Laser or Plasma for Your Part?

The choice between laser and plasma is settled by the part, not by preference: how thick it is, what the cut edge has to do, how fine the detail runs, and whether the holes need machining as well as cutting.

Start with thickness and material

KorFab cuts sheet and plate on a 6 kW fiber laser with a 5 ft by 10 ft bed, and on a five axis plasma table with a 6 ft by 12 ft bed. The two machines do not cover the same range.

The laser's recorded range is 1/64 in to 1 in, material specific. Carbon steel is the thickest material it cuts. Stainless and aluminum cut at a reduced thickness, and copper and brass are limited to thin sheet because of how reflective they are. Galvanized steel cuts with the coating accounted for in the setup.

The plasma table cuts 1/8 in to 4 in in carbon steel, stainless steel and aluminum. Heavy plate is edge started, so the pierce limit for a given material is lower than the thickness the table can cut. That pierce limit is confirmed when we quote rather than assumed from the range.

What the cut edge has to do

If the cut edge becomes a weld preparation, five axis plasma can cut the contour bevel at an angle. Bevel angle, land and finish are confirmed per part. Laser cutting leaves a square edge, so a bevel is a separate operation after the cut.

On a part where the cut edge is only an outside profile, that difference does not matter. On a base plate or a connection part that has to assemble without extra grinding, it usually does.

How fine the detail runs

The laser holds tighter detail, smaller holes and a cleaner edge. That makes it the process for brackets, covers and enclosure parts where slots, small holes and visible edges carry the design.

Plasma carries heavy plate and large parts, where the material is thicker than the laser range or the part is larger than a 5 ft by 10 ft sheet and would otherwise be cut in pieces and joined.

What happens after the cut

The plasma table also carries a 20 HP drill head that drills, taps, counterbores and mills while the plate is still on the table. Cut features and machined features share one program, so a tapped hole pattern is positioned in the same setup as the outline instead of being re-fixtured later.

The laser etches part numbers, orientation marks and bend lines as part of the cutting program. On parts that go on to forming and welding, those marks are how a batch stays matched to its assembly.

Where the two overlap

Some parts sit between the processes. A 3/8 in plate with a simple outline and a tapped hole pattern usually belongs on the plasma table, because the machining happens in the same setup. A set of thin brackets with fine slots usually belongs on the laser, even though the plasma table could cut the outline.

We say which process we would run before quoting, rather than leaving it to be discovered after the order.

What to send with the request

• Material and thickness, not just "steel".
• Quantity, and whether the part repeats.
• What the cut edge has to do: weld preparation, visible edge, or nothing in particular.
• Hole callouts with size, thread and tolerance where they matter.
• Which dimensions are functional and which are not.
• If a bevel is needed, the angle and land you want.

If you are unsure between the two, send the drawing and describe how the part is used. The process choice is part of what the quote should tell you.