How to Get Black Wood Engravings?
Posted by Gray Chen on
Background
Wood engraving with a diode laser is a fantastic way to create personalized art, signs, or custom gifts. But if you're aiming for those striking black engravings—deep, dark burns that really pop against the wood grain, using borax can be of great help since it can can create deep, dark burns that stand out. This blog explains the process.
What is Borax?
Borax, or sodium tetraborate decahydrate (Na₂B₄O₇·10H₂O), is a naturally occurring mineral compound often used in cleaning, laundry, or as a flux in metallurgy.
Why choose Borax for laser Engraving?
In laser engraving, borax acts as a heat-resistant aid: it cools the wood slightly during engraving, reduces fumes, and forms a protective layer that promotes cleaner, darker burns. This leads to enhanced contrast and those coveted black engravings. Borax is typically mined from evaporated lake beds, with major deposits in places like California’s Death Valley, and it’s widely available as a powder in stores so it's pretty easy to buy.
For diode lasers like NEJE models, which use blue light, borax is particularly effective because it helps manage the intense heat that can otherwise cause excessive smoke or uneven charring. It’s affordable (often under $5 for a box), non-toxic in small amounts when handled properly, and easy to apply, making it a favorite among laser enthusiasts.
Step-by-Step Guide
1. Prepare Your Wood Surface
Start with a clean, flat piece of wood. Sand it lightly to remove any imperfections or coatings, as these can interfere with the laser or borax absorption. Wipe away dust with a dry cloth. If your wood is uneven, it might cause inconsistent engraving depths.
2. Make and Apply the Borax Treatment
Mix borax with hot water (about 1:1 ratio). Apply the paste evenly to the area you'll engrave. Use a brush or sponge for a thin, uniform layer. Let it dry completely (10-15 minutes). The borax forms a subtle crystalline coating that regulates heat during engraving.
3.Set Up Your NEJE Laser
Mount your wood securely in the NEJE machine. Focus the laser precisely and prepare your engrvaing picture or file. Borax allows for slow power settings with less smoke, so basically you can push the limits safely.
4. Engraving!
Run the job in a ventilated area. The borax will reduce smoke and help the laser create crisp, black lines or fills. Monitor the process; if it smells too burny, pause and adjust speed or power.
5.Post-Engraving Cleanup
Once done, brush off any loose borax residue with a soft brush or cloth. Gently sand if needed for smoothness, but avoid over-sanding to preserve the black depth. Seal with a clear coat (like polyurethane) to protect the engraving and enhance contrast.