False! Carbide lapping advice

I have been grinding and lapping carbide tools for about 40 years. I have been given conflicting advice about slow grinding and lapping
carbide with diamond wheels. Whether using a plated wheel or a cast iron wheel charged with diamond I have found that the most common advice I have been given and also seen on youtube recently is wrong. But the advice I was first given turns out to be correct. For the best edge when using a slow speed grinder, such as a Leonard Grind-r-lap or an Accu Finish, the grinding should be such that the wheel surface moves away from the edge. Not into the edge. With the wheel moving away from the edge the part being ground will tend to be lifted from the table. This is a bit of a hassle but the edge will be better. When rough grinding I have the wheel moving into the edge but reverse the rotation when getting the final edge. I have been told many times that my method is wrong, that it will chip the edge. This has not been my experience. I get a better edge. Sharper and with no chipping. Not only do the tools cut better and last longer, which is the best test, but under a microscope the edge looks better. I just looked at some inserts I ground special for a grooving job using a very nice UNITRON metallurgical microscope at 600 x magnification. Wheel rotation into the edge rounds the edge slightly, while rotation away does not. And the carbide does not chip. Incidently, when I first started using a slow speed grinder it was a Leonard Grind-r-lap, and the instructions with the machine said to grind away from the edge when using diamond abrasive on carbide. I still use one of these machines. I bought it used years ago because it does such a good job and is so easy to use. I hope this helps somebody. Eric
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Thank You very much Eric for posting this! ;>) phil k.

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https://www.eaglesuperabrasives.com/typical-diamond-wheel-cbn-wheel-speeds/
I have some chipped, unbalanced diamond wheels. How slow is reasonable?
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