Thanks Robin. My left hand was alright. I used the rougher surface to carve the neck so my hand was on the finer side.
You could always get some gloves which could help.
I love the Shinto rasp! I bought one after you mentioned it on the superstrat build and they are awesome, but yeah, you could take a finger off if you aren't careful. I tend to wear a rigger's glove on my front hand to guide it as I work.
FrankenLab Hand crafting guitars, because Death Rays are expensive.