Roughly speaking (I am no expert) a burring machine forms a small 90-degree lip on the edge of a piece of tin. This tool is especially useful when forming a lip on a circle such as on the bottom of a cup. (See picture of tin bottom)
This machine was horribly rusted and I suspect it spent a lot of time in water. After soaking in rust remover I wired brushed the metal and painted the areas black that were once coated in black japanning. The original wooden handle was shot so I turned a new one on the lathe shined up the brass and put it back together. The forming heads are pitted from rust so they tend to transfer the roughness to the tin but other than that it seems to work. Pretty good for a tool around a 150 years old.
From all I’ve read and watched on videos, this is not an easy tool to use. I will need a lot of practice. But overall I am happy with the finished results.