OMTech 80W CO2 Laser
OMTech 80W CO2 Laser
⚠️ NEVER LEAVE THE LASER UNATTENDED WHILE RUNNING ⚠️
The OMTech 80W CO2 laser is GRM's primary workhorse machine for cutting and engraving a wide range of non-metal materials. This page covers software, setup, settings, safety, and tips to help you get great results.
Software
LightBurn (Recommended)
LightBurn is the primary software for controlling the laser and designing files. It runs on the dedicated computer and large monitor next to the machine.
GRM Members: 75% off LightBurn Pro (~$50 instead of $199). Ask a staff member or volunteer for the discount code, or email chris@grandrivermakerspace.org.
See the Software & Design section of the main laser page for full details and tutorial videos.
Other Design Software
You can design in any of the following and import into LightBurn:
| Software | Cost | Export Formats | Notes |
|---|---|---|---|
| Inkscape | Free | SVG | Native SVG works great with LightBurn |
| Affinity Designer | Free | SVG, PDF, EPS | Professional-grade vector tool |
| Adobe Illustrator | Paid | SVG, EPS, DXF, DWG, AI | Industry standard |
| Any 2D/3D CAD program | Varies | DXF, DWG | Export as DXF or DWG for best results |
File Formats
The CO2 laser works with 2D flat files only — no 3D formats.
Vector Files (preferred for cutting and engraving)
- SVG, DXF, DWG, EPS, AI
- Can be scaled to any size without losing quality
- Allows you to assign different laser operations to different areas of your design
Raster Files (for photo engraving)
- JPEG, PNG, and other pixel-based images
- Used with LightBurn's dithering/raster engraving mode
- Works well for high-resolution photos (pets, portraits, etc.)
- Produces a dot-pattern effect — closer dots = darker tones
To convert a raster image to vector: use the trace function in Inkscape, Adobe Illustrator, or Affinity Designer.
Startup Procedure
Complete all four steps in order before operating the machine:
- Power on the laser
- Turn on the air compressor
- Turn on the water chiller
- Turn on the exhaust fan — set to 10; listen to confirm it's running
⚠️ If the exhaust fan isn't running, the workspace will fill with smoke. Always confirm it's on before starting a job.
Focusing the Laser
You must manually focus the laser nozzle to your material before every job.
- Press the C/U button on the laser control pad to enter bed movement mode
- Use the left/right arrow buttons to raise or lower the bed
- Use the focus distance stick (stored near the machine, attaches by magnet) to set the correct gap between the nozzle and the material surface
⚠️ Autofocus is currently not working. Do not use the autofocus button — always focus manually.
| Lens | Focal Length | Notes |
|---|---|---|
| Standard lens | 2 inches | Default; installed on the machine |
| Optional lens (orange) | 1.5 inches | Stored separately; ask staff for assistance; best for fine detail work |
LightBurn Settings
Layer Types
Every object in your design gets assigned to a colored layer. The two most useful modes are:
- Fill — for engraving (fills in a solid shape)
- Line — for cutting or outline engraving
You'll typically only need 1–2 layers per project (e.g., one engrave layer + one cut layer).
⚠️ Layer order matters: Run engraving operations first, cutting operations second. This prevents cut pieces from shifting before engraving is complete.
Power & Speed
These two settings work together:
- Lower speed at the same power → darker/deeper result
- Higher speed at the same power → lighter result
- Higher power → darker/deeper mark, risk of burning through
Starting point settings for Baltic birch plywood (1/8"):
| Operation | Speed | Power |
|---|---|---|
| Light engrave | 50 | 35–40% |
| Deep engrave | 50 | 55–65% |
| Cut (1/8") | 15 | 75% |
| Cut (1/4") | Slow, multiple passes | 75% |
⚠️ Avoid running long jobs above 75–80% power — it shortens the life of the laser tube.
⚠️ Do not exceed ~300–350 mm/s for engraving — the machine will shake and produce poor results.
Line Interval (Lines per Inch)
Think of this like layer height in 3D printing:
| Interval | Result | Best For |
|---|---|---|
| 0.2–0.45mm | Faster, less detail | Large text, signs |
| 0.1mm | Balanced | Good all-around starting point |
| 0.05–0.06mm | Slower, more detail | Fine detail work |
Min/Max Power
When double-clicking a layer to access advanced settings:
- Max power — your main power setting
- Min power — set 3–5% below max; helps reduce charring on corners and curves
Kerf Offset
If you're cutting joinery (e.g., finger joints, press-fit boxes), calibrate a kerf offset in the layer settings to account for material removed by the laser beam.
Coordinate Systems & Origin
LightBurn offers three coordinate modes — choose one before framing or running your job:
| Mode | How It Works | Best For |
|---|---|---|
| Absolute Coordinates | Uses machine home (back-right corner) as 0,0 | Repeatability with fixed jigs |
| User Origin | You set origin on the machine controller; select matching dot in LightBurn's 3×3 grid | Aligning to a specific corner or edge |
| Current Position | Job starts wherever the nozzle currently sits | Quick one-off jobs |
Centering tip: Find the center of your material, mark it lightly, move the nozzle there, and select the center dot in LightBurn's 3×3 origin grid.
Framing & Preview — Always Do This First
Before running any job:
- Frame (square icon) — Traces a bounding box around your design. Confirms the job will land where you expect.
- Contour Frame / Rubber Band (circle icon) — Traces the outer edges of your actual design shape. Useful for maximizing scrap material.
- Preview (monitor icon) — Shows an estimated run time and a simulation of what will be engraved/cut.
Material Test Cards
When working with an unfamiliar material, always run a test card first rather than committing to your full workpiece.
In LightBurn, generate a material test grid that varies power, speed, and line interval. Run it on a scrap piece of the same material, then identify the settings that produced the look you want.
Quick alternative: Cut small shapes (1/4" or 1/2" circles/squares) on scrap to verify cut-through before running a full job.
Materials Reference
✅ Approved Materials
| Material | Cut | Engrave | Notes |
|---|---|---|---|
| Thin plywood (up to 1/4") | Yes | Yes | Slow speed or multiple passes for thicker stock |
| Baltic birch plywood | Yes | Yes | Best all-around material for CO2 |
| Acrylic (cast, 1/8") | Yes | Yes | ~5 speed, 75% power; slower than wood |
| Glass | No | Yes | Engrave only; cannot cut through |
| Granite / Stone | No | Yes | Engrave only |
| Leather (veg-tanned only) | Yes | Yes | Chemical-free only — see warnings below |
| Cardboard / Paper | Yes | Yes | Low power; monitor closely for fire |
| Natural fabrics | Yes | Yes | Low power; watch for ignition |
❌ Never Cut These Materials
| Material | Why |
|---|---|
| PVC / Vinyl | Releases chlorine gas — dangerous to people and damages the machine |
| Chrome-tanned Leather | Contains toxic chemicals that release harmful fumes |
| Polycarbonate (Lexan) | Produces toxic fumes; catches fire easily |
| ABS Plastic | Releases cyanide gas |
| Fiberglass / FR4 | Releases carcinogens |
| Foam with unknown coatings | Risk of toxic fumes |
⚠️ If you don't know what a material is made of, don't cut it. When in doubt, ask a staff member or volunteer.
Safety Rules
- Always stay by the machine while it's running. Never leave a running job unattended.
- If you need to step away: hit Pause on the machine — it will stop mid-job and you can resume when you return.
- Ask another member or the on-duty volunteer to watch your job if you must step away briefly.
- CO2 fire extinguisher is located to the left of the machine against the wall.
- Fire blanket is also located near the machine on the East Wall.
- Air assist should be on for most jobs — it clears smoke from the cut zone and improves cut quality.
Helpful Features
Batch Processing Tips
When running large batches (e.g., 100 name tags from a sheet):
- Work in rows — if something fails, you don't lose the whole sheet
- Use Tool Layers (T1/T2) — objects on tool layers are used for selection/framing reference but the laser won't fire on them; useful for alignment geometry
Power Resume
If there's a power outage mid-job, the machine has a job resume function — you don't necessarily have to start over.
Saving Your Settings
Keep a record of your successful settings — don't rely on memory:
- Save your LightBurn project files with descriptive names (e.g., slate-coaster-2025)
- Store files in Google Drive or on a flash drive
- The built-in material library in LightBurn is community-edited and may not be accurate — use it as a starting point, not gospel
Rotary Engraving
Rotary engraving (for tumblers, cups, etc.) on the CO2 laser is an advanced setup using the PiBurn Laser Rotary 4.0. GRM offers a dedicated tumbler engraving workshop — see our events page for upcoming dates.
Tip: For powder-coated tumblers specifically, the UV laser is currently an easier option — less setup, less invasive process.
Design Resources
| Resource | Description | Link |
|---|---|---|
| Cuttle | Parametric laser design templates; outputs SVG for direct import into LightBurn. Free tier available. | cuttle.xyz |
| Etsy | Many free/paid laser-ready SVG and DXF files | etsy.com |
| Maker World | Free laser-ready files from the maker community | makerworld.com |
| Thingiverse | Free community files including laser designs | thingiverse.com |
| GRM Discord / Volunteers | Ask for help with settings, file prep, or troubleshooting | Ask at the space or in Discord |
Troubleshooting & Staff Notes
- Autofocus: Currently disabled — do not use the autofocus button. Always focus manually.
- Lens condition: Lenses get dirty and need periodic cleaning or replacement. If cuts are inconsistent or quality has dropped, the lens may need attention — flag for a knowledgeable volunteer.
- Questions or issues: Leave a note on the whiteboard by the machine, or flag the on-duty volunteer.
