The two new wheels he bought run worse, the one I tried today was from radiac (60-k8-v1) it didn't glaze over but did burn.
I think the coolant is a major factor
do ya'll agree
My obsolete 1970's Landis handbook suggests using the 60 grit wheels for finishing rather than heavy stock removal on low hardness steel shafts. The 60 grit wheel in a less durable aluminum oxide is recommended when working with tool steels.
In the equivalence chart in the handbook it does not look like the manufacturers could agree on what the numbers mean. They are using different recipes for the aluminum oxide abrasive. So the numbers quoted here for Norton wheels may not be applicable to Radiac wheels.
Could you give the Radiac distributor a phone call and ask what they recommend for your work? They will need to know the surface hardness, how much material is to be removed, and the required surface finish.
The brown or gray-blue aluminum oxide wheels have titanium dioxide added to the aluminum oxide to make the abrasive more durable and resistant to shock. The white wheels have abrasive grains that are less durable but remain sharp while grinding.
The coolant serves as a lubricant and as a heat transfer fluid. There is a optimum viscosity for a given abrasive grain size and wheel speed. If it is too viscous the wheel skids. If it is too thin the coolant no longer lubricates.
When the mix is selected carefully there is reduced horsepower required for grinding and reduced heat in the part. Somewhere on the Benz oil website there is a viscosity selection chart and a detailed explanation. I could not find it a few minutes ago but it is there somewhere. If you see oil floating in the coolant tank it may mean that the water-oil emulsion has separated. Your coolant at that point is no longer a lubricant.
The sludge in the coolant tank may also be blocking the plumbing and reducing the flow to the wheel nozzle.