Step 3: Sharpening the gouge
1. Roughing Gouge - This is a large gouge with high sides used for rouging stock into a round shape. This gouge is typically ground straight across.
2. Continental Gouge - This is the gouge usually included in cheap tool sets, it is similar to a roughing gouge but has much lower sides. Expect to find this gouge shoved in a corner with a straight grind, this is a shame because I find the continental gouge with a mild fingernail grind to be an incredible forgiving chisel capable of producing a finish almost as good as a skew.
3. Spindle gouge - This is usually ground from a solid bar of steel with a wide shallow grind. These work great with all kinds of grinds for different situations.
4. Bowl gouge - These beasts are ground from a solid bar steel and can be found with all kinds of grinds on them, I have models with straight grinds, fingernail grinds, and aggressive swept back designs. Different areas and bowl types call for different grinds, I find a swept back design great for hogging out a bowl but too aggressive for finishing cuts and usually switch to a milder grind.
Those are the gouges so let's talk about the grinds.
For most all gouges around 60 to 70 degrees is a good starting angle to grind, as you get more comfortable or just want a more aggressive chisel you can go below 60 degrees but be careful these things can take a lot of wood off fast and you need a lathe with some good horsepower to hog off that find of wood.
The most basic and simple way to grind a gouge is to set the angle on the flat tool rest right and then roll the tool back and forth until sharpened, this creates a tool with a straight cutting edge and high wings.
Every other grind takes either experience of a good jig, there are many brands of jigs to choose from or you can do like me and make your own jig. Just do a quick google search for "homemade fingernail grinding jig" without the quotes for plenty of ideas. As you can see in the pictures of my jig I have marks for the angle of the arm, basically the further forward the arm is the more swept back the grind. So for a basic continental gouge I will have the arm all the way back for a basic almost straight fingernail grind, for a swept back bowl gouge I will have the arm all the way forward and in between those two extremes is everything else.
As you can see I have a block of wood mounted on the grinder platform, this is my gauge on how far the tool extends from the jig, I use 2" for everything, it just keeps things simple.
So once you have your tool in the jig and the arm of the jig adjusted to where you want it, adjust the v-arm of the grinder rest in our out to get the right front angle on the grinding wheel. Then you simply start grinding swinging that tool handle side to side in a nice slow and smooth manner. As you can see going back to the grinder every time you need to touch a tool up can be a pain which is going to lead into the next step.