xTool S1 Settings for Acrylic: A 5-Step Checklist to Avoid Wasted Material and Time

Let me be upfront: I test laser systems for a living, and I’ve watched more acrylic sheets crack, bubble, or flame up than I’d like to admit. I’ve seen the same mistakes in shops using an xTool S1—especially when someone’s in a rush trying to meet a deadline.

This isn’t a theory article. This is the checklist I use when I’m on-site or handling tech support for shops that run laser projects. If you’re setting up your xTool S1 for acrylic and want to avoid wasting material—this is for you.

Here’s the 5-step process I follow. It’s not complicated, but skipping even one step can cost you a piece of acrylic and an hour of frustration.

Step 1: Confirm Your Acrylic Grade – Standard or Cast?

This is the #1 mistake I see. People buy “acrylic sheets” online and assume all acrylic is the same. It’s not.

There are two main types for laser work:

• Standard (extruded) acrylic: Softer, easier to cut, produces a flame-polished edge. This is what you want for cutting.
• Cast acrylic: Harder, better for engraving detail. For cutting? Avoid it—unless you like 50% scrap rates and looking like you’re melting jelly.

Check the label on your acrylic sheet. If it doesn’t specify, assume it’s cast. I learned that one in 2023 when a $200 batch of clear acrylic turned into a warped disaster. The client’s alternative was to cancel the order for a trade show. Not great.

Quick test: Try flexing the corner. If it bends easily, it’s likely standard. If it’s rigid with a sharp snap, it’s cast. Use cast for engraving only.

Step 2: Set Your xTool S1 Power and Speed (Don’t Guess)

Most people start with “high power, slow speed” and get charred edges. The xTool S1 has a 10W, 20W, or 40W module. For 3mm standard acrylic (the most common size for plaques and signage), here’s my go-to:

• 20W module: Power 85%, Speed 10 mm/s, 1 pass
• 40W module: Power 70%, Speed 20 mm/s, 1 pass

If you’re doing engraving on cast acrylic, switch to Power 40%, Speed 100 mm/s, 1 pass. You want to frost the surface, not burn through it.

The surprise for me? Lower power often gives a cleaner edge on acrylic. I was convinced more power = better cut. The opposite is true—too much heat cracks the sheet. I had to redo a batch of keychains before a client visit because I cranked it to 100% power. Never expected that.

Always start with a test piece. I keep a 10×10 cm scrap just for this. If I could go back, I’d tell myself on day one: “No project acrylic cutting starts until you test the scrap.”

Step 3: Factor in Material Thickness – It’s Not Linear

This is the point where many get confused. If 3mm works at Speed 10, 5mm doesn’t mean Speed 6. It’s often two passes.

Here’s a rule from my own records:

• 3mm: 1 pass at 85% power, Speed 10 mm/s (20W module)
• 5mm: 2 passes at 85% power, Speed 8 mm/s (20W module)
• 6mm: 3 passes at 85% power, Speed 6 mm/s, but honestly you’re pushing the limit with a diode laser. A CO₂ is better here if you can afford it.

The trick is to let the material cool between passes. I set a 5-second delay between passes in LightBurn. Without that, heat buildup still causes cracking.

Important note: Don’t exceed 6mm with a diode laser on acrylic. I see forum posts asking about 10mm cuts. You might get through, but the edges will be rough, and you risk fire. Not worth it.

Step 4: Use Proper Air Assist (Non-Negotiable)

I can’t overstate this. Acrylic produces flammable fumes when laser-cut. Without air assist, you risk flash fires. I’ve seen it happen—not at my shop, but at a friend’s facility in April last year. They lost a piece and had a burn mark on the honeycomb bed. Scary stuff.

The xTool S1’s air assist kit is worth every penny. I’d consider it mandatory for acrylic. If you don’t have one, stop reading and get it. The cost of a fire alarm call-out is higher than the accessory.

An air pressure of 30–45 L/min is ideal for acrylic. Blow the fumes away and keep the cut zone cool. Also: always verify ventilation. Even with air assist, I run an exhaust system and keep a fire extinguisher nearby during jobs. I’d rather be careful than sorry.

Step 5: Check Your Focal Point – Don’t Assume It’s Correct

This sounds obvious, but about one in four machines I service has the focus set wrong. The xTool S1 uses a fixed focus length (usually 4 mm from the laser head). If you’re using thick material or a rotary attachment, the distance changes.

My method: use a ramp test (a scrap of acrylic at an angle) to find the sharpest line. Or just use the included focus gauge. It’s free and takes 10 seconds. I do this every time I switch material thickness.

A 1 mm focus error can reduce cut quality by 50%—from smooth to edge that feels like sandpaper. I wasted a whole set of acrylic coasters once because I forgot to re-focus after cleaning the lens. Not fun.

Post-decision doubt: Even after setting up my focus, I sometimes wonder “did I get it right?” until I see the first test piece. That moment of hesitation happens every time, but the test never lies.

Common Mistakes and Extra Tips

• Don’t skip the masking film: Acrylic comes with a protective film. Remove it after cutting, not before. It protects against residue and scratches.
• Watch for bubbles: If your cut looks like foam, you’re going too slow or too hot. Raise speed or lower power.
• Keep a flame-polish trick in mind: For a glass-like edge on standard acrylic, use a fine flame torch carefully. But honestly, the xTool S1 already does a decent job with proper settings.
• Material cost is part of the TCO: The acrylic sheet might cost $15, but if your settings waste one, that’s $15 plus your time. I’ve seen people burn through $200 in material in an afternoon because they skipped testing. The $500 machine suddenly becomes $700 in lost materials.

So glad I switched to a dedicated test piece policy early on. Almost skipped it once to save 5 minutes, which would have meant redoing an entire job. Dodged a bullet.

That’s the checklist. Five steps: grade, power/speed, thickness, air assist, focus. Follow them, and you’ll get clean, consistent results with your xTool S1 on acrylic. I still keep this list taped to my workbench.