OBJECTIVE: AM24.02 Identify, cut, drill, bend, shape, file, and grind cold metals.

Identifying Metals  Ferrous contain iron– must be painted  Nonferrous has no iron  Metals Color Weight Texture Use Shape Spark test

Identifying Metals  Spark Test Cast iron- red lines High carbon steel- yellow lines/star bursts Wrought iron- straw colored lines w/o bursts Galvanized steel should not be cut or welded

Drilling  Center punch  Drill- use oil  Use round file to smooth hole

OBJECTIVE: AM25.01 Examine oxy-fuel procedures.

Oxy-Fuel Procedures  Used to cut through metal, heat for bending, or for welding  Fuels include propane, propylene, or acetylene  Acetylene is most often used  Oxygen enhances the flame-will not burn

Oxy-Fuel  Use soapy water to check for leaks in hoses  Acetylene pressure should be less than 15psi  Open the acetylene valve ¼ to ½ turn  Only use spark lighter

Types of Flames  When first lit, you have a carbonizing flame  Oxygen is adding to make a neutral flame  Extra oxygen makes an oxidizing flame for special applications where extra heat is needed

Arc Welding  AC- inexpensive welder used most of the time  DC- generator operated, used where power is not available  Some welders are both AC and DC

Welding  TIG- Tungsten Inert Gas  Good for welding stainless steel & aluminum  Gas supply is helium & argon

MIG Welding  Metallic Inert Gas  Wire feed welder  Can be used as automatic welder

Welding Equipment  Helmet  leather gloves  leather aprons  leather welding jacket  leather boots

Welding Equipment  Chipping hammer  Clamps  Vise grip clamps

Electrodes  Rods covered in flux  Have a classification system Example: E6011

Electrodes  6011 is good for all purpose work  6013 is also good but only has medium penetration

Welding Procedures  Metal should be cleaned before welding  ¼” or thicker metal should be beveled & place 1/16 to 1/8” apart

Setting the Amperage  Amperage too low causes a narrow, high bead with poor penetration.  Amperage too high caused a flat bead with excessive spatter.  Correct amperage helps make a uniform bead with bead width and penetration depth equal to each other.

Welding in the flat position  When the electrode sticks, wiggle it back and forth  Tapping or scratching methods can be used to strike an arc  Arc length should be the same as the diameter of electrode.