Beadsmith 10-Piece Diamond 150 Grit Tip Drill Bits for Engraving, 2.35mm

didn't fit my drill, probably my fault as didn't check mm's but said fitted all or suchlike

These bits are way too long to be useful in the Beadsmith Micro Engraver. -- You'd think that the length wouldn't matter, but because of the way the "chuck" works, it totally does -- the bits are never centered perfectly, because they only receive pressure from one side -- with very short bits (like the one included with the micro engraver), it's not terribly noticeable, but with bits this long, they just wobble around, and the fine tips are completely wasted / useless.My super dull (and short) bit that was included with the micro engraver still works better than any of these. -- I'm going to consult a friend on cutting these bits down to a shorter length on his band saw (or perhaps another tool) before giving up completely, but I'm very sad that these bits don't work well with this tool.

Half the bits were milled poorly and are larger than advertised so do not fit in my miniature engraver. Also did not last long on the ones that did fit before the grit was completely gone (maybe 10 min on soft plastic with shallow engraving)

Three of the pieces were slightly thicker, and I had to grind them a little bit using my hand drill and sand paper to fit them into my micro engraver. One of them was a little bent, that made it unusable. So I got 9 for the price of 10, but that's O.K., since the whole set is rather cheap. Yeah, and too long for a microingraver, but it was easy to cut them to a reasonable size.

I have tried only one tip, it was slightly unbalanced for my battery power unit, it seems they would be ok for something that was somewhat slower RPM than my General