Cutting metal is an essential process across many manufacturing industries. Traditionally, metals were cut manually using saws, shears, oxy-fuel torches, and other basic tools. However, these manual methods tend to be slow, inconsistent, hazardous, and labor-intensive. Using machine cutters provides major advantages in efficiency, precision, speed, safety, and cost-effectiveness.
Overview of Metal Cutting Methods
There are several main types of machine cutters used in industry:
- Milling machines use rotary end mills and similar cutting tools to machine metals. Milling can achieve very precise and complex cuts. It is versatile for prototype work but slower for high-volume production.
- Laser cutters focus a high-power laser beam to melt/vaporize material. Laser cutting is very accurate with small kerf widths, allowing close nesting of parts. It can cut delicate patterns in thin sheets.
- Plasma cutters use a constricted arc of ionized gas heated to over 20,000°F. The high temperatures melt and displace material. Plasma can cut any electrically conductive metal quickly and in thicker ranges than laser.
- Waterjet cutters direct an ultra-high pressure stream of water mixed with abrasive particles. Waterjets offer cool cutting, no heat-affected zones, and the ability to cut highly reflective materials.
Each method has its strengths based on the metal type, thickness, required precision, and production volumes. Combining multiple methods is common for an optimized, cost-effective process.
Key Factors for Efficient Metal Cutting
Several key factors influence cutting efficiency and should guide machine selection and setup:
Material composition and thickness fundamentally impact the cutting process. Materials like stainless steel require more force and generate higher heat compared to aluminum. The material’s thermal conductivity determines how quickly heat dissipates from the cut zone.
Thicker materials require more cutting power. Each machine has an optimal thickness range based on its cutting mechanism. Going outside this range risks slow cuts or quality issues. For very thick metals, multiple passes may be necessary to achieve full penetration.
Cut Quality Standards
The level of cut quality and precision needed is another essential consideration. Laser and plasma cutters produce narrower kerf widths and more precise edges compared to other methods. Waterjet cut edges have a rougher finish.
If minimal post-processing is desired, lasers offer superior cut quality for thin gauge sheets. Evaluating acceptable tolerances and edge finishes for the application focuses the machine selection.
Production environments demand high cutting speeds to maximize workflow efficiency. Milling machines offer the slowest metal removal rates in most cases, while plasma and laser cutters achieve much faster cuts.
Optimizing feeds and speeds is crucial, especially for milling tools. The cutter should be fed fast enough to avoid excess heat generation while not overloading its capacity. Flood coolant is strongly recommended.
Operating Costs & Production Volumes
The operating costs and production volumes for current and forecasted work should be analyzed when selecting a cutting method. Milling machines and laser cutters involve higher capital costs but allow very precise and flexible cuts.
Plasma systems have become extremely cost-effective for mid to high production volumes. Consumable parts life, energy consumption, and maintenance costs are also considerations.
Automation & Software Integration
Modern machine cutters provide options for automation and software integration for additional efficiency gains. This includes support for CAD/CAM programming, tool libraries, nesting software, and machine monitoring.
Some systems can self-adjust parameters during cutting to maintain edge quality. Integrated part sorting, material handling, and robotic loading/unloading are also available.
Best Practices for Optimized Cutting
Properly setting up and operating metal cutting machines is equally important for efficiency. Follow these best practices:
Secure Proper Fixturing
The workpiece must be firmly secured in all axes to prevent vibration or shifting during cutting. Jigs and fixtures should locate parts precisely and clamp them adequately to withstand cutting forces. Insufficient fixturing causes inaccurate cuts, reduced tool life, and unsafe conditions.
Select Suitable Cutting Tools/Consumables
Match the cutting tools to the operation, material, and machine capabilities. For milling, use end mills designed for high efficiency metal removal whenever feasible. If laser or plasma cutting, choose nozzles and gases to match material type and thickness.
Sharp cutting tools are essential. Set schedules and replacement criteria to ensure blades, nozzles, and filters are maintained properly. Consider tool coatings to boost longevity.
Optimize Cutting Parameters
The feeds, speeds, power settings, etc. have a massive impact on cutting efficiency and quality. Conservative parameters waste time and tool life while overly aggressive ones risk tool failure or poor edge quality.
Fine-tune settings through test cuts on actual production materials. Many machines have onboard optimization cycles to dial in parameters. Reference tooling supplier recommendations as a starting point.
Use Proper Chip & Slag Removal
Efficient chip evacuation is critical, especially for milling machines. Chips can jam and break cutting tools. Use flood coolant or air blasts along with angled chip breaker designs. For thermal cuts, slag buildup also hinders cuts and risks damage to parts or machines.
Perform Preventative Maintenance
A well-maintained machine cuts faster and more accurately. Replace worn components before they fail. Clean guides, tracks, and motors regularly. Lubricate slides and ballscrews. Software can track machine usage and prompt for routine maintenance.
Implementing machine cutters for metal fabrication unlocks immense productivity and quality gains compared to manual cutting. Each main cutting method offers unique benefits depending on the material, precision needs, operating costs, and production volumes.
By studying these key factors and following best practices around machine setup, fixturing, tool selection, parameter optimization, chip/slag control, and preventative maintenance, manufacturers can achieve highly efficient and cost-effective metal cutting. Reach out to vendors to trial equipment and get personalized recommendations. The result is faster lead times, reduced labor, and higher quality finished components.