The first video
mainly shows how to build a metal jig for holding the angle grinder in an engineering vice, after which various sharpening and wire brushing operations are carried out using this set-up.
It looks impressive but I remember hearing several scare stories about grindstones and grinding disks which disintegrated with quite destructive effects when not used as intended.
Are there really suitable disks available for angle grinders, on which the sides of the disk can safely be used for grinding metal objects?
The second video
Shows a more heavy duty bench mounted setup also with a thin, large diameter disk, which seems to work well for grinding with it's flat face, rather than the edge.
Which, if any of these methods are considered reasonably safe?
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