Cutting guide
Laser vs. plasma cutting
We have a plasma table, and we cut with it for many years. It's a good machine, but our fiber laser does better work on nearly every part: a cleaner edge, a tighter tolerance, and holes cut to size, so the part is closer to finished when it comes off the table. Here's how they compare, and why a laser is the better choice whenever you can get one at the same price.
The short answer
- Choose a laser whenever you can. The edge is cleaner, the holes come out to size, the part is closer to print, and there's less drilling and grinding after the cut.
- Price is plasma's one remaining advantage. Plasma machines cost less to buy and run, so on thick plate and simple shapes a plasma quote can come in lower. If a laser shop can cut the part for the same price, take the laser.
- Thickness isn't the deciding factor. How thick a machine cuts depends on its power, not on whether it's a laser or plasma. High-power fiber lasers cut 2" and more. Ours, a 6 kW fiber laser, cuts carbon steel to 1".
How each one cuts
A fiber laser focuses a beam of light to a small spot that melts the metal, and an assist gas blows the melt out of the cut: oxygen for carbon steel plate, nitrogen for stainless, aluminum, and a bright edge on thin steel. The spot is small, so the cut is narrow and the heat stays close to it.
A plasma cutter pushes gas through a constricted arc hot enough to turn it into plasma, which melts through any metal that conducts electricity. The arc is wider and carries more heat into the part, and the equipment costs less.
Laser vs. plasma, side by side
Typical figures for CNC fiber laser and CNC plasma cutting in steel. Every machine, gas, and thickness differs, so treat these as a guide, not a quote.
| What matters | Fiber laser | Plasma |
|---|---|---|
| Edge and cut quality | Smooth, nearly square edge with little or no dross | Rougher edge with a few degrees of bevel and dross on the bottom, often ground off; high-definition plasma is cleaner |
| Kerf (cut width) | Typically 0.004" to 0.020", wider in thick plate | Typically 0.040" to 0.150" |
| Heat-affected zone | Narrow: little heat goes into the part | Wider; air plasma can leave a hardened edge that is harder to drill, tap, or weld |
| Tolerance | Typically ±0.005" or better. Ours: ±0.005" standard, ±0.003" demonstrated | Typically ±0.010" to ±0.030", high-definition systems at the tighter end |
| Holes and small features | Holes down to about the material's thickness, cut to size and in place | Holes typically at least 1.5 times the thickness and slightly tapered, often drilled afterward |
| Thickness range | Set by the laser's power: high-power fiber lasers cut 2" and more in steel. Ours, a 6 kW, cuts carbon steel to 1" | Set by the system's power: production plasma also cuts 2" and more |
| Materials | Carbon steel, stainless, aluminum, brass, and copper | Any metal that conducts electricity |
| Distortion in thin sheet | Low | Higher, from the extra heat |
| Work after the cut | Little: holes to size, square edges, little dross | Often drilling holes and grinding dross and bevels |
| Price | Typically lower on sheet and detailed parts | Can be lower on thick plate and simple shapes, because the machines cost less: plasma's one remaining advantage |
Industry figures are typical ranges, not measurements of any one machine. Texas Laser Services figures are our own, as stated on our quality page.
Cost by thickness
A laser makes the better part in nearly every case. What changes with thickness is how close plasma's price gets. Typically:
| Carbon steel thickness | Our advice | Why |
|---|---|---|
| Sheet, up to 3/16" | Laser | Faster and cleaner, with less warping. Plasma puts more heat into thin sheet and leaves dross to clean off. |
| 1/4" to 1" | Laser | Holes come out to size and edges come out square, so the part needs no drilling or grinding. Our laser cuts carbon steel to 1". |
| Over 1" | Laser, from a shop with a high-power fiber laser | High-power fiber lasers cut 2" and more. Here plasma's lower machine cost shows most in the quote, so compare prices; if they're the same, take the laser. |
Compare the whole price, not just the cut. A plasma part that needs its holes drilled and its edges ground can cost more than a laser part that is finished when it comes off the table.
Is plasma ever the better choice?
Only on price. Plasma machines cost far less to buy than lasers, so on thick plate and simple shapes a plasma shop can sometimes quote less.
If a laser shop can cut the part for the same price, take the laser. You get a cleaner edge, holes to size, a part closer to print, and less work after the cut.
Why a laser is the better choice
- Tighter tolerances, and parts that match a print and an inspection report.
- Bolt holes, slots, and small features cut to size and in place, so there's no drilling.
- Clean, square edges with little dross, in carbon steel, stainless, and aluminum.
- Less heat and warping, most of all in sheet metal.
- Blanks that bend accurately, and tab-and-slot parts that fit together for welding.
- Repeat production runs, where every part has to match the last.
Why send your laser work to Texas Laser Services
- ±0.005" standard tolerance, ±0.010" routine across our whole material range, and ±0.003" demonstrated in production runs.
- Thickness: carbon steel to 1", stainless to 3/4", aluminum to 5/8", brass to 9/16", and copper to 1/4" on our 6 kW fiber laser.
- Measured to your print on a Keyence image dimension measurement system, with mill certs traced to the parts we ship when you need them.
- A quality system certified to ISO 9001:2015, with our on-time, first-pass yield, and uptime figures published live.
- Bending, welding, threading, and powder coating in the same shop, so cut parts don't wait on another supplier.
- Shipped across the US from our shop in Santa Anna, Texas.
Comparing a waterjet too?
A waterjet cuts cold, so it leaves no heat-affected zone, and it cuts stone, glass, and composites a laser can't. It's also slower and costs more per part in most metal. Read our guide to laser vs. waterjet cutting.
Laser vs. plasma questions
Is laser cutting better than plasma?
For nearly every part, yes. A laser cuts a cleaner, squarer edge, holds a tighter tolerance, and cuts holes to size, with less heat in the part. The only thing plasma has left is price, and only sometimes. If a laser shop can cut your part for the same price, choose the laser.
Is laser cutting more accurate than plasma?
Yes, typically. A fiber laser commonly holds ±0.005" or better, while CNC plasma typically holds ±0.010" to ±0.030", with high-definition systems at the tighter end. Our standard is ±0.005", and we've held ±0.003" in production runs.
Is plasma cutting cheaper than laser cutting?
Sometimes, on thick plate and simple shapes, because plasma machines cost less to buy. On sheet metal and parts with holes or small features, a laser is often cheaper, because the part needs no drilling or grinding afterward. Compare the whole price, and if it's the same, take the laser.
Can a laser cut as thick as plasma?
Yes, if it's powerful enough. How thick a machine cuts depends on its power, for lasers and plasma alike, and high-power fiber lasers cut 2" and more in steel. Ours, a 6 kW fiber laser, cuts carbon steel to 1".
Can bolt holes be cut instead of drilled?
On a laser, yes: holes come out to size and in place. As a rule of thumb, a laser cuts clean holes down to about the material's thickness in steel. Plasma holes are typically tapered and larger, so they're often drilled afterward.
Which edge is better for welding and painting?
Laser edges are narrow in heat and nearly square, so parts fit up well. Oxygen-cut carbon steel carries a thin oxide layer on the edge, and nitrogen-cut edges are bright. Air plasma can leave a hardened edge that may need grinding before it welds cleanly. Tell us if your parts are going to be welded, painted, or powder coated.
Do you offer plasma cutting?
No. We have a plasma table and cut with it for many years. It's a good machine, but the fiber laser does better work on nearly every part, so we quote laser cutting: carbon steel up to 1", stainless to 3/4", and aluminum to 5/8".
Have a drawing ready? We'll quote it.