Cutting is where most metal projects begin: reducing stock to size before forming and joining. This overview covers the main cutting process families used in small shops — sawing, shearing, abrasive cutting, and thermal cutting — in general terms, along with conservative safety reminders.
Sawing
Sawing uses a toothed blade to cut through metal. It is versatile and can produce straight or curved cuts.
- Process Variety: Hacksaws, band saws, and circular saws are common in small shops.
- Material Suitability: Sawing suits a wide range of metals, from soft aluminum to many steels.
Shearing
Shearing cuts sheet metal with two blades that pass each other, like heavy-duty scissors.
- Process Features: Fast and clean for straight cuts in sheet material.
- Material Suitability: Best for thin to medium-thickness sheet metal.
Abrasive Cutting
Abrasive cutting uses a rotating abrasive wheel to grind through material.
- Process Variety: Includes cut-off wheels and abrasive chop saws.
- Material Suitability: Effective across many materials, including steel and stainless steel.
Thermal Cutting
Thermal cutting uses heat to cut metal. Two common methods are plasma cutting and oxy-fuel cutting.
- Plasma Cutting: Uses an electric arc and a high-temperature gas stream to cut electrically conductive metals.
- Oxy-Fuel Cutting: Uses a flame combining oxygen and fuel gas to cut steel by oxidation.
- Both methods produce heat, sparks, and fumes and require hot work precautions.
Choosing a Process
The choice of cutting process depends mainly on the material and the job:
- Material Thickness: Thin sheet is often sheared or sawn; thicker sections may suit thermal cutting.
- Precision Needs: Finer work may favor sawing or abrasive cutting.
- Shop Conditions: Thermal cutting demands ventilation and fire precautions that mechanical cutting does not.
Blade and Consumable Care
Cutting tools work best when maintained:
- Inspect Regularly: Check blades and wheels for wear, cracks, and damage before use.
- Store Dry: Keep blades and consumables clean and dry to prevent rust and damage.
- Replace Promptly: Worn consumables cut poorly and work the machine harder.
Safety Reminders
- Machine Guards: Keep all guards in place and functional.
- Eye Protection: Wear eye protection whenever cutting equipment runs.
- Hot Work Precautions: Thermal cutting creates sparks and heat; clear the area, keep a suitable extinguisher nearby, and stay with the work until it cools.
- Ventilation: Remove dust and fumes with adequate airflow.
These reminders are general. Always follow equipment manuals, applicable codes and standards, and professional guidance for every cutting process you use.