How Thick Can a Diode Laser Cut? Reading Official Depth and Pass Data
Key takeaways
- Record first-pass breakthrough, usable cutting, and stable production thickness separately.
- Wood species, glue layers, moisture, color, focus, air assist, speed, and pass count all change cutting depth.
- The table below organizes A70 Max cutting starting points and clearly separates single-pass, multi-pass, and production verification.
- For thick sheets, compare total time, success rate, and rework at an acceptable edge quality—not maximum thickness alone.
“How thick can a 70W laser cut?” sounds like a single-number question, but it includes at least nine variables: material type, density, glue layers, color, moisture, focus, air-assist flow, speed, and number of passes. Maximum-depth claims cannot be compared directly when the test conditions are different.
The practical answer is to ask whether a specific sheet can be cut reliably within your acceptable edge quality and processing time. A one-time limit reveals power potential; stable production thickness determines whether orders ship on schedule.
A single pass and multiple passes are not the same metric
A single-pass cut breaks through after the head follows the path once. A multi-pass cut repeats the path at the same focus or at progressively lower focus positions. Multiple passes may increase total depth, but they also increase processing time, charring, taper, and fire risk.
Use three result levels:
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First breakthrough:the sample just separates; this does not mean the edge is sale-ready.
- Usable cut:more than 90% of the contour releases without force, and rear residue and darkening meet your written quality standard.
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Stable production: repeat the same material batch, define allowable charring, taper, rework, and total time in advance, then judge every sample by the same standard.
Start with the A70 Max material settings
If you use A70 Max, begin with our official A70 Max material parameters. For 15mm basswood, start at 300mm/min, 90% power, and 1 pass. Wood density, moisture, and glue layers vary by batch, so run a coupon from the same sheet before committing to production.
| Material | Thickness | Speed | Power | Passes | Recommended use |
| Basswood | 15mm | 300mm/min | 90% | 1 | Single-pass starting point |
| Basswood | 20mm | 1,200mm/min | 90% | 10 | Multi-pass route; not directly comparable with the 15mm single pass |
| Pine | 20mm | 120mm/min | 90% | 1 | Single-pass starting point |
| Pine | 25mm | 1,100mm/min | 90% | 10 | Multi-pass route |
| Paulownia | 18mm | 350mm/min | 90% | 1 | Single-pass starting point |
| Paulownia | 20mm | 800mm/min | 90% | 2 | Two-pass route |
| Acrylic | 8mm | 100mm/min | 90% | 1 | Test the same color and grade first |
| Acrylic | 26mm | 100mm/min | 90% | 10 | Multi-pass testing; watch heat and edge quality |
| MDF | 9mm | 200mm/min | 90% | 1 | Single-pass starting point |
| MDF | 12mm | 1,000mm/min | 90% | 6 | Multi-pass route |
For medium-size engraving and cutting, A40 Pro V2 combines selectable 48W/24W power with a compact 385×400mm work area. When large layouts and medium-thick sheets become the bottleneck, A70 Max offers selectable 70W/35W and an 850×800mm work area. Time the same core SKU from setup through cleanup before choosing the configuration that fits your orders.
Air assist changes more than smoke
Air assist moves smoke and hot gases out of the kerf, helping energy reach the cut while reducing lens contamination and surface charring. More airflow is not always better: light material may shift, and excessive flow can enlarge a flame or disturb small parts.
Run an A/B test on the same sheet with the same focus, speed, and power, changing only air assist. Record top-side char width, rear breakthrough, taper, edge color, flame duration, and lens contamination. Note the pump's rated airflow and nozzle distance with the result.
Build your own cutting-depth chart in four steps
Step 1: Lock the material identity
Record supplier, species or polymer type, thickness tolerance, batch, and moisture. For plywood, also record ply count and bonding structure. Two sheets with the same name can still behave very differently.
Step 2: Run a speed ladder first
Start from a safe range near the manufacturer recommendation and cut short lines or small squares on scrap. Hold power and air assist constant, change only speed, and narrow the range after finding settings that break through without excessive charring. Do not start with an extreme test on a finished sheet.
Step 3: Compare passes and focus
For thick sheets, record whether each pass keeps the same surface focus or uses automatic step-down. Compare fixed focus with progressive focus for taper, time, and success rate. Keep the lens clean and the sheet flat or the data will not be comparable.
Step 4: Validate with repeat samples
Repeat each setting at least 3 times. Record failures instead of photographing only the best result. Publish “fastest breakthrough” and “stable production” as separate values.
Scene illustration: Separate coupons for wood, acrylic, and MDF make it easier to build settings for your own material batches.
Why the same setting may fail on your sheet
Moisture, glue, knots, density, and actual thickness all change absorption and exhaust behavior. Instead of assuming an unsupported variation percentage, record the minimum, maximum, failure count, and edge quality for the batch. That evidence shows whether a setting is ready for production.
Conclusion
If your business frequently cuts thick wood and thick colored acrylic, compare high-power machines by total time and rework under stable production conditions. If most work is thin sheet, lettering, and occasional cutting, a selectable-power machine such as A40 Pro V2 may offer a better balance. For thick-sheet work, start from the official A70 Max material parameters, then build production settings with your own stock.
FAQ
Q1: Will more passes always cut thicker material?
A: No. More passes also increase time, charring, taper, and fire risk. A setting is production-ready only when edge quality, success rate, and total time all meet the target.
Q2: Why do plywood sheets of the same thickness cut differently?
A: Species, glue, voids, knots, moisture, and actual thickness can differ. Record supplier and batch.
Q3: How do I build my own depth chart?
A: Lock the material identity, run a speed ladder, compare passes and focus, and finally record repeat samples against one acceptance standard.
