When This Checklist Applies (And When It Doesn't)
If you're looking at your xTool S1—with its 20W or 40W diode laser module—and wondering if you can add metal engraving to your service offerings, this checklist is for you. I'm a quality and brand compliance manager for a small manufacturing workshop. I review every piece of equipment and process we bring in, and I've rejected proposals that promised more than they could deliver. This isn't about industrial-grade metal cutting; it's about understanding what a desktop diode/CO2 laser system can realistically do to metal surfaces for marking or light engraving.
This checklist won't help you if you need to cut through sheet metal. For that, you're looking at fiber lasers or industrial CO2 systems. But if you want to personalize tools, create serial numbers on metal parts, or add logos to anodized aluminum, follow these steps. There are 5 key checks to run before you fire up the laser.
The 5-Point Pre-Engraving Checklist
Step 1: Verify Your Metal Type & Surface Coating
This is the make-or-break step. The xTool S1 doesn't engrave bare, untreated steel or aluminum directly. It works by altering a surface coating. You need to know exactly what you're working with.
- Anodized Aluminum: This is the ideal candidate. The laser removes the colored anodized layer to reveal the silver metal underneath, creating a high-contrast mark. It's clean and permanent.
- Painted or Powder-Coated Metal: The laser can vaporize the paint/coating to expose the bare metal beneath. The result depends entirely on the coating's thickness and composition. Test first.
- Stainless Steel with a Marking Spray: This is a common workaround. You apply a special compound (like Cermark or Dry Moly Lube) to the bare metal. The laser bonds this compound to the surface, creating a permanent, often dark, mark.
- Bare, Untreated Steel/Aluminum/Copper/Brass: You'll get, at best, a very faint discoloration. It's not a reliable or professional engraving method for these materials with a diode or CO2 laser at this power level. Don't let anyone tell you otherwise—I've seen vendors promise this, and the results were unusable.
Checkpoint: Can you definitively identify the metal's coating? If it's bare and shiny, you'll need a marking spray.
Step 2: Confirm Your Laser Module & Power Settings
Not all xTool S1 setups are equal. Your module dictates your approach.
- 40W Diode Laser Module: This is your best bet for metal marking. The higher peak power allows for better interaction with coatings and marking compounds. You'll likely use lower power (15-30%) at high speed for multiple passes to avoid overheating the coating.
- 20W Diode Laser Module: It can work, especially on anodized aluminum, but will require more passes and finer tuning. Patience is key. Don't crank the power to 100% expecting a miracle—you'll just burn the coating.
- CO2 Laser Tube (if equipped): CO2 lasers (like a 40W tube) are generally better for engraving coated metals and using marking sprays than diode lasers at equivalent wattage. The wavelength interacts more efficiently. If you have this option, use it for metal.
Checkpoint: Know your module type and have the manufacturer's recommended starting parameters for metal marking handy. Don't guess.
Step 3: Run a Material Test Grid (The Non-Negotiable Step)
Never, ever run a final job without a test. I've rejected batches where the vendor skipped this. The cost of a ruined product is higher than the time for a test.
- Take a scrap piece of the exact same material from the same batch.
- In your laser software, create a small grid of squares or text.
- Run the test using a range of power/speed combinations. For example, try speeds from 100 mm/s to 300 mm/s and power from 15% to 40% (for diode).
- Mark each test square with its settings so you don't lose track.
The goal is to find the setting that gives you a clean, contrasty mark without damaging the substrate. On anodized aluminum, you want clean removal without a deep, rough etch. With marking spray, you want a solid, dark bond.
Checkpoint: Do you have a physical test sample with clear, labeled results that you're happy with?
Step 4: Secure the Workpiece & Calibrate Focus
This seems basic, but it's where small errors happen. Metal is reflective, which can pose a slight risk to the laser module itself (though xTool S1 has protective measures). More importantly, if the metal sheet is even slightly bowed, your focus will be off, leading to blurry or inconsistent marks.
- Use the honeycomb bed or clamping system to ensure the metal is perfectly flat.
- For cylindrical items (using the rotary tool), ensure it's seated securely and the axis is aligned. A wobble will ruin the engraving.
- Use the manual focus tool or auto-focus (if your model has it) to set the focal point precisely on the material's surface. Re-check this if you change material thickness.
Checkpoint: Is the material rock-solid with no movement, and is the laser focus precisely calibrated to the surface?
Step 5: Manage Expectations on Speed & Depth
This is the transparency step. Desktop laser marking on metal is not fast, and it's not deep. If you're coming from engraving wood or acrylic, you'll need to adjust your workflow and pricing.
- Speed: You'll often use high speed with multiple passes to avoid heat buildup. A detailed graphic might take 5-10 minutes, not 30 seconds.
- Depth: You are marking or removing a coating, not engraving deep into the metal. The result is largely two-dimensional.
- Contrast: The final look depends on the base material and coating. On anodized aluminum, you get a clean, silver mark. With marking spray on steel, you get a dark, often black, mark.
Be upfront with customers about this. It's better to show a realistic sample and explain the process than to overpromise. I learned this the hard way early on—we quoted based on acrylic speed, lost money on the job, and the client wasn't thrilled with the timeline. Now, metal jobs have their own quote template.
Checkpoint: Have you timed a sample run and set realistic customer expectations for both timeline and final appearance?
Common Pitfalls & Final Reality Check
Before you hit start on a paid job, run through these final warnings:
- Ventilation is Crucial: Engraving paints, coatings, or marking sprays produces fumes that are not the same as wood smoke. Ensure your ventilation is robust and you understand the safety data sheets for any marking compounds.
- Reflective Backing: When engraving thin sheet metal, place a non-reflective material (like cardboard or masking tape) underneath to prevent the laser beam from reflecting back up after passing through.
- The "Can It Cut?" Question: Let's be definitive: No, the xTool S1 cannot cut through sheet metal. It lacks the power density. Any claim otherwise is setting you up for damaged materials, a damaged lens, and frustration. It's a marker, not a cutter, for metal.
- Start as a Side Service: If you're thinking of starting a laser engraving business from home, metal marking can be a valuable add-on service. But don't build your initial business plan around it. Master wood, acrylic, leather, and glass first. Those materials are more forgiving and will let you dial in your process before tackling the tighter tolerances of metal.
Bottom Line from the Quality Desk: The xTool S1 is a remarkably versatile desktop machine. With the right material prep and managed expectations, you can produce professional, permanent marks on coated metals. But its capability has a clear boundary at the edge of true metal cutting or deep engraving. Success comes from respecting those boundaries, testing relentlessly, and being transparent with yourself and your customers about what the tool can actually deliver.
Note: Laser capabilities and material interactions can vary. Always consult your xTool S1 manual and safety guidelines, and conduct your own material tests before production work.
