20 W diode settings: cast acrylic, clear, 3 mm
Quick answer
A 20 W diode can neither cut nor engrave cast acrylic, clear at 3 mm. Clear acrylic is transparent at 445 nm, so a diode laser cannot cut it at any power. This is a property of the material, not a limit of the machine.
Community starting points, not manufacturer specifications. Optical power, lens, air assist and the stock itself all shift these. Test on offcuts of the same sheet before committing a real workpiece.
| Operation | Power | Speed | Passes |
|---|---|---|---|
| Cut through | Not achievable | Not achievable | - |
| Engrave surface | Not achievable | Not achievable | - |
Read these as a starting point, not a specification
No machine maker publishes settings for third party stock, so every figure on this page is a community starting point gathered from tested profiles. Optical power varies between machines sold at the same rating, lens focal length changes the spot size, and air assist changes the result more than most people expect.
Plywood deserves a specific warning. It varies between sheets and even within one sheet, because the glue layers inside are not uniform, so a setting that cut cleanly yesterday may leave an uncut patch today. Always run a small test cut on an offcut from the same sheet before committing a real workpiece.
Why this machine cannot cut it
Clear acrylic is transparent at 445 nm, so a diode laser cannot cut it at any power. This is a property of the material, not a limit of the machine.
Publishing a number here would imply it works. It does not, and the honest answer is to move to a more capable machine class or pick a material and thickness this one suits.
20 W diode machines and air assist
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ATOMSTACK Swift 12000mW Laser Engraver & Cutter for Beginners
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Safety
Common questions
Can a 20 w diode cut cast acrylic, clear?
No. At 3 mm this is beyond what a 20 w diode can do, and clear acrylic is transparent at 445 nm, so a diode laser cannot cut it at any power. This is a property of the material, not a limit of the machine.. Use a more capable machine or choose a material this one suits.
What does percentage power mean here?
It is a percentage of the machine rated optical output, not its electrical draw or its marketing wattage. A machine advertised as 80 W might deliver 20 W of optical power from four diodes, and the percentage applies to that 20 W. Comparing settings between machines only works when you know the real optical figure for each.
Do I need air assist for this?
For cutting it is the single largest quality improvement available, because it clears smoke from the lens and debris from the kerf so each pass reaches fresh material. For engraving it matters less but still protects the optic and keeps power consistent through a long job. Settings published without air assist rarely transfer to a machine that has it, or the reverse.
Why did the same settings work last time and not today?
Material variation is the usual answer, especially in plywood where internal glue layers are uneven. Beyond that, a lens with smoke residue on it loses real power, and focus that has drifted by a fraction of a millimetre widens the spot enough to stop a marginal cut working. Clean the lens and re-check focus before changing the settings.