To be honest I have found that most of these carbide engraving cutter take the tip off far to easily, makes sense when you think about it as carbide is a sintered powder and has no grain as such.

Recently I have been grinding my own up from 6mm HSS drill blanks, don't last as long as carbide but once you have the D shape they cam be resharpened in about 2 minutes. Plus bit is you don't scrap a job because it takes the tip off 1 hour into a 3 hour job.

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8" x 3/4" all done with HSS tool.