Contrary to both intuition and what some of the replies say, I HAVE done several burned in patterns on the back of a bow, and SOME survived. This was before I knew better, BTW.
It worked better on bamboo than one wood. The deal was I used a VERY hot flame, like a propane torch, that will darken the very most shallow layer of wood super quickly, like literally less than a second in any one spot. Like, swing it across an inch away and only make one pass. I did chevrons down the limbs of on bamboo back that were pretty cool..
BUT, I wouldn't do it today. I have enough problems with the edges of a back getting too much heat bouncing off the form when belly treating, as it is.
Woodburning can look darn cool in handles and shelves. I love that heat treating bellies usually leaves a dark and light random pattern no matter how evenly I try to cook it.
If you do it to limbs or handle, clamp it down first, too, because sometimes a stave will react wildly to even a little heat.
