Welding, Brazing, and Soldering

Overview

Anyone who plans to use advanced procedures such as welding, soldering, laser cutting, or CNC machining must first complete the proper training. This training should be scheduled with the shop staff and is generally reserved for the principles of the project teams (Mini Baja, Rocket, Steel Bridge, and Robot Team).

Welding, Brazing, and Soldering Safety Rules

1. Always wear personal protection equipment appropriate to the task. This includes safety glasses, the proper gloves, a welding jacket, and the proper face mask.
2. Before performing any welding operation you MUST alert a shop technician.
3. Never weld alone. Someone should be present to assist in the event of an emergency.
4. CAUTION: Welding arcs should NEVER be observed with the naked eye – they have the potential to blind you.
5. All hot items will be left in the welding area and marked appropriately. Handle all hot pieces with extreme care.
6. Dangerous voltages are present with all welding operations. Inspect cables before any welding.
7. There are always fire hazards with any welding operations. Have a fire extinguisher at hand.
8. Always vent fumes from welding, brazing, soldering, and cutting operations.
9. Material should be cleaned to prevent fire and fume hazards. No painted materials should ever be welded.
10. Remove all flammables from surrounding area. Rags, paper and wood should never be kept on the welding table.
11. Anytime welding is performed off the welding table, special care must be taken to keep anyone from seeing the arc or touching the hot piece.
12. Wear only clothes of natural fibers (such as cotton, wool, or leather).
    
     

 

Welding, Brazing, and Soldering Methods and Materials:

• Brazing and silver soldering: Uses an oxy/acetylene torch and a project dependent filler material. Used to attach dissimilar metals, steel, stainless steel, copper, and brass.
• Soldering uses a torch or electric soldering iron with soft lead based filler material.  Best used on small delicate parts and circuit boards.
• Torch Welding: Uses gas torch as heat source with steel filler rod.  Used for mild steel.
• Shielded Metal Arc Welding (SMAW): Commonly called stick welding.  Uses power supply and fluxed rod as filler and electrode.  Used for welding mild steel, stainless steel, and cast iron. Very portable and easy to setup. Generally used on job sites.
• Gas Metal Arc Welding (GMAW) - MIG (Metal Inert Gas): Uses power supply with electrode that is both heat source and filler metal.  Requires the use of a wire feeder to feed the filler metal through the gun for welding.  Uses gas as shielding to prevent oxidation in weld, generally carbon dioxide and argon mixture.  Used primarily for production welding and sheet metal work.  Easily automated through the use of robotic welding arms.  Generally used for mild steels, but can be used for welding stainless.  Is possible to weld aluminum by using a spool gun or push-pull gun.
• Gas Tungsten Arc Welding (GTAW) – TIG (Tungsten Inert Gas): Uses power supply and tungsten electrode as heat source.  Filler metal is dependent on materials being welded.  Uses inert gas (argon, helium, or mixture) as shielding to prevent oxidation in weld.  Primary method for welding aluminum, stainless steel, and other exotic materials.  Requires the cleanest material preparation before welding, but also yields the cleanest and most aesthetically pleasing welds.

Setup – clamping, square edges, tack welding, and material preparation