PDA

View Full Version : Burnishing



Rich Stewart
01-11-2006, 9:23 PM
Can somebody tell me exactly what 'burnishing' means?

Michael Stafford
01-11-2006, 9:38 PM
Rich, I assume you are referring to the technique of taking a handful of shavings and rubbing them against your spinning turning to get a nice polished finish. In the old days before the advent of modern sandpaper that was the preferred method to polish up/smooth a turning. Now with fine grit papers we can sand wood much smoother than burnishing will acheive. I may be incorrect about this but that is my understanding.

Jack Wood
01-11-2006, 9:44 PM
It also applies to the process of sharpening a scraper edge. The tool used for it is a hardened rod called a burnisher, that curls back the rough edge to a particular angle so that it forms a cresting wave look or there abouts. But Michael is also right about it in turning wood. :)

Carole Valentine
01-11-2006, 10:03 PM
Burnishing is good as a final step in sanding (with wood shavings or a piece of brown paper bag) but it is not good when it is done as a result of using worn out sandpaper at a high speed that produces a lot of heat and little cutting action. It compresses the fibers instead of cutting them. Probably also has an effect on any resins present in the wood.

Richard Allen
01-12-2006, 8:07 PM
Burnishing is the act of bending over. In woodturning this is primarly the bending of wood fibers. You can bend over the wood fibers in many different ways. When you "rub the bevel" you are cutting the wood fibers and then burnishing the wood fibers. You can burnish the wood with a handfull of shaveings. This is usualy done after all sand grits have been used. The beauty of burnishing with shavings is that you are doing this with all the sharp edges of the shavings. But because the shaveings are of the same wood that is being burnished you are very unlikely to scratch the wood.

Burnishing yeilds a very smooth surface. That smooth surface can inhibit the absorption of finish. So while that smooth surface before finish might look GREAT the durablity of the finish could be lacking.

Please note that you can also burnish wood with sandpaper. Open grain woods with burnish at a coarser grit than fine grain wood. For example, sanding poplar with 1200 grit sandpaper will burnish the wood. Where sanding dogwood with 1200 grit can remoce wood yeilding an even smoother surface.

Rich Stewart
01-12-2006, 9:31 PM
Thank you for taking the time to answer. I got it now.