Comparison matrix of different cuting process such as waterjet, wire EDM, laser, plasma, milling, and punch.

Waterjet

Wire EDM

Plasma

Laser

Milling

Punch

Accuracy

Waterjet cutting accuracy average of ±0.003" (±0.1 mm)

Better result can be achieve with more advanced software.

Wire EDM is Extremely precise parts at ±0.0001" (±0.025mm)

Plasma cutting accuracy is in the range of ±0.030 to ±0.060"

Accuracy to ±0.001" (±0.025 mm) or better in thin material.

Very good, in the range of ±0.0003" (±0.01mm)

Fair

Thickness

Waterjet Machines mostly cut under 3" (75mm) Thicker parts can be cut with reduced accuracy and slower speed.

Very thick parts can be cut with wire EDM. Over 12" (30 cm) reported.

Plasma cutting usually cuts less than 1.25"

Usually cuts thin mild steel less than 0.25"(6.35mm)

Able to work on 3D parts.

Usually work well with thin sheets.

Cutting speed

Waterjet machine cuts five to ten times faster than EDM when thickness is under 1"

Wire EDM cuts at very Slow speed compare to waterjet (5-10 times slower)

Fast with thin sheets

Very fast cutting in thin, non-reflective materials.

Fair

Fast batch production when initial programming is done

Quality of edge

Waterjet cutter yields Good edge quality

Excellent

Fair

Excellent

Excellent

Fair

Heat affected zone (HAZ)

Waterjet produces No HAZ

Some HAZ

Some HAZ

Cuts by melting the material, resulting HAZ, often need additional process to avoid micro cracking.

No HAZ

No HAZ

Material Distortion

Waterjet machine generates No Distortion but may have hazing near the cut. No internal stress built up.

Wire EDM Cuts by melting, resulting material heat distortion.

Cuts by melting, resulting material heat distortion.

Cuts by melting, resulting material heat distortion.

No distortion

Some distortion

Other characteristics

Waterjet cutter works well in non-conductive and conductive materials.

Can pierce material directly without other drill equipment.

Fast setup and rapid programming.

Minimal requirement of fixture.

EDM is limited to cutting only conductive materials.

Relatively low capital costs. Special gas need for laser cutting.

Limited to non-reflective materials.

May need different gas for cutting different materials.

Needs special fixture and tools, also requires skilled operator and usually can not work on very large parts.

Relatively low capital costs. May need other special tools.

Not work well on on brittle or hardened materials.

Why buy waterjet machines

Waterjet cutters competes with other cutting methods with good accuracy, fast setup time and cutting speed, and yields no HAZ. 

Wire EDM shops buy waterjet machines for fast speed and to get into non-conductive materials business.

Plasma shop owners buy precision water jet cutters to cut non-conductive material or cut precision parts.

Waterjet machines typically cost 1/3 of a laser and can work on a much wider variety of materials, particularly aluminum and stainless steel over 1⁄4 to 1⁄2" (6 mm to 13 mm).

Traditional metal work shop owners acquire waterjet cutters to do metal working such as cutting large work piece with fast turn around and at setup low cost.

Punch press owners would buy waterjet cutters to improve turn around time in doing short runs and prototype parts. Also to get into cutting thinker materials.