Allow me to join into this fine thread on fine wheels, and I'll disagree with nobody (for once <g>).
I have D-Way CBN wheels and am very happy with them. I bought my 180 grit beveled (rounded) edge from David Ellsworth's web site at a time some years ago when he and Dave Schweitzer had cooperated on the round edge wheel (for David's hollowing cutters). About a year later I bought Dave's 80 grit square edge wheel (with grit on the edge). My best guess is that I've had the 80 grit for about 3 years and the 180 a bit over 4 years. It could be longer on both, my aging mind loses track of time. I have seen no degradation in the wheels.
As to the grinders, my slow speed died about 2 years ago and I needed a new one quickly. Slow speeds cost an arm and a leg for good ones so I went to my local Loewe's and bought a Delta variable speed that was supposed to be 1800 rpm at the low end. I got nervous when I put a tach on it and found that it ran a bit above 2000 rpm with the CBN wheels on it. Turned out to be no problem, there was no significant heating from the extra speed and the face of the tool bevels is lovely. A plus came in when I realized that I could do heavy tool reshaping on the 80 grit wheel at top speed (@ 3400 rpm) without overheating.
Arbors and wheel widths were discussed. My Delta is designed for a 1" x 8" wheel with a 5/8" arbor, my D-Ways are 1 1/2" x 8" x 1" arbor. Dave provides bushings for the different arbor diameters, and also "shoulder drilled" bushings for grinders with short axles, but those are things you can make yourself if you choose to (and have the equipment).
One great advantage of the CBN wheel might be considered by some to be a disadvantage. I can finish grinding a tool, then hone it, then go to the kitchen and grab a beer, then sit back on my stool by the lathe and consider the piece I'm working on and where to cut next, and then get up and start the cut - and the grinder is still spinning down. And that even happened when I had only one wheel on the grinder (I was soaking my 80 grit as it had some buildup of junk from shaping the wrong metal).
Which leads me to the matter of questioning some opinions (I lied, but only gently - I'm questioning, not disagreeing). I've seen the paeans to the finer grits of CBN, and not only in this thread. Our good Robo Hippy has an excellent list of the grits, and has several grinders. My shop, as you can see in my avatar, is in my bedroom. My grinding station is behind my upper body, between the doorway and the tool box behind my right shoulder. Were I to offer advice on the grits I'd stick with the 180 (with rounded edge, for cutters) and the 80 for reshaping.
Let me modify that. I am a habitual honer. I love my Lacer 600 grit diamond slipstone, although it isn't cheap. I prefer a burr I raise myself with a hand burnisher. Perhaps there is an advantage to a very fine CBN wheel that leaves no burr, but I find that having jigs that exactly reproduce a bevel shape (be it using the Wolverine for a gouge or the direct angle of a skew or bedan or roughing gouge) allows one to use a light touch on the grinder for a fine edge with the 180 grit. One last thing - it helps to strop after honing (unless you want a burr) and a nice cowhide apron makes a nice strop that is always there <g>.
The CBNs are worth the price, but not all vendors make them the same way. I can vouch for D-Way, but can't fault any others as I haven't tried them. There are several ways to embed an abrasive (be it diamond or CBN) into a basic metal - and not all are equally consistent in life or consistency.
The ability to perfectly duplicate a grind because the wheel diameter (and shape) doesn't change saves a lot of tool steel as the "regrind" is really a "touch up" on the wheel. One loses some of the advantages of the CBN wheel if one doesn't use jigs that duplicate the grind. I'm a fan of my Geiger vertical solution set-up, but he doesn't sell it anymore. Most rigs allow for horizontal distance from the V socket, the GVS allows one to adjust both horizontal and vertical. BTW, no need to adjust both - but it is more convenient to have both settings.
Best, Jon
