I needed to grind a piece of HSS today and as I started my grinding wheel started to clog up. I stopped the grinder and found a wide streak of metal firmly embedded on the surface. I think I have ground something that had zinc plating or similar on it without realising. No problem, just get the mounted point diamond dresser and give it a quick skim. Half an hour later still hadn't found the dressing tool (it is a rarely used thing as I use inserts most of the time and have a CBN wheel for HSS touching up purposes).

In the process of searching for it I came across an old segmented diamond edged stone cutting disc that stopped working when the edge wore down. Since the sides still had some diamonds embedded I thought I'd give it a try. Laying it flat on the rest and sliding it across the wheel gave me a beautifully fresh and open face on the wheel with no sign of embedded metal. I will have to cut a segment out to make a more sensible tool now.

Martin C