How to Weld with a Welding Machine?
Arc welding is a method of joining two or more materials with electrically generated heat. Stick welding is one of the most common and versatile forms of welding, and is a relatively easy way to add professionalism and durability to your DIY projects.
1. Gather your materials. You should have a welding machine, electrode holder with lead, ground clamp with lead, electrodes, and metal to be welded. You will also need a chipping hammer to get rid of the slag and a wire brush to clean the welds.
2. Put on your safety gear. This includes a welding helmet, welding jacket or cotton sweatshirt, pants without cuffs, work boots, gloves, and safety glasses.
3. Prepare the area to be welded in. Remove all flammable material and find a good surface to weld on. Although you can put the ground connection right on the piece you are welding, most shops have a large metal workbench that the ground is hooked up to.
4. Set up the machine. Most welding machines are fairly straight forward. You should most likely be using an amperage of around 90-120 amps, although this should be adjusted for metal thickness and electrode diameter.
5. Use the correct electrode. DCEP (direct current electrode positive) sets the arc to go from the metal to the electrode, heating the metal more. DCEN has the reverse effect. For stick welding, DCEP will give your weld more penetration. You should select the electrode appropriate for AC or DC welding, depending on your machine. Make sure the electrodes are dry.
6. Clean the metal before welding. This can be done by brushing the surface to be welded with a wire brush or a grinder. Remove as much rust or paint from the metal as possible.
7. Set the joint. Use clamps and vises to ensure that the joint you are welding is precisely and firmly held together.
8. Strike a welding arc. This is accomplished by tapping the metal and quickly pulling up or striking it like a match. You are completing the circuit and pulling away, which causes the electricity to jump from the electrode to the metal.
9. Build up a weld pool. When a stable arc can be maintained, ignore the end of the electrode and instead watch the pool of molten metal. To create a good pool, you should stay where you started for seconds before moving.
10. Start moving the weld pool across the metal. Keep the electrode at an angle a few degrees shy of 90°. Don't travel too fast. As a general guide, you may want to use an inch of electrode for each inch of weld. When moving the weld pool, you can go in a straight line or move around in small circles.
11. Finish the weld. Pull the electrode back from the metal and allow it a few seconds to cool. The metal will still be very hot at this point, but it should no longer be red hot.
12. Clean the slag. Slag is a residue left from the welding process. During the weld, the slag protects the hot metal from contaminants. The slag covering does not cool at the same rate as the weld bead, which can cause the slag to pop off the weld. Use the chipping hammer to break the slag off the weld.
13. Examine the weld. A welder's first welds are often poor and do not take stress well. But you can make another pass to fix any gaps or incomplete welds.
14. Allow the metal to cool. Cooling in water will make the weld brittle, so allow any structural welds to cool by air instead.