On 2017-05-24 8:09 AM, Norm Wood wrote:
> I've previously tried 45 micron diamond
> compound placed on an iron plate for flattening the backs of chisels and
> plane blades.  I remember it working just 'OK'.  It was slow and I
> eventually switched to the blue zirconia alumina belts

I haven't tried the diamond compounds, but the blue zirconia belts glued 
to 1/4 inch glass are tremendous for flattening chisels. I'm using 50, 
80 & 120 belts. They last and last. Just vacuum off the swarf from time 
to time.

FWIW
Don

-- 
The harder they come, the bigger they fall - Ry Cooder