Na'tl Geog ran an article many years ago, comparing a modern scalpel and an obsidian edge. There was no comparison, the obsidian won hands down.
In the era of wooden ladders, we used to 'shave' them each year, using pieces of glass instead of scrapers. This, under the tutelage of an Ahab-like old Chieftain who would almost foam at the mouth at the daily suggestion of using conventional paint scrapers,
'NOT GOOD ENOUGH!! NOT GOOD ENOUGH!!'
I'll have to admit, although it took literally *weeks* to strip a 50' ladder, by the time it was considered 'good enough', it was smoother than a baby's bottom.
The old guy also carried a set of sailmaker's needles with him. These were god knows how old, and looked like curved suture needles, except that they were about 2 inches long and an eighth of an inch thick. If you weren't shaving wood, you were patching the oiled canvas tarps used for Salvage, or the canvas turnout coats we wore at the time.
This was part of our 'Wheel of the Year' we operated under, that was brought forward, essentially intact, from Colonial times. Lost now.
::::whips out an oversized hanky:::
<< SNIFF>>
:::: HONK :::::