Having the appropriate welder in your farm shop is crucial for saving time and money on repairs and fabrication. MIG welders have gained popularity on farms, but stick and TIG welders also have their uses. This article focuses on MIG welding and provides general techniques and safety precautions. For tips on other types of welding, visit Agriculture.com/welding.

Unlock the Potential of Welding in Your Farm Shop

MIG Welding

MIG (metal inert gas) welding, also known as FCAW (flux-cored arc welding), is a popular choice for many farmers due to its ability to create clean welds on various materials. It offers a reliable and efficient way to join metal parts. 1: The No. 1 failure of a MIG weld is porosity, often caused by welding dirty, oily, or painted surfaces. Contaminants get trapped in the weld, resulting in holes. Other factors like inadequate shielding gas coverage or improper wire stickout can also lead to this issue. Farmers often fail to properly prepare the metal before welding, which includes removing paint, rust, dirt, and cracks. Hydrogen, the worst weld-destroying impurity, is everywhere and careful cleaning is essential to mitigate its presence. 2: A welding arc requires a smooth flow of electricity through a circuit. The ground should be placed near the arc to ensure a good connection. Copper ground clamps with strong springs are the best. If you hear popping or crackling sounds when welding, it may be due to a poor ground clamp. Firmly attaching the clamp to bare metal close to the arc helps improve welder performance.

MIG Gas Selection Tips

For MIG welding, 100% carbon dioxide (CO2) is an economic and efficient choice. However, for thin metal, it may be too hot. A mixture of 75% argon and 25% CO2 is suggested. Other shielding gas mixtures are also available for specific uses. 1: Use 75% argon and 25% CO2 for nice-looking welds and high amperage welding. 85% argon and 15% CO2 is suitable for welding heavier-plate steel or metal with mill scale or rust. 90% argon and 10% CO2 is ideal for spray transfer welding and heavy/thick metal sections. 100% argon or an argon/helium mixture is used for welding aluminum, and 98% argon and 2% CO2 for stainless steel. For most farm shop needs, having CO2 and an argon-CO2 mixture on hand is sufficient. 2: Choosing the right gas mixture depends on the specific welding task and the type of metal being welded. Each gas combination has its advantages and considerations, and farmers need to select the appropriate one based on their needs.

MIG Wire Selection Tips

Although the common wire diameters are.035 and.045 inch, a smaller-diameter wire like.025 inch can be beneficial for certain materials. 1: When welding material 3⁄16 inch or less, a.025-inch wire diameter can produce more stable welds at a lower current, reducing the risk of burning through. However, on thicker materials (3⁄16 inch or thicker), using a.025-inch wire may cause lack of fusion. Farmers need to be careful when choosing the wire diameter based on the thickness of the material. 2: Safety is of utmost importance when selecting MIG wire. Using the correct wire size and ensuring proper equipment compatibility helps ensure a successful weld. Regularly cleaning and maintaining the gun liner, drive rolls, and contact tips also contributes to better welding performance.

Aluminum Welding Tips

More agricultural equipment is incorporating aluminum, requiring the ability to make repairs. Any wire welder can handle aluminum with the right techniques. 1: When welding aluminum, use U-groove drive rolls that support the wire without crushing it and keep the drive-roll adjustment on the loose side. Replace the cable lining with a Teflon, nylon, or similar liner product. Only use argon or argon-helium gas. Select an aluminum filler wire with a diameter of 3/64 inch or 1/16 inch for easier feeding. Employ a contact tip approximately.0015 inch larger than the wire diameter. Remove grease, oil, manure, and dirt using an organic solvent. Brush the repair with a new stainless-steel wire brush to remove the oxidized aluminum. 2: Preheat the repair to no higher than 230°F to minimize cracking and place tack welds at the beginning and end to aid in preheating and prevent distortion. Use a short gun and a straight cable. If doing a lot of aluminum welding, consider a spool gun. Push into the weld to reduce contamination and improve shield gas coverage. Weld hot and fast using higher amperage and voltage settings and faster weld-travel speeds to prevent burn-through. Fill the weld crater at the end to prevent cracking. If not welding immediately after cleaning, cover the joint with brown kraft paper.

Safety Precautions

A good auto-darkening helmet is essential for a good weld. It allows you to see where the wire is pointing before welding. Leather footwear and flame-resistant clothing without cuffs or open collars are recommended to prevent burns. 1: If using an extension cord, use the shortest length and biggest diameter possible. Ensure the welding equipment is on a flat surface away from flammable materials. Avoid working in damp or wet conditions and keep the work area clean. Never pick up hot metal with your hands; use pliers instead. 2: Good ventilation is crucial to protect from fumes, dust, and particles during welding. A fan can help pull fumes away from the breathing area. By following these safety precautions, farmers can ensure a safe and successful welding experience.Many farmers rely on MIG welding to keep their equipment running smoothly. With the right techniques and safety measures, they can achieve excellent welds and save time and money.