Cutting MDF on the Ray5 20W — Speeds, Venting, and Tips
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MDF cuts cleanly and cheaply on the Ray5, but it produces the most toxic dust and fumes of any common laser material. Ventilation is mandatory.
Why MDF Is Risky
MDF contains formaldehyde-based urea-formaldehyde resin. When laser cut, it releases formaldehyde gas and fine particulate. Not a "crack a window" situation — proper exhaust is required.
Ventilation Setup
- Exhaust fan connected to laser enclosure pointing outside
- Or: dedicated laser air filter (with activated carbon for VOCs)
- Minimum: box fan + furnace filter positioned to pull air away
- Never cut MDF in an unventilated space
Cutting Settings
| Thickness | Speed | Power | Passes |
|---|---|---|---|
| 3mm | 350 mm/min | 100% | 3 |
| 6mm | 200 mm/min | 100% | 5–6 |
| 9mm | 150 mm/min | 100% | 7–8 |
Air assist is essential — clears debris, reduces flaming.
Getting Clean Edges
- MDF cuts with a dark brown char on edges — this is normal
- Multiple slower passes = less char than one fast pass
- Mask top surface with masking tape to prevent smoke staining
- Wipe edges with dry cloth immediately after cutting
Focus
MDF is uniform density — focus at the surface. Standard spacer position.
Engraving MDF
MDF engraves uniformly — no grain to fight.
| Speed | Power | Result |
|---|---|---|
| 3000 mm/min | 30% | Light surface mark |
| 2000 mm/min | 45% | Standard dark engrave |
| 1000 mm/min | 60% | Deep cut-style engrave |
Priming for Paint
Laser-cut MDF edges are porous. Before painting:
- Apply diluted wood glue to all cut edges
- Let dry
- Sand lightly (320 grit)
- Prime and paint