIG or TIG) are simply an electro-mechanical process that just about anybody can do with the right knowledge. Of course, in order to go from "good" to "great" as a welder, it requires a bit more than a basic level of knowledge. For that we went to Miller Electric's Andy Weyenberg. Weyenberg handles all of Miller's racing applications and is even a stock car racer himself. So he spends his days helping racers-which includes everyone from the NASCAR Sprint Cup teams down to the hobby-level racers-weld a little better so they can go a little faster and be a little safer. We asked him to provide us with some of his best tips when it comes to welding, and here's what he said:

1. Pick The Right Tools "Pick the machine size for the work you do most. Welders have an amperage rating that determines the material thickness you can weld. If you only need to weld aluminum twice a year, you may want to job that out and just purchase a machine that does steel."

2. Consumable Matching "If you are running 0.030 wire in your MIG welder, make sure the liner, drive rolls, and contact tips match. Any mismatch will cause feeding and weld consistency problems."

3. Right Wire "Pick the right wire size for the job. Don't use 0.035 wire to weld 22-gauge steel. As a rule of thumb, the wire shouldn't be bigger than the thickness of the material you're welding. If it is, you'll spend most of your time blowing holes in the base metal instead of melting the weld wire."

4. Stay Grounded "You should frequently check the condition and connection of the ground cable. Loose or bad connections, as well as cables in poor condition, will cause excess heat. That heat is a loss of welding current you should be using at the arc. You can't jump-start a car with a lamp cord, so don't weld with one, either. A welder needs heavy cables in good condition to weld effectively."

5. A Tip For Your Tips "Don't be afraid to change your contact tips. They are not made of gold and they do wear out. Also keep them tight and check them often. They do loosen up from heating when you are welding then cooling back off again."

6. You Can't Weld What You Can't See "Get a good welding helmet with a nice view area and keep the lens clean. You can't weld what you can't see. The electronic auto-darkening helmets are nice. You can adjust shading to your preference, and they allow you to see where you're starting to weld before it turns dark."

7. Material Prep "Paint, rust, and mill scale are your enemies. Clean the joint area before welding with a grinder or a sander. You can also use a wire brush or other metal cleaner."

8. Keep Your Joints Tight "Joint fit up is critical. Keep the joint tight. Good weld joints are usually seams, not holes and gaps."

9. Be Tacky "Tack joints on alternate sides to reduce pulling. Tack tubes the same way and weld in sections, keeping the gun angles the same if possible. Very few people can weld nonstop around a tube and keep the gun at the proper angle consistently all the way around. Changing your gun angle from a push to a pull, or pull to push, will change the penetration of the weld and the joint appearance."

10. Heat Sinks Help Warpage "When welding thin material, you may want to place a thicker piece of copper or aluminum behind the weld area to help "sink" the heat away to prevent warpage. This also helps prevent burn-through."

11. Got Gas? "For MIG welding on steel, a 75/25 Argon/CO2 mixture will give great results. Straight CO2 can also be used to get more penetration, but this gas will also produce more spatter. Typical flow rates are 25-30 CFH. If you have your flow too high, it will cause turbulence and contamination. But if the flow is too low, it will not give enough shielding of the weld area and also produce porosity of the weld bead. For all TIG processes and whenever you're using a MIG with aluminum, 100 percent Argon gas is used. Flow rate depends on cup size, with most flow rates being around 12-20."

12. Get A Grip "Clamps, vise grips, and magnetic squares are your friends."

13. Never Forget: Wood Burns "If you're welding on a table, get one with a thick metal top. A top with a 1/4-inch steel plate or thicker will not warp while you're welding on it. Do not place a metal plate on top of a wooden table and think you can safely weld on it. It will still burn the wood. I know it sounds stupid, but people still do it."

14. Grinding Tungsten "When TIG welding steel, grind your tungsten tip to a point using a fine grit grinding wheel dedicated only to tungsten. Grinding anything else on that wheel can cause the tungsten to become contaminated, and that will affect the quality and strength of your weld."

15.Know Your Elements "TIG tungsten types are as follows: 2 percent Thoriated (red band) for steels and Pure (green band) for aluminum. This is true unless you have an Inverter type TIG machine. Most Inverter type TIG units can run on sharpened 2 percent Thoriated or Ceriated (orange band) for EVERYTHING. NO GREEN Tungsten."

16. To Push Or Pull? "When MIG welding, it doesn't really matter if you use the gun in a pushing angle (pointed toward the leading edge of the puddle) or a pulling angle (pointed away from the leading edge of the puddle), just stay consistent while welding. Changing from a push to a pull during a weld will affect weld penetration and appearance. This is because it normally takes a slight change in wire speed when changing from pushing the gun to pulling it. Also, the angle of the gun determines if the weld wire is hitting the colder edge of the puddle (as in a push angle) or pointing to the hotter part of the puddle (pulling).

"The pull gives you deeper penetration, so if you're welding thinner material use the push method to prevent burn-through. With TIG welding there is no exception. Always push the torch at a 10-15-degree angle if possible. Never pull the TIG torch. This ensures you have proper gas coverage and cleaning of the weld zone. If you pull the torch, it causes the weld bead to appear black and contaminated."

17. Through Thick And Thin "When welding two materials of different thicknesses, concentrate or point the gun more at the thicker material and roll the bead to the thinner material. This will help you achieve adequate penetration on both the thick and thin piece without blowing through the thinner piece of material."

18. Find Your Comfort Zone "When preparing to weld, especially in TIG, get comfortable. Prop yourself up so you are not suspending the gun or torch in mid air. Put something under your hand to get situated for proper weld angles. In MIG, use both hands to grasp the gun. This helps stabilize the gun and reduces the chance of jerky movements ruining the quality of your weld. Do a dry run with the gun or torch to get positioned properly for the joint you're attempting to weld."

19. Find Good Resources "Don't be afraid to take a night course at your local tech school. They are good resources for the particular weld process you're trying to learn. They also cover some basic metallurgy for matching filler metal and base metals. Your local welding distributor can also help you with filler metal selections."

20. Finally, Safety First "As always, safety first. Welding sleeves and gloves will keep you from burning your skin. The rays from a welding arc will burn you faster than sitting on the beach. Plus, I'm sure your wife won't appreciate the stink of burned skin when you roll into bed after a night of welding on your racecar. Welding helmets are a must, at least to protect your eyes. Anyone with a bad case of welder flash can tell you they would rather take a mixture of salt and acid in the eyes. A welder's cap or beanie is nice, too. Some of the better ones cover your ears. You haven't lived until you're welding under your rig and a hot molten weld spark rolls down your ear and parks itself next to your brain and sizzles for a while.

"Finally, keep flammable material away from weld sparks. This is another common-sense thing that too often gets overlooked. I am guilty of this one. The most common fire hazard is grease- or oil-soaked rags lying around your work area."

Well, there you have it: 20 Tips to Welding Bliss. Now you can get to work on that racecar.

SOURCE
Miller Electric
8-004-AMI-LLER
www.millerwelds.com
  • «
  • |
  • 1
  • |
  • 2
  • |
  • View Full Article