Tools & Equipment
Hand tools, power tools, brakes, slip rolls, shears, notchers, crimping tools, and rotary machines for sheet metal work.
- Identify the correct aviation snip color for different cutting directions
- Describe the purpose and operation of a slip roll machine
- Explain the function of a squaring shear for straight cuts
- Identify the purpose of crimping, hand grooving, and rotary machines
- Describe the proper cutting technique for aviation snips
Lección 1
Hand Tools & Aviation Snips
Aviation Snips
Aviation snips (compound-action tin snips) are the most frequently used hand cutting tool in sheet metal work. They are color-coded by cutting direction:
The exam specifically tests this: yellow aviation snips cut straight and wide right curves. Red snips cut left curves, and green snips cut right curves. The color coding follows a standard used by all manufacturers.
Proper Cutting Technique
The proper cutting technique for aviation snips is to:
- Open the snips fully for each cut stroke
- Keep the waste piece curling away from the cutting line
- Never close the blades completely at the tip - this causes burrs
- Support the workpiece to prevent distortion
- Cut with the lower blade following the layout line
Snip Selection
When cutting a circle from a sheet, use green (right) snips cutting clockwise or red (left) snips cutting counterclockwise. The waste piece always curls away from the cut.
Hand Groover
The purpose of a hand groover is to close and flatten grooved seams in sheet metal ductwork. The hand groover has a groove matching the seam profile and is struck with a mallet along the seam length to lock the joint tight.
Yellow aviation snips cut straight and wide right curves. Red cuts left, green cuts right. Always keep the waste piece curling away from the cutting line and never fully close the blades at the tip.