Ok so you've got your MIG welder and you can finally make two pieces of metal stick together, but now you want to learn how to make those welds look nice AND be strong. In this quick 10 step guide we will give you the tips to make your welds look great, and be as strong as possible.
1. Cleanliness is King- We understand that there are times you can't always get a work area surgically clean when MIG welding, but you should take every step possible to do so if you want a clean, strong weld. The work area should be free of ALL rust, grease, and coatings. We have found that using a wire wheel on an Electric Angle Grinder makes quick work of rust, undercoating, and other coatings. Be sure to prep the work area before and after welding with Eastwood After Weld. You will amazed at how much better your weld puddle will form and look when performed on a clean surface.
2. Check your Gas- In order to make a clean weld, your weld puddle needs to be purified while it is being formed. This is where shielding gas comes into play. It is one of the other essential keys to making a clean weld. Make sure you have an adequate amount of gas coming out of the nozzle when welding, the amount needed can vary on the conditions where you are welding (try to be out of any direct moving air like fans, wind, etc), and the surfaces you are welding on. MIG welding can be done with machines that only use Flux Core MIG wire, but we suggest choosing a MIG Welder that is versatile enough to use gas as well. Welding with a shielding gas is the best way to make the cleanest weld with little to no clean up.
3. Sounds like Bacon- You want to set up your machine correctly before welding anything. If you aren't sure of the correct setting for the job, we suggest getting some metal that is the same gauge, and taking the extra time to set up your machine properly. The key to quickly dialing in your machine is listening to the sound of the arc when welding. You ideally want the arc to sound like "sizzling bacon", not too much popping or spitting, just a nice even sizzle/crackle sound. The next is to make sure the bead is nice and flat. A common error with beginners is that the bead is sitting very "proud" and piling up on top of the metal. In those cases you often times need to either turn the wire speed down, or the heat (voltage) up. Once you learn to listen to your welder and how the arc sounds, and how the bead "should look", your welds will instantly improve.
4.Proper Joint Construction- Another mistake when a beginner is welding up a joint, is that they leave too large or uneven of a gap in between the two panels they are joining. On some joints you may want a very small gap, but most there will be next to no gap between the panels when welding. Too large of a gap, and you will have difficulty with the bead burning the edges of the two panels away and opening the gap up even more. Again, taking the time to put together an even, tight gapped joint will make the final appearance and strength of the job much better. Our favorites for proper joint prep is our Intergrip Panel Clamps, Clecos Panel Holding System, and our Welding Clamp Plier Set, they really make the job much easier!
5. Check your Ground- Found your welder is welding poorly or inconsistently, even after testing your settings on some scrap metal? A good chance is that you have a poor ground. Not only do you want to have as clean of a work area as possible, but you need a clean surface to ground the machine through. A little tip if you don't have a good spot to clamp to, is to tack weld a bolt or a stud to the work area to get a good continuous ground. Try it, it really is handy!
6. Auto-Dimming Helmet; it's not just for NASA!- The age old tradition was to use a static darkness welding helmet when welding. These work "ok" if you are in a very well light area, or if you are good at flipping your helmet down and striking an arc all in one quick motion, but with the advancements in modern day welding accessories, it isn't necessary anymore. Now you can find affordable, quality Auto Dim Welding Helmets pretty easily. Being comfortable when welding helps you make quality welds, and allows you to properly see your work area before, during, and after you weld.
7. Stickout makes a difference- When setting up your machine, you need to make sure that you have the contact tip sticking out the correct amount for the type of welding you are doing. The general rule of thumb is that you want your welding tip to have less than 1/2" of stick out. If you are welding on thinner sheet metal like body panels, you can get away with a little more, but you need to stick in that range for most applications. Always check your stick out each time before welding.
8. The Angle matters- The angle of the tip when welding can also be just as important when running a bead. Ideally you should be straight on when doing quick spot or plug welds, while keeping approximately a 10 degree angle when welding with the pushing or pulling method is satisfactory.
9. Choose the correct wire size- In this case "bigger is better" is not always true. It all depends on the type of welding you are doing, and the surface you are welding on. If you are mostly working with thin metal like body panels of a car, you'd want to stick with .023 solid core wire. This will allow you to keep the temps down versus using a much thicker wire. And if you didn't know, too much heat equals metal warpage, which is BAD in the autobody world. Keep in mind though, if you are doing suspension or chassis work where the metal is substantially thicker, you'd want to upgrade to .30 or .35 solid core wire. This will require 110V machines (like our MIG 135) to run at the higher end of their voltage spectrum.
10. Be Safe- There are a lot of hazards when welding, a lot of them are quite obvious, while others can easily be overlooked. Make sure to wear the proper attire when welding. This means closed toe shoes (preferably leather work boots), long pants, Leather Welding Gloves, and a Welding Jacket. Dressing properly can save you from being severely burnt from the intense light and heat produced when welding. Also keep in mind that you need to keep your work area safe, which means covering or removing all flammable objects from your work area, as well as allowing for proper ventilation from any fumes that could be produced when welding.