The 7-Point Quality Inspector's Checklist for Perfect Acrylic Cuts on the xTool S1

Who This Checklist Is For

This is for you if you own an xTool S1 (20W or 40W model) and you've had at least one acrylic cut go wrong, or if you're new to cutting and want to skip the trial-and-error phase. I'm the quality/brand compliance manager at a small laser design company. I review every finished piece before it reaches our clients—roughly 200 unique items annually. In Q1 2024 alone, I rejected 18% of first deliveries due to cutting inconsistencies. This checklist came out of that pain.

Here are the 7 steps I now run on every xTool S1 acrylic job before we even press start.

Step 1: Verify Your Material (It's Not All 'Acrylic')

This sounds basic, but it's the most common error. Not all acrylic is the same for diode lasers like the xTool S1. You need specifically cast acrylic. Extruded acrylic often leaves a frosted, uneven edge or, worse, won't cut at all because it melts inconsistently.

The Quick Check: Look for the protective film. Cast acrylic typically has a white or clear film. Also, if the material feels slightly 'greasy' on the surface, it might be extruded.

If you're unsure, do a small test cut in a corner. The edge should be smooth and clear. If it's milky or has ridges, you're likely using the wrong material. (I learned this the hard way on a 50-unit order—ugh. Ended up re-cutting the entire batch.)

Step 2: Confirm the 'Cut' vs. 'Engrave' Power Baseline

Standard 'xtool s1 acrylic cutting settings' online are a starting point, not a final answer. For the xTool S1 20W laser engraver, a common baseline for 3mm clear cast acrylic is: Speed: 5 mm/s, Power: 100%. For 5mm, you'll likely need two passes.

But here's the catch. Power isn't just a number; it's a function of your machine's current state. Before every job, I run a single-line test pass on a scrap piece. I want to see if the beam is actually delivering the full 20W. Put another way: I'm checking for 'power drift.'

If the test line is noticeably thinner or lighter than the last session, your laser module lens might need cleaning or the tube is aging. Don't trust last month's settings file. Verify them now (surprise, surprise—this saves a lot of waste).

Step 3: Inspect the Honeycomb Panel (This is the 'Ignored' Step)

Most people focus on the laser head. I focus on the honeycomb panel. A dirty honeycomb is the #1 cause of incomplete cuts on the xTool S1 in my audits. Debris and tape residue can reflect or block the beam on the backside of the acrylic.

The Check: Lift the panel and look directly through the honeycomb matrix. If you see any bright spots, glue, or charred debris, clean it. A quick pass with a scraper or a fine-grit sanding block (220 grit) fixes it in under a minute.

This one-minute check has prevented failed cuts on at least 150 pieces this year. Aesthetics matter, but this is basic physics: if the beam can't escape cleanly, your cut won't be clean.

Step 4: Calculate Your 'Bottom Film' Strategy

Cast acrylic usually has a paper or plastic film on both sides. You should leave the bottom film on during cutting. It acts as a 'draft shield' and reduces the flame-prone residue on the cut edge. (The top film—I remove it for the best focus).

But here's a nuance: if the bottom film is polyethylene (the shiny, stretchy kind), it can melt into the cut edge and create a rough finish. Test a sample. If it does, you need to flip the acrylic so the paper-based side is down, or use a different masking material.

This is one of those details where spending two minutes testing saves you twenty minutes of deburring. The cost increase is $0 for the test, but the time saved is measurable.

Step 5: The 'Air Assist' Nozzle Alignment

Your xTool S1 comes with an air assist. This is critical for acrylic to blow away flammable gases and cool the cut edge. But the nozzle must be precisely aligned with the laser beam. If it's even 2mm off, it's just blowing air into a wall.

My check: Place a piece of tape over the laser head opening. Fire a single low-power pulse (1% power at 100mm/s). This burns a small hole. The air assist nozzle should be centered directly over that hole. If it's not, loosen the nozzle and adjust.

I keep a 'focus gauge' jig to ensure the nozzle is always 10mm from the material surface. Too high, and the air jet is ineffective. Too low, and it can disturb the material. This is pure geometry—standard physics, really.

Step 6: Run a 'Multi-Pass' Stress Test

For acrylic thicker than 3mm, you might think 'one slow pass' is cleaner than 'two faster passes.' In my experience, this is wrong. One slow pass on 5mm acrylic generates too much heat, leading to melted edges and burning.

The xTool S1 20W laser engraver handles 5mm better with two passes at 7 mm/s and 80% power, with a 5-second wait between passes for the material to cool. The cool-down prevents heat buildup. This is especially important for colored acrylic, where heat changes the final pigment.

I still kick myself for the times I didn't do this and ended up with a batch of 'glowing' edges that turned brown. The scrap was significant, and the cost was mine—not the client's.

Step 7: The Final 'Edge Glazing' Check

After the cut, wipe the edge with a soft cloth and isopropyl alcohol. If the edge is not perfectly transparent or has a 'flame-polished' look that's slightly wavy, your speed is too low for the power. Speed up by 1-2 mm/s on the next test piece.

The goal is a flame-polished edge that is perfectly flat and optically clear. It should match the quality of a CO₂ laser cut. If it doesn't, go back and re-check steps 2 through 5. (As of January 2025, this standard hasn't changed. Our audits still use the same visual criteria.)

Final Notes & Common Mistakes

• Power consumption isn't the same as power at the lens: The electrical input power (e.g., 50W for the 20W module) doesn't equal output. Don't rely on the wattage displayed in software. Verify with a test cut.
• Rotary accessories change the z-height: When using the rotary bundle, your focus shifts. Don't assume your 'flat' settings work. Re-calibrate.
• Don't skip the fire watch: Acrylic is flammable. The cut generates hot particles. Stay with the machine, and keep a fire extinguisher nearby. This isn't a suggestion; it's safety 101.

This 7-point checklist has saved us an estimated $4,000 in rework this year. It's not exhaustive—it's practical.