What tool should I use to cut metal? The right tool depends on the type of metal, its thickness, the shape you need to cut, and how fast you need to work. For thin metal sheets, simple shears work well. For thicker metal or pipes, power tools like saws or grinders are often needed. Choosing the correct equipment makes the job safe and easy.
Choosing the Right Tool for Metal Cutting
Cutting metal is a common task in workshops, construction sites, and even around the home. Metal cutting tools come in many forms. Some are manual, requiring muscle power. Others use electricity or compressed air to move very fast. Knowing your project needs helps pick the best tools for cutting metal. We will look at the main types available.
Factors Guiding Tool Selection
Before picking up any tool, think about these points. They change what tool will work best for you.
- Metal Type: Is it soft aluminum, tough steel, or thick stainless steel? Different metals need different cutting forces.
- Metal Thickness: Thin sheet metal is easy to cut. Thick bars or pipes need much stronger tools.
- Cut Type: Do you need a straight line, a curved shape, or a precise hole?
- Speed and Volume: Are you making one small cut or many large cuts? Speed matters for big jobs.
- Portability: Do you need a tool you can easily carry to the work site?
Manual vs. Power Tools
This is the first big choice. Manual tools are quiet and need no electricity. Power tools cut much faster and handle thicker stock.
| Tool Type | Pros | Cons | Best Use Case |
|---|---|---|---|
| Manual | Cheap, quiet, portable, good control | Slow, tiring, limited thickness | Small jobs, thin metal, no power access |
| Power | Fast, handles thick metal, less effort | Loud, needs power source, more costly | Production work, thick material, speed needed |
Simple Handheld Metal Cutters
For light work, handheld metal cutters are excellent choices. They offer good control over the cut.
Tin Snips and Aviation Snips
These look like heavy-duty scissors. They are ideal for thin sheet metal, like ductwork or flashing.
- Tin Snips: Best for straight cuts on very thin metal. They use leverage to shear the material.
- Aviation Snips: These are stronger. They come in three types: straight cut, left cut (for curves to the left), and right cut (for curves to the right). They can cut thinner gauge metal much better than regular snips.
Bolt Cutters and Cable Cutters
These are heavy-duty shears for cutting sheet metal components, though mainly used for rods or chains.
- Bolt Cutters: They use long handles and powerful jaws. They are designed to snap through bolts, chains, and metal rods quickly. They are not good for flat sheets.
- Cable Cutters: These specialized cutters use a powerful shearing action to cleanly slice through thick electrical cables without crushing the inner wires too much.
The Hacksaw for Metal
The hacksaw for metal is a classic, budget-friendly tool. It uses a fine-toothed blade held taut in a frame.
- How it Works: You push and pull the saw, and the teeth remove metal chips. The key is using the right blade.
- Blade Selection: Blades are measured by TPI (teeth per inch).
- Use 14 to 18 TPI for thick, soft metals.
- Use 24 to 32 TPI for thinner, harder metals like thin tubing or angle iron.
- Usage Tip: Always keep pressure on the push stroke. Let the saw do the work on the pull stroke (or vice versa, depending on the blade type). This is a great basic manual tool for quick tasks.
Power Tools for Cutting Metal
When manual effort is too slow or the metal is too thick, you need power tools for cutting metal. These tools use high speed or high heat to sever the material fast.
Angle Grinders and Cutting Discs
The angle grinder is one of the most versatile tools in a metalworker’s kit. When fitted with the right accessory, it becomes a powerful cutter.
Angle Grinder Metal Cutting Disc
You must use a thin, reinforced disc specifically made for cutting metal (often called cutoff wheels).
- Operation: The disc spins incredibly fast. It grinds through the metal using abrasive grit.
- Safety First: Grinders create sparks, noise, and dust. Wear full safety gear: eye protection, hearing protection, gloves, and a respirator if needed. Sparks can ignite nearby flammable materials.
- Best For: Quick cuts on thicker metal, rebar, bolts, or making shallow slots. They are excellent for cutting material that is hard to clamp down perfectly.
Portable Metal Cutting Saws
These saws look similar to woodworking circular saws but are designed for metal. They are often called portable metal cutting saw units.
Cold Cut Saws
These are specialized saws that spin a carbide-tipped blade much slower than an abrasive saw.
- Advantage: They cut metal cleanly, leaving a cool edge that needs little clean-up. This minimizes sparks and heat distortion on the workpiece.
- Ideal For: Cutting square tubing, pipe, and structural steel where precision matters.
Dry Cut Metal Saws (Ferrous Saws)
These are common and very effective for cutting ferrous metals (iron and steel).
- Mechanism: They use high-speed abrasive discs or specialized carbide blades to cut without coolant.
- Use Case: They chew through steel studs, pipe, and angle iron very quickly. The edge is hot, so handle with care.
Reciprocating Saws (Sawzall)
A reciprocating saw, often called a Sawzall (a common brand name), uses an oscillating blade motion.
- Blade Choice is Key: You need a specific metal-cutting blade, usually bi-metal with a fine tooth count.
- When to Use: They are great for demolition work or cutting metal pipes where access is tight, or when you can only cut from one side. They are generally slower and less precise than dedicated metal saws.
High-Performance Metal Cutting Technologies
For professional workshops, construction sites, or specialized fabrication, more advanced methods are used. These offer superior speed and precision for heavy-duty tasks.
Plasma Cutter for Metal
A plasma cutter for metal uses superheated, ionized gas (plasma) to melt and blow away the metal being cut.
- Speed and Thickness: Plasma cutting is incredibly fast, especially on steel, stainless steel, and aluminum. It can slice through very thick plate metal that saws would struggle with.
- Versatility: It can cut complex shapes easily, making it popular in fabrication shops.
- Setup: It requires a power source and compressed air. It is loud and creates significant heat and fumes, so ventilation is crucial.
Chop Saws (Abrasive vs. Cold Cut)
Chop saws are stationary tools ideal for cutting stock material like bars or pipes at specific angles (like 90 or 45 degrees).
- Abrasive Chop Saw: This is the most common type. It uses a large abrasive wheel, similar to an angle grinder disc. It is fast but creates many sparks and leaves a rough edge. It is a great choice among abrasive cutting tools for metal for general shop use.
- Cold Cut Chop Saw: This uses a specialized carbide blade. It cuts quietly, produces very little heat, and leaves a clean, burr-free edge, making it superior for jobs needing high accuracy.
Band Saws
Band saws are excellent shop tools for repetitive, precise cuts. They use a continuous loop blade running over wheels.
- Vertical Band Saw: Used mostly for shaping metal, cutting curves, or cutting patterns out of a flat sheet.
- Horizontal Band Saw: Used to cut raw stock material (like tubing or solid bar) to length. They hold the material securely and cut slowly and very accurately. They are quieter than abrasive chop saws.
Specific Tool Applications Based on Metal Form
The shape of the metal often dictates the best cutting method.
Cutting Sheet Metal
Thin, flat metal requires methods that prevent warping or tearing.
- Best Manual: Aviation Snips (for curves) or Straight Tin Snips.
- Best Power Tool: A jigsaw fitted with a metal-cutting blade, or an electric shear (a tool designed specifically to ‘clip’ through sheet metal quickly).
Cutting Pipe and Tubing
Pipes and tubes require cuts that are square (perpendicular to the length) or mitered (angled) for welding.
- For Accuracy (Shop): Horizontal Band Saw or Cold Cut Chop Saw.
- For Field Work (Portability): Reciprocating Saw with a fine-toothed blade, or an angle grinder metal cutting disc carefully guided against a solid square or jig.
Cutting Thick Solid Bars or Plate
When you are dealing with serious thickness, brute force and high energy are required.
- Thick Plate (Over 1/2 inch): Plasma cutter or oxy-fuel torch (if the metal is ferrous).
- Thick Bars/Rebar: Angle grinder with a thick cutoff wheel, or heavy-duty bolt cutters for smaller diameters.
Deciphering Blade and Disc Choices
The effectiveness of many metal cutting tools relies entirely on what is attached to them. Using the wrong blade or disc is dangerous and ruins the cut quality.
Hacksaw Blade Selection Chart
| Metal Type | Thickness | Recommended TPI |
|---|---|---|
| Aluminum, Brass | Thick stock | 14 TPI |
| Mild Steel | Medium stock | 18 TPI |
| Stainless Steel | Thin sheet | 24 TPI |
| Thin Tubing/Sheet | Very thin | 32 TPI |
Rule of Thumb: You should always have at least three teeth in contact with the metal at any time. Fewer teeth mean deeper penetration per stroke, better for thick material. More teeth mean a smoother cut on thin material.
Grinder Disc Specifications
When selecting a disc for an angle grinder metal cutting disc, look closely at the rating.
- Material Rating: Must say “For Metal” or “For Steel.” Do not use wood or masonry discs.
- Thickness: Thin discs (1/16 inch or 1.6mm) are for fast, clean cutting. Thick discs (1/4 inch or 6mm) are for grinding and shaping, not cutting.
- RPM Rating: The disc’s maximum safe speed must be higher than the speed of your grinder.
Safety Protocols When Cutting Metal
Cutting metal involves high speeds, sharp edges, intense heat, and flying debris. Safety is non-negotiable when using power tools for cutting metal.
Personal Protective Equipment (PPE)
Always use the following gear:
- Eye Protection: Safety glasses or a full face shield. Sparks fly often.
- Hearing Protection: Grinders and plasma cutters are extremely loud.
- Hand Protection: Leather work gloves that allow dexterity but protect against heat and sharp edges.
- Respiratory Protection: When grinding or plasma cutting, metal dust and fumes are hazardous. Use a proper particulate respirator (N95 minimum, or better for fumes).
Workpiece Security
A loose piece of metal is the most common cause of accidents.
- Always clamp the material firmly using heavy-duty vices or clamps.
- Ensure the cut-off piece (the waste material) is supported or clear so it doesn’t snag the blade as the cut finishes.
Fire Safety
Especially when using angle grinders or plasma cutters, sparks are inevitable.
- Clear the work area of all flammable materials (oils, sawdust, rags).
- Have a working fire extinguisher nearby and know how to use it.
Comparing Key Cutting Tools in Detail
Let’s compare three very common choices for general metal fabrication tasks: the angle grinder, the reciprocating saw, and the portable metal cutting saw.
| Feature | Angle Grinder (Cutoff Wheel) | Reciprocating Saw (Metal Blade) | Portable Metal Cutting Saw (Dry Cut) |
|---|---|---|---|
| Speed | Very Fast | Moderate | Fast |
| Cut Quality | Rough, leaves burrs | Rough, can wobble | Clean, minimal burrs |
| Thickness Limit | Good up to 1/2 inch | Good up to 1/4 inch (tubing) | Excellent for structural steel |
| Noise Level | High | High | Moderate to High |
| Portability | Excellent | Excellent | Good |
| Cost of Consumables | Low (Wheels wear fast) | Moderate (Blades wear fast) | High (Specialized blades last long) |
The portable metal cutting saw often wins for straight, repetitive cuts on structural steel because it balances speed, clean cuts, and portability well. However, if you need to trim a bolt sticking out in a tight spot, the angle grinder reigns supreme.
Maintenance of Metal Cutting Tools
Proper care extends the life of your tools and keeps them cutting safely.
Blade and Disc Care
- Storage: Keep blades and discs dry. Rust degrades the metal and the abrasive material.
- Blade Tension (Hacksaw): Always check the tension on a hacksaw frame before starting. A loose blade breaks easily and can cause injury.
- Disc Inspection (Grinder): Before mounting any disc, check it for chips, cracks, or signs of damage. Never use a damaged disc.
Power Tool Care
- Cleaning: Keep vents clear of metal dust. Use compressed air to blow debris out of the motor housing regularly.
- Lubrication: Follow the manufacturer’s guide for lubricating moving parts on saws and grinders.
FAQ on Metal Cutting
Can I use a wood cutting circular saw to cut metal?
No, you should not use a standard wood-cutting circular saw to cut metal. Wood blades have teeth that are too large and are designed to cut wood fibers, not hard metal. Using a wood blade on metal will quickly destroy the blade, dull it instantly, and create dangerous flying metal shards, potentially causing tool failure. Use a specialized portable metal cutting saw or a dry-cut metal saw instead.
What is the best tool for cutting thick stainless steel?
For very thick stainless steel plate, the plasma cutter for metal is generally the fastest and most effective choice. For less extreme thicknesses (up to about 3/8 inch), a heavy-duty abrasive chop saw or an angle grinder with a high-quality cutting disc can work, but be prepared for a slower cut and significant heat generation.
How do I prevent cut edges from being sharp?
Sharp edges left after cutting are called burrs. To remove them:
- Use the finest-toothed blade or disc possible for the initial cut.
- Use a dedicated deburring tool (a scraper or rounded file).
- Use an angle grinder metal cutting disc on a low setting to lightly grind the edge smooth after the cut is finished.
What is the difference between plasma cutting and oxy-fuel cutting?
Plasma cutting uses electricity to create a jet of superheated gas to melt the metal quickly, making it suitable for all conductive metals (steel, aluminum, copper). Oxy-fuel cutting uses a chemical reaction between pure oxygen and a fuel gas (like acetylene) to create a very hot flame, primarily used for cutting ferrous metals (iron/steel). Plasma is often faster and cleaner on thinner metals.