What is "stacked up" here? I don't understand as well what is "Abrasives"...
The same abrasives that I use on my big machines, they are an abrasive that is stacked up, so the abrasive itself breaks down and exposes new sharp edges.
To stack, or stack up, something such as boxes, cans, planks, bricks or whatever it may be, is to make a pile of them by placing one on top of another. The idea in this instance is that the abrasive grit is in layers, so that as the top layer wears down a fresh layer is exposed.
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To stack, or stack up, something such as boxes, cans, planks, bricks or whatever it may be, is to make a pile of them by placing one on top of another.
The idea in this instance is that the abrasive grit is in layers, so that as the top layer wears down a fresh layer is exposed.