How to Burnish Leather
Burnishing is the process of buffing leather edges to a slick, glossy finish. Burnishing is aesthetic – it looks nice to have the shiny edge. But it also serves a functional purpose. When you burnish leather, you seal the cut edge by applying friction. The heat from the burnishing tool compresses the fibers of the leather together. By sealing the edge in this way, the leather retains its natural oils and moisture and won’t dry out. It also creates a waterproof barrier so the leather won’t absorb moisture. This helps prevent your thread from rotting.
Burnishing works best on vegetable tanned leather, as even thin, lightweight veg tan is stiff enough to hold up to the friction of a burnishing tool. You can burnish before or after dyeing a leather edge, though we recommend burnishing after to maintain a high gloss finish.
With a Hand Burnisher
The most common leather burnishers, also called leather slickers, are made of wood. These tools fit into the palm of your hand and usually have a grooved end to accommodate a range of leather weights. Hand burnishers can also be made of plastic or glass. Before using a hand burnisher, sand the leather’s edge, especially if you’ve glued pieces together. Sanding ensures a smooth, flat edge and that the leather pieces are completely flush. It also removes any excess glue that may have seeped over the edge. Once your edges are smooth, bevel the edges to give a rounded appearance and make it easier to burnish.
Working in short sections, coat the edge with a lubricant, such as water, beeswax, gum tragacanth* or saddle soap. Wax, gum and saddle soap heat up during the burnishing process and settle into the leather fibers, resulting in a smoother and shinier finish. Quickly run your burnishing tool along the edge, applying enough pressure to create friction.
You may have to apply lubricant and burnish several times in order to achieve your desired look. If you find you aren’t getting results, your edges may be too dry.
Once you’re happy with your burnish, you can buff the edges with canvas cloth for additional shine. If desired, add a little oil or wax to the cloth to condition and protect the edge.
With a Burnishing Machine
As with hand burnishers, there are several options for machine-powered burnishing tools. A bench- or table-mounted burnisher bolts to your work surface so it is always accessible. These are often multiuse tools with multiple attachments for different aspects of burnishing, including a sanding drum to smooth and flatten edges, plus a grooved wood burnishing tip for a range of leather weights. It is also possible to purchase burnishing attachments for a standard rotary tool or drill.
Using a burnishing machine follows the same steps as hand burnishing: sand, bevel, lubricate and then burnish. When using a power-operated burnishing tool, it is important to keep an eye on the speed of the device or you can burn the leather.
We hope this blog helped you learn a bit more about leather burnishing and the tools you can use to achieve a shiny, polished edge on your leather goods. Be sure to check out our other blogs on leather techniques. Learn about the tools and techniques used to mark leather, adhere leather pieces together, how to measure leather, and how to finish leather edges. Sailrite is your destination for leather tools and the knowledge you need to become a master leather crafter.
*Gum tragacanth is a natural, viscous mixture made from plant sap and is popularly used as a burnishing compound.