Diamond grinding wheels use diamonds as an abrasive to grind extremely hard materials. Industrial diamonds are ground into a powder for use in grinding and polishing applications, this diamond powder is mixed with a resin bond to create a layer of diamonds and bonder on a metal core to sharpen hardened scissors, these scissors are heat treated and run from 54 to 62 HRC, hardness Rockwell C scale. Diamonds may be plated to a wheel core, they tend to be a course diamond, these type of wheels are not good when you have to remove a lot of metal, they are slower to cut and the blade gets to hot so that you can't touch it.
This picture shows sharpening hardend beauty shears blade on Diamond resin bond wheel. This wheel shown is 800 grit.
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