The rasps on hand at Boonesborough were a US Nicholson 49 and 50, a MicroPlane flat course rasp and a rounded profile Iwasaki.
The Nicholsons look much like the antique rasps in Mr. Everett's post. The Microplane and the Iwaski are both very different designs than conventional rasps.
Microplane - those aren't teeth in the rasp sense, each one is a tiny blade.
Iwasaki - rather than conventional rasp teeth, these are rows of tiny scrapers.
The Nicholson 49 and 50 rasps both have a flat side and a rounded side on one tool. More bang for the buck. But the US made versions can be nearly impossible to find.
The Microplane and the Iwasaki have only one cutting surface per tool, so if you want a flat and a curved you have to buy 2 tools. The Iwasaki is priced in the $35 to $40 range. Peachtree Woodworking Supply sells the Microplane handle with 1 blade for $10.99, and other blades that fit the same handle are $7 and $8 each. if you are on a tight budget, these are the way to go.
Rasps produce sawdust, the Microplane and the Iwasaki produce shavings. I think everyone agreed that all the tools we had on hand were good serviceable tools, but the favorite was the Iwasaki. It moved the most wood, but left a fairly smooth surface.
I hope other attendees at Boonesborough will chime in with their take on these tools.
-Ron
