I have a few boxes of small 10mm triangular turning inserts that I have not been able to use because I have no holder for them. Making the holder isn't too difficult but, because they only have a tiny 2mm hole, I been puzzling how to hold the insert securely (an M2 screw would be obvious, but not all that strong).
I pinched this idea from some larger Iscar (?) tool bars and it seems to work well. The M5 grub screw has a eccentric 2mm pin turned on the end. The insert is locked down by 'undoing' the grub from underneath the tool thus both pulling the insert down and back.
It has the great advantage that the hex head does not get filled with swarf and there's no head to get in the way on top either.
[edit] The insert is sitting flat in the second photo - it's just the shadow that makes it look wonky
