The xtool S1 Acrylic Checklist: How to Avoid Cloudy Cuts and Failed Engravings

I’ve been handling custom engraving and cutting orders for small businesses for about six years now. I’ve personally made (and documented) at least a dozen significant mistakes on acrylic jobs, totaling roughly $1,200 in wasted material and rework. After the third time I turned a sheet of beautiful, clear acrylic into a frosted, chipped mess with our xtool S1, I sat down and built this checklist. We’ve caught over 30 potential errors using it in the past year alone.

This checklist is for you if you’re using an xtool S1 (with a 10W, 20W, or 40W diode module) to cut or engrave acrylic. It’s not for industrial fiber lasers—that’s a totally different beast. We’re talking desktop laser work here. The goal is simple: get a clean, professional result without the guesswork and wasted cash.

The xtool S1 Acrylic Processing Checklist (5 Steps)

Bottom line: Follow these steps in order. Don’t skip ahead because "it looks fine." I’ve done that. It’s expensive.

Step 1: Material Verification & Prep (The Most Skipped Step)

This is where probably 50% of failures start. You gotta know what you’re working with.

1. Identify the acrylic type. This is critical. You need cast acrylic for laser cutting and engraving. Extruded acrylic will melt, produce rough edges, and can even catch fire more easily. How to tell?
   - Look for a protective paper or film label. It often says "Cast" or has a manufacturer code. If it’s gone, ask your supplier.
   - The "snap test" (carefully): Cast acrylic tends to snap cleaner; extruded is more likely to bend and stress-whiten. But honestly, just buy from a supplier who specifies "laser-grade cast acrylic."
2. Remove ALL protective layers. Both sides. Every bit. I once engraved through the film on a $85 sheet. The laser fused the plastic film into the surface, creating a permanent, bubbly, cloudy disaster. The result? The whole sheet was trash. That’s when I learned: clean material is non-negotiable. Use isopropyl alcohol to wipe off any adhesive residue after removal.
3. Check thickness with calipers. Don’t trust the label. A sheet labeled 3mm might be 2.8mm or 3.2mm. That small difference changes your focus and cut settings. Our $450 mistake was on a 50-piece order where we assumed 3mm, but it was actually 3.4mm. The cuts didn’t go all the way through, and every piece had to be re-done.

Step 2: Machine & Workspace Setup

From the outside, it looks like you just turn on the laser and go. The reality is, a dirty or unlevel machine guarantees bad results.

1. Clean the lens on your laser module. Use a lens pen or microfiber cloth with a drop of lens cleaner. A speck of dust will scatter the beam and cause fuzzy engraving or inconsistent cuts. Do this at the start of every session.
2. Level your honeycomb bed. Use the manual focus tool or a metal spacer. Place it at all four corners and the center. If the distance varies, your focus will be off across the sheet, leading to parts that are perfectly engraved and parts that are barely touched. I learned this after a two-tone map engraving job came back looking like a topographic map of the moon.
3. Install the air assist (if you have it). This isn’t optional for clear acrylic. The air assist blows smoke and molten debris away from the cut path, preventing it from re-solidifying into a cloudy, rough edge. If you don’t have the official accessory, a small aquarium pump with a tube directed near the head can help way more than nothing.

Step 3: Software & Design Pre-Checks

Your file has to be right before it ever hits "Start."

1. Convert all text to outlines/paths. If your design software (like Illustrator or CorelDRAW) uses live text, the laser software (like Laserbox or LightBurn) might substitute a font, turning "& Co." into "& C0." I’ve seen it. Embarrassing. Convert to curves/outlines first.
2. Check for duplicate lines ("doubles"). This is the silent killer. If your cut line is duplicated, the laser will pass over it twice, potentially burning too deep or even cutting through your honeycomb bed. In your laser software, use the "Select Same Color" tool to see if multiple lines are stacked. Delete the extras.
3. Set origin point and material size correctly. Make sure your design is within the actual material boundaries on your virtual workspace. I once set the origin wrong and ran a beautiful engraving… half on the acrylic and half off onto the aluminum frame. Not a good sound.

Step 4: Power & Speed Settings (The Test Is Mandatory)

Every machine, every module, every batch of acrylic is slightly different. The numbers below are a starting point, not a guarantee.

Reference - Industry Context: While industrial CO2 lasers are often the standard for acrylic, diode lasers like the xtool S1's modules work by absorption, not direct vaporization. Clear acrylic doesn't absorb the common diode wavelength (around 455nm) well, which is why you often need a backing or coating. Cast acrylic works because additives improve absorption. (Source: General laser-material interaction principles).

1. Start with a material test grid. Don’t guess. Create a small file with squares using different speed/power combinations. For a 10W module on 3mm clear cast acrylic, I’d start testing around:
   - Cutting: 100% power, speed between 2-4 mm/s (very slow).
   - Engraving (for a deep fill): 80-90% power, speed around 150-200 mm/s.
   Run the test on a scrap piece from the same sheet.
2. Evaluate the test cut.
   • Goal for cutting: A smooth, glass-like edge ("fire-polished"). If it’s rough, milky, or has melt drips ("crowns"), your speed is too high or power too low. Slow down slightly for the next test.
   • Goal for engraving: A crisp, frosted white finish. If it’s shallow or brown/burnt, adjust power up or speed down.
3. Note your winning settings. Write them down with the material brand, thickness, and module type. I keep a spreadsheet. The numbers that worked perfectly for the "PlastiCast" brand last month might need a tweak for "AcrylicPlus" this month.

Step 5: The Live Run & Post-Process

You’re almost there. Stay vigilant.

1. Do a "frame" check. Use your laser software's "Frame" function to move the laser head around the perimeter of your design without firing. Watch to ensure it stays on the material. This catches 90% of placement errors.
2. Monitor the first 30 seconds. Don’t walk away. Watch the start of the cut or engraving. Is it sparking excessively? Is the edge immediately turning brown? Hit pause. Something’s wrong—likely a setting or focus issue.
3. Post-process carefully.
   • Peel gently: If you used transfer tape as a surface protector, peel it back slowly at a 180-degree angle to avoid stressing the acrylic.
   • Clean with care: Use mild soap and water or isopropyl alcohol. Don’t use abrasive cloths or strong solvents that can scratch or haze the surface.

Common Pitfalls & Final Notes

Can the xtool S1 cut clear acrylic? Yes, but with the right type (cast) and settings. It won’t be as fast as a 100W CO2 laser, but for desktop-scale work, it’s totally viable.

The "I thought it was focused" mistake: Auto-focus is great, but always double-check with the manual tool, especially after changing material thickness. A focus error of even 0.5mm can ruin edge quality.

Ventilation is safety, not just quality: Cutting acrylic releases fumes. They’re unpleasant and potentially harmful. Use an exhaust fan vented outside. A clean cut is pointless if you’re breathing in methyl methacrylate vapor.

Prices as of early 2025 for reference: A 24" x 24" sheet of 3mm clear cast acrylic can range from $40-$80 depending on brand and supplier. Wasting one hurts. A 10W laser module for the xtool S1 is around $200-$300. Dialing in your process protects both investments.

This checklist might seem detailed, but each step is there because I, or someone on my team, learned it the hard way. It turns a finicky, sometimes frustrating process into a reliable one. Now go make something clean.