Atomstack A20 Pro laser settings — wood, acrylic, leather, metal and more
The Atomstack A20 Pro runs a 20W optical output diode laser — the same module used in the X20 Pro and S20 Pro. That means community settings found for those machines transfer directly to the A20 Pro, and there's a large pool of tested data to draw from. This guide covers the most common materials with starting settings that work in LightBurn, plus notes on what to watch for with each material.
All speeds are in mm/min unless noted. Air assist is the F30 or F60 kit — strongly recommended for any cut operation. These are starting points: run a test piece on scrap before committing to a full batch, since material batches vary.
Wood settings
Wood is where the A20 Pro's 20W output makes the biggest practical difference. Basswood and thin birch plywood cut in a single pass at reasonable speeds — something a 10W machine can't reliably do.
| Material | Operation | Speed (mm/min) | Power | Passes | Air assist | Notes |
|---|---|---|---|---|---|---|
| 3mm Basswood | Cut | 300 | 90% | 1 | Yes | Pin flat. Air assist keeps cut clean. |
| 3mm Basswood | Engrave | 3,000 | 20% | 1 | No | Line interval 0.1mm. Official Atomstack table. |
| Basswood (general) | Cut | 3,000 | 80% | 1 | Yes | Single pass, clean edge. |
| 3mm Baltic Birch | Cut | 250 | 100% | 3 | Yes | Glue layers vary — 3 passes for consistency. |
| 3mm Baltic Birch | Engrave | 2,000 | 40–45% | 1 | No | 254 DPI for general engraving. |
| 3mm MDF | Cut | 200 | 100% | 2 | Yes | Air assist essential — MDF smokes heavily. |
| 3mm MDF | Engrave | 2,000 | 40–45% | 1 | No | 254 DPI. |
| Bamboo Cutting Board | Engrave | 2,500 | 60% | 1 | No | Line interval 0.1mm. Excellent contrast. ★ Verified |
| Bamboo 3mm | Cut | 1,800 | 82% | 3 | Yes | Air assist essential. |
| Maple / Walnut | Cut | 1,800 | 90–100% | 4 | Yes | Hardwood needs slow multi-pass. |
| Maple / Walnut | Engrave | 5,000 | 65–75% | 1 | Yes | 254 DPI. |
MDF is the hardest wood material on the A20 Pro. It contains glue binders that resist the diode laser more than natural wood. Use air assist, go slow, and don't skip passes — an under-cut piece that shifts between passes will ruin the job. Pin the sheet flat with hold-down clips before you start.
See all A20 Pro wood settings →Acrylic settings
Acrylic is workable on a 20W diode but requires more passes than a CO2 laser. Cast acrylic performs significantly better than extruded — it cuts cleaner and doesn't melt the same way. If you're buying acrylic specifically for laser work, get cast.
| Material | Operation | Speed (mm/min) | Power | Passes | Notes |
|---|---|---|---|---|---|
| 3mm Clear Acrylic | Cut | 700 | 100% | 4 | Air assist. Diode needs slow multi-pass. |
| 3mm Clear Acrylic (Cast) | Cut | 2,200 | — | 1 | Cast cuts cleaner than extruded. |
| 3mm Clear Acrylic (Cast) | Engrave | 4,500 | — | 1 | 254 DPI. Frosts to white. |
| 3mm Mirrored Acrylic | Engrave | 4,200 | — | 1 | 254 DPI. Engrave from the back side for clean mirrored result. |
Ventilate whenever cutting acrylic — diode lasers tend to melt rather than vaporize the edges at lower speeds, which produces more fumes than a CO2 cut. Air assist helps push fumes away from the beam and keeps the cut channel clear.
Leather settings
Leather engraves beautifully on the A20 Pro. Veg-tan is the standard choice — chrome-tanned leather releases toxic fumes and should not be lasered. Ventilate well regardless. The 20W module gives enough power to cut thick leather cleanly in two passes.
| Material | Operation | Speed (mm/min) | Power | Passes | Notes |
|---|---|---|---|---|---|
| Faux Leather | Cut | 3,500 | 58% | 1 | Air assist recommended. |
| Faux Leather | Engrave | 8,000 | 20–25% | 1 | 254 DPI. Fast light pass. |
| Genuine Leather | Engrave | 3,000 | 30% | 1 | Line interval 0.1mm. Veg-tan only. |
| Veg-Tan Leather ~3mm | Cut | 2,500 | 85–95% | 2 | Air assist. Ventilate well. |
| Veg-Tan Leather ~3mm | Engrave | 6,000 | 60–70% | 1 | Air assist. Clean burn on grain side. |
| Leather (general) | Cut | 1,500 | 100% | 2 | Ventilate. Leather fumes are strong. |
| Leather (general) | Engrave | 4,000 | 50% | 1 | Grain side only. Flesh side gives rough result. |
For tumblers and cylindrical leather pieces, you need a rotary attachment. The A20 Pro supports most Y-axis rotary setups. Disengage the Y motor, connect the rotary, set the correct diameter in LightBurn (Object > Rotary Setup), and run a calibration square before your first job.
Metal settings
A 20W diode laser cannot cut metal, but it can engrave coated metals, anodized aluminum, and powder-coated surfaces cleanly without any marking spray. For bare stainless steel, you need Cermark, Molybdenum spray, or similar marking compound — the diode beam won't mark bare metal without it.
| Material | Operation | Speed (mm/min) | Power | Passes | DPI | Notes |
|---|---|---|---|---|---|---|
| Anodized Aluminum | Engrave | 2,000 | 60–75% | 1 | 300 | Ablates dye layer. No coating needed. |
| Anodized Aluminum | Engrave | 1,500 | 70–80% | 1 | 400 | Higher DPI for fine text and logos. |
| Anodized Aluminum | Engrave | 4,000 | 55% | 1 | — | Line interval 0.1mm. Standard community setting. |
| Powder Coated Steel | Engrave | 2,500 | 80% | 1 | 254 | Ablates coating to reveal bare metal. Clean with IPA first. |
| Powder Coated Tumbler | Engrave | 2,500 | 65–75% | 1 | 300 | Use rotary. Test on scrap tumbler first. |
| Powder Coated Tumbler | Engrave | 2,000 | 70–80% | 1 | 400 | Fine detail / photo on tumbler. |
| Stainless Steel (bare) | Mark | 400 | 90–100% | 1 | — | Apply Cermark or Molybdenum spray first. |
| Stainless Steel (bare) | Mark | 500 | 80–95% | 1 | — | Wash residue with water after. |
| Spray Painted Metal | Engrave | 2,800 | 75% | 1 | 254 | Thinner than powder coat — reduce power if paint splatters. |
Black powder coat gives the highest contrast result when engraved. The laser ablates the coating to expose the bare metal beneath, creating a sharp two-tone look. Clean the surface with isopropyl alcohol before engraving — any oil or residue scatters the beam and creates uneven marks.
See all A20 Pro metal settings →Stone and glass settings
Slate and marble are excellent materials for the A20 Pro. The diode wavelength ablates stone surface cleanly, creating high-contrast white marks on dark stone. Glass is possible but requires a masking technique to reduce micro-fracturing.
| Material | Operation | Speed (mm/min) | Power | Passes | DPI | Notes |
|---|---|---|---|---|---|---|
| Slate | Engrave | 4,000 | 55% | 1 | — | Line interval 0.1mm. Clean ablation. |
| Slate Coaster | Engrave | 5,000 | 70–80% | 1 | 254 | Standard coaster setting. |
| Slate Coaster | Engrave | 2,200 | 90% | 1 | 400 | Fine detail / photo work on slate. |
| Slate Coaster | Engrave | 1,800 | 85–90% | 1 | 300 | Denser ablation — wipe clean after. |
| Marble Tile | Engrave | 2,200 | 85% | 1 | 254 | High power for frosted result. |
| Marble Tile | Engrave | 1,500 | 80–85% | 1 | 300 | Lower power than slate — start here. |
| Glass | Engrave | 7,000 | 60–70% | 1 | 254 | Mask with wet tissue to reduce fracturing. |
| Glass | Engrave | 1,200 | 45–55% | 1 | 300 | Slower for finer detail. |
| Glass | Engrave | 1,000 | 55% | 1 | 400 | Fine detail — mask surface first. |
For glass, apply masking tape or lay wet newspaper directly on the surface before engraving. The moisture absorbs heat and reduces the micro-fracturing that gives glass engravings a rough, crumbled appearance. Remove the masking and wipe clean after the job.
Slate coasters are one of the best-selling laser products on Etsy and one of the most beginner-friendly materials on the A20 Pro. The stone doesn't warp, doesn't require air assist, and produces high-contrast marks with very little trial and error. If you're new to the A20 Pro, slate is a good first material to dial in.
Other materials
| Material | Operation | Speed (mm/min) | Power | Passes | Notes |
|---|---|---|---|---|---|
| Cork 3mm | Cut | 5,000 | 45% | 1 | Air assist on. Single pass. |
| Cork 3mm | Engrave | 3,000 | 30% | 1 | 254 DPI. Keep power low — cork chars easily. |
| Cardboard | Cut | 800 | 50% | 1 | Air assist on. |
| Cardstock | Cut | 1,500 | 35% | 1 | Single clean pass. |
| EVA Foam 6mm | Cut | 4,500 | 45% | 1 | No air assist — foam can move. |
| Mylar Stencil 7.5mil | Cut | 7,000 | 25% | 1 | Fast accurate single pass. |
| HTV Vinyl | Cut | 9,000 | 16% | 1 | Light score — not full depth cut. |
| Rubber Stamp | Engrave | 2,800 | 82% | 1 | 300 DPI. Invert design before engraving. |
| Cotton Fabric | Cut | 2,000 | 35–40% | 2 | Air assist. 2 passes for clean edge. |
| Cotton Fabric | Engrave | 7,000 | 22% | 1 | 254 DPI. Light fast pass. |
LightBurn tips for the A20 Pro
The A20 Pro connects over USB to LightBurn as a GRBL device. Use the Atomstack device profile if available, or enter the work area manually (400 × 400 mm for the standard model, 400 × 850 mm for the extended Y-axis version).
Set your speeds in mm/min in LightBurn — the A20 Pro's GRBL firmware uses mm/min natively. If you see settings in mm/s elsewhere, multiply by 60 to convert (e.g. 50 mm/s = 3,000 mm/min).
For photo engraving, use Jarvis or Stucki dithering in LightBurn's Image Mode settings. Set DPI to 254 as a starting point, then increase to 300–400 for fine portrait work. Run at moderate speed (2,000–4,000 mm/min) with power around 40–60% depending on material.
Always run a framing pass (press the Frame button) before engraving to confirm alignment. The A20 Pro's open frame means the workpiece can shift slightly if the honeycomb bed isn't level. Pinning material flat before framing prevents misalignment on long runs.
Browse the full A20 Pro settings library →Affiliate links - we may earn a small commission at no extra cost to you.
"Used it with a Glowforge — engraved beautifully with no changes. I will be purchasing more digital downloads from this shop."
— Anna
"I was struggling with lining up my NFC business cards. I was able to not only line them up much better but also do multiple cards at once — making that job so much easier."
— Camp
"Excellent quality and design. Cut clean and neat!"
— LYNN
"Great jigs. Appreciate the time saved not having to build this from scratch!"
— Bruce
"Excellent quality. Item as described. Expectations exceeded."
— Michael
"This template made my slate coasters so much easier. 4×4 coasters from Michaels drop in easily and are easy to remove. Def worth it."
— chris