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Atomstack A20 Pro settings for wood, acrylic and leather
Starting-point power, speed and pass settings for the Atomstack A20 Pro, a 20 W 450 nm diode machine. These are collected figures, not results from running the machine ourselves. Every machine and material batch differs — treat these as a fast start, then confirm with a material test grid.
Quick answer: on the Atomstack A20 Pro, 3 mm plywood cuts at 100% power / 300 mm/min / 2 passes, MDF at 100% / 350 / 2 passes, and opaque acrylic at 100% / 200 / 3 passes — this 20 W diode cannot cut clear or transparent acrylic (aka acrylic/perspex/plexiglass), only dark, opaque stock. Wood engraving runs at 25% power / 5000 mm/min, and 2 mm leather cuts at 85% / 500 mm/min in one pass.
Price a job on the Atomstack A20 Pro →Atomstack A20 Pro settings (power % / speed mm/min / passes)
| Material | Job | Setting |
|---|---|---|
| Plywood 3 mm | Cut | 100% / 300 / 2 passes |
| MDF 3 mm | Cut | 100% / 350 / 2 passes |
| Plywood 6 mm | Cut | 100% / 150 / 3–4 passes |
| Opaque acrylic 3 mm | Cut | 100% / 200 / 3 passes |
| Leather 2 mm | Cut | 85% / 500 / 1 pass |
| Wood | Engrave | 25% / 5000 mm/min |
| Slate / stone | Engrave | 70% / 4000 mm/min |
Clear acrylic: the Atomstack A20 Pro is a diode laser and cannot cut clear or transparent acrylic — the ~450 nm beam passes straight through. It can slowly cut dark, opaque acrylic only. For clear acrylic you need a CO2 laser.
Always: use air assist, focus for the exact thickness, and don't hold 100% power to force a cut — slow the speed or add a pass instead. Find your exact numbers with a material test grid.
All of these charts in one printable book: The Laser Settings Handbook — 18 machines, 11 material charts, the 15 fixes and a settings log in 168 pages. Read the free 13-page sample.
Get an exact price for the Atomstack A20 Pro
Settings give you the speed; the calculator turns your file's path length into machine time and cost, scaled to the Atomstack A20 Pro.
Open the Atomstack A20 Pro calculator →What an A20 Pro needs next to it
The A20 Pro is an open-frame diode, so its 455 nm beam is exposed while it works. Proper eye protection, and a bed that lets the beam leave through the bottom of the stock, matter more than any number on this page.
Safety glasses, 455 nm OD6+: Check price on Amazon ↗
Honeycomb bed: Check price on Amazon ↗
Air assist pump: Check price on Amazon ↗
Birch plywood 3 mm, laser grade: Check price on Amazon ↗
Laser-grade plywood matters on a diode: one glue void stops the beam dead and leaves a half-cut part stuck in the sheet.
Disclosure: some links are affiliate links — if you buy through them we may earn a small commission at no extra cost to you. Prices are approximate list prices at the time of writing; always check the current offer.
Bed size: what actually fits
The Atomstack A20 Pro has a working area of 400 × 400 mm (16 cm²). That decides which stock sizes you can buy without cutting them down first — the single most annoying thing to discover after the delivery arrives.
| Common stock | Size | On this machine |
|---|---|---|
| A4 sheet | 297 × 210 mm | Fits |
| 300 × 300 mm craft ply | 300 × 300 mm | Fits |
| 400 × 400 mm sheet | 400 × 400 mm | Fits |
| 600 × 400 mm sheet | 600 × 400 mm | Does not fit — cut it down first |
| 600 × 300 mm sheet | 600 × 300 mm | Does not fit — cut it down first |
Fitting parts onto the sheet efficiently is where material cost is actually won or lost. Our nesting tool takes your file and this bed size and tells you parts per sheet; the sheet yield calculator does the same from plain dimensions.
What the Atomstack A20 Pro cannot do
Knowing the hard limits saves more material than any settings tweak:
- No clear or transparent acrylic. The ~450 nm beam passes straight through it. Dark, opaque acrylic cuts slowly; clear needs a CO2 laser.
- No glass or stone engraving without help. Glass is transparent to the beam — it needs a paint or tape coating to mark at all.
- No metal cutting. Marking anodised or coated metal works; cutting bare metal does not, at any power.
- Thick hardwood is slow. Multiple passes on anything past about 6 mm, and the edge quality drops with each one.
Troubleshooting: symptom, cause, fix
| Symptom | Usual cause | Fix |
|---|---|---|
| Cut does not go through, top looks fine | Focus set for the wrong thickness, or speed too high for the pass count | Re-focus for this exact sheet, then drop speed ~25% before adding a pass. Check the back face, not the top. |
| Edges heavily charred / flaming | No air assist, or too many slow passes stacking heat | Turn air assist on — it matters more than any setting tweak on wood. Prefer fewer, faster passes. |
| Clear acrylic does nothing at all | Physics, not settings | A diode cannot cut clear acrylic. Switch to opaque stock or a CO2 machine. |
| Engrave looks washed out / grey | Power too low, or lines per cm too high for the material | Raise power in 5% steps first. On wood, 50–80 LPC is usually enough — more just costs time. |
| Lines wavy or double-struck | Belt tension or the frame flexing at speed | Check belt tension and that the gantry is square. Reduce engrave speed to confirm it is mechanical. |
If none of that helps, work through why won't my laser cut all the way through? or how to stop burn marks on wood.
Material cost per sheet
Settings tell you the time; material tells you the rest of the price. Typical cut speeds and prices per sheet for the materials this machine handles: Plywood 3 Mm · Plywood 6 Mm · Mdf 3 Mm · Leather 2 Mm · Felt 3 Mm · Cardboard 3 Mm.
To turn any of it into a quote, drop your file into the Atomstack A20 Pro calculator — it applies this machine's speeds to your actual path length. For shop pricing, the hourly rate calculator works out what your machine time is really worth.
FAQ
What power and speed cuts 3 mm plywood on the Atomstack A20 Pro?
On the Atomstack A20 Pro (20 W), a starting point for 3 mm plywood is 100% power at 300 mm/min, 2 passes. Values are starting points — run a small test on the same sheet, and use air assist for a clean edge.
Can the Atomstack A20 Pro cut clear acrylic?
No. The Atomstack A20 Pro is a diode laser (~450 nm); clear acrylic is transparent to it, so the beam passes straight through. It can cut dark, opaque acrylic slowly. Use a CO2 laser for clear acrylic.
How much does it cost to run the Atomstack A20 Pro?
Laser jobs are priced by machine time: cut length ÷ cutting speed × passes = time, then time × hourly rate + setup. Drop your file into the free calculator scaled to the Atomstack A20 Pro to get an exact time and price.
What are the Atomstack A20 Pro settings for wood?
For cutting, start at 100% power / 300 mm/min / 2 passes on 3 mm plywood, or 100% / 150 mm/min / 3–4 passes on 6 mm plywood. For wood engraving, run 25% power at 5000 mm/min. Confirm the exact numbers on a test piece first.
What are the Atomstack A20 Pro settings for acrylic?
Opaque (dark) acrylic 3 mm cuts at 100% power / 200 mm/min / 3 passes. Clear or transparent acrylic (also written acrylic/perspex/plexiglass) cannot be cut on this diode at any setting — the ~450 nm beam passes straight through it; that needs a CO2 laser instead.
What are the Atomstack A20 Pro settings for leather?
2 mm leather cuts at 85% power, 500 mm/min, in a single pass on the Atomstack A20 Pro. Use air assist to keep the edge clean, and run a test strip first since leather thickness varies by hide.