I've posted this on a couple of other discussion boards recently - maybe I should just cut and paste to save myself some time...
I have been using a Wolverine on a grinder for 15 years now, and a grinder freehand since I started turning 17 years ago. A few years ago I bought a used Tormek at a great price thinking to use it for my flat work tools. It just sat there. I did sharpen my pocket knife with it, but it was a very expensive way to get that job done.
When Tormek came out with their bench grinder attachment, I decided to give it a try. I am now converted to Tormek for my turning tools.
I use the bench grinder to shape the tools, and then maintain them on my Tormek. There are several benefits to this. First, I grind away a lot less steel. Even though I consider myself pretty good with a grinder, the Tormek still takes less steel away when I use it. This might be inconsequential to some, and maybe in the scheme of things it might not be a tipping point all by itself.
As far as speed is concerned, I think it is a non issue for the vast majority of turners. With just a little bit of practice, I can sharpen an edge just as fast with the Tormek as I can with the Wolverine. Wait, practice? You have to figure out how to use this thing? People have to figure out how to use the Wolverine too. I know. I had to do it, and I have taught well over a thousand turners in person how to use this tool. Clamping a Tormek jig onto a gouge is no slower than clamping a Wolverine jig onto a gouge. And once the profile is established, the sharpening is accomplished in a matter of seconds. But wait, there's more!
Two huge benefits to anyone using this system for turning tools are health and safety related. In the first place, the amount of silica and metal in the air is reduced to practically zero by switching to the wet grinding method Tormek uses. I wear an air helmet when I turn, but still, I get that stuff in my lungs just about every time I grind a tool. Reducing my grinding to initial sharpening lessens that greatly. The second is the issue of sparks. I have never had a problem with sparks, but it is always a concern when wood chips and dust are concerned. Wet grinding equals no sparks, period. And then, there is the benefit that my tools have a sharper edge. I noticed an improvement in the surfaces I was getting as soon as I started using the Tormek. I start sanding bowls, and will continue to start sanding with 80 grit. But now it goes even faster.
One very large benefit to me that not everyone will require is the portability of the Tormek. I have demoed and taught in more places than I can remember, and often, the sharpening setup leaves somewhat to be desired. I have been greeted with aluminum coated wheels from a previous user in a common shop, improperly set up Wolverines, poorly built home made knock offs, wheels too fine and loaded with metal, no wheel dresser, etc. The list goes on. Now I can grab my Tormek and go very quickly and easily, and I know exactly what I have to use. It has been with me on two demos already.
One thing I did was to add the black wheel. I don't think it grinds any faster on exotic steel, such as my Thompson tools, but it sure seems to last a lot longer between dressings. Maybe it lasts longer because it grinds faster. I don't know. That is an issue for engineers to ponder. It was not hard to change my tools over, while retaining my own particular grinds. Some of the settings in the book worked for some of my tools, and for some, I had to tweak it just a bit. But once that is done, it is done. I never thought this would be a tool for me, but I have really been impressed with how it works.
I used the Tormek exclusively for my own tools while I was in Hartford demonstrating for Robust. I did walk down to their booth when Doug Thompson handed me a brand new skew and did initial shaping on their dry grinder, but then finished it up on my Tormek.
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I don't get much mess either. In both cases water is involved, but a few drips of water are as nothing in my shop.