Fuzzy Mahogany

Tension wood may exhibit more "fuzz" than wood that was not stressed during tree growth. December 24, 2012

Does anyone have tips for dealing with the fuzz that is sometimes present in the grain of some mahogany? I know it's best to try not to use it, but there you are. Just sand until gone, or fill with epoxy and then sandů?

Forum Responses
(Architectural Woodworking Forum)
From contributor P:
I've been stuck working with thousands of BF of the fuzz. Seems to be more common these days due to dwindling supplies of good lumber. Shellac seems to be the best for eliminating the fuzz and allowing me to sand, finish, stain, etc. Be sure to test on scrap first and cut the shellac if needed. I have also used West System epoxy. I would be curious as to what causes the fuzz. Improper drying or reaction wood seems to be my conclusion.

From contributor L:
Reaction wood is my best guess. From my experience, you can never make it into good stuff.

From Professor Gene Wengert, forum technical advisor:
The fuzz could be caused by wetter wood, but it is much more likely that it is a special type of wood cell that forms in the growing tree called tension wood. Tension wood is typically much higher than normal in cellulose content and much lower in the stiffener chemical called lignin. So, tension wood fibers are weaker than normal and will fold over rather than cut cleanly. Oftentimes with a finish, they will pop up through the finish.

The cure is to first use sharp tools (no carbide) and sharp (= fresh) sandpaper. The sharpness will cut these weak fibers. A second approach is to use something to stiffen them, such as a sanding sealer or glue sizing. As this only stiffens the fiber, which makes it easy to cut, one must be careful not to sand very much, as you can sand through this coating and get down to fresh wood.

I do have an article in my old book "The Wood Doctor's Rx" that I can send if you need more, but I think this above covers it. We do see this fuzz in yellow poplar, red oak, and many other species.

From the original questioner:
Thank you, Gene; as usual your wisdom is most welcome. I ran the gates through the widebelt slowly with #80 and this took care of the problem.