Spyke

ceramic rods

touching up regularly to keep gauges sharp is much easier than dulling the edges and needing to resharpen

6

veeeeery carefully

jokes aside, an outside radius you can do without a problem on a flat stone, on an inside radius either get yourself a round stone, or wrap sandpaper around a dowel

3

Find someone with a Tormek sharpening system with the woodturners kit, and beg to use their Swedish shapening marvel.

2

Variable speed and fine grit. I have used the one I linked a ton to sharpen all sorts of tools. Also it's literally listed as a tool sharpener.

1

Convenient way is sandpaper and a dowel of a similar diameter of the gouge. The best way is to get gouge sharpening stones because I hate sharpening on sandpaper.

1

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