Reddit reviews Grizzly Industrial G9717 - 6" Bench Grinder w/ 1/2" Arbor

Well, of course the main thing (and really the only thing you need until you start getting fancy) is a (dry) bench grinder. Here's one that gets mentioned a lot, and here's the one I have.

8" is better than 6", and low speed (1750 RPM) is better than high (3500 RPM). but you could make do with a 6" high speed grinder if you had to. And since high speed 6" grinders are generally lots cheaper than 8" low speed grinders, you could get by with something more like this if you had to, but be prepared for more frustration and a steeper learning curve than you'll have with the bigger low speed grinders.

Why is that? You may hear some people say that a high speed grinder will get tools too hot and they'll lose their temper, and that is indeed a concern with the high carbon steels that bench chisels for flatwork are made out of. (Lathe chisels and gouges used to be made out of high carbon steel also). However, modern gouges for turning are almost all made of HSS - high speed steel, the same stuff you'll find on router bits and the like. It's designed to get hot and you would have to be consciously trying really hard to ruin its temper because the point at which HSS begins to lose its temper is around 1000 - 1100 degrees (F), well beyond the "blueing" of the steel that occurs around 600 degrees.

So, what's the problem with a high speed grinder then? Put simply, they just eat away steel that much faster and the compound shapes needed to properly put what we call a "fingernail profile" on a gouge are harder to learn when you have to move through what is at first an unnatural series of movements that much faster. Not impossible by any means, just a little more challenging!

The Tormek and Worksharp that /u/KiltedCajun mentions are totally unnecessary for sharpening woodturning tools imo. Would I use them if I had them? You bet! It's always fun to play with a new toy. However, I'd be willing to bet he had them for other things first and didn't buy them specifically with turning in mind.

One thing that most turners do wind up getting is the Wolverine sharpening jig- it's essentially a two-sided grinding jig that goes under both sides of you grinder and makes getting a repeatable grind shape so much easier. It's gotten to the point where it's damn near ubiquitous in the turning world. Take a turning class anywhere from Rockler to community college to the top art schools and you'll see a Wolverine jig. More about those- base unit and vari-grind gouge attachment. As you can see, these will add to as much, if not more than, the cost of your grinder, but they aren't essential if you've got the patience to learn how to freehand. That being said, I can freehand sharpen if I have to but I'm not giving up my Wolverine anytime soon.