CBN - What grit?

[Les Symonds]

I'm getting a CBN wheel, at last. What's the knowledge out there about what #grit to use?
Les

[GBF]

What grits do they come in Axminster are doing one but it seemed very course

[Les Symonds]

The trouble I'm getting, George, is that there's a lot of contradictory info out there. Toolpost don't list the grit in a numeric system, but have extra fine, fine, standard and coarse, whereas most of the American import stuff on ebay has 80, 180 and 240 grit as options. Difficult to make reasoned comparisons.
Les

[Eric Harvey]

I think if I were ever to buy one I`d go for the finest grit possible

[Paul Hannaby]

I have one of the standard Optigrind CBN wheels from the toolpost and that is equivalent to 180 grit. It takes off metal plenty fast enough for my liking so I wouldn't want a coarser grit wheel. Mine is fitted to a slow speed 8" grinder so in theory it should grind a little slower anyway (although the peripheral speed on an 8" grinder will be higher than an equivalent 6" wheel).

[Les Symonds]

I have one of the standard Optigrind CBN wheels .....

...thanks for that info, Paul. Out of interest, what width of wheel do you use....I've been advised to buy the 40mm, but I'm not sure that I can justify the added expense.
Les

[Paul Hannaby]

Yes it's the 40mm wheel. Defnitely better when using things like the gouge jigs that involve sideways movements.