Grommet Grinders

[wuboydonut]

Hey guys i tried looking through the forum but cant find much stuff, need some enlightenment from you all>

Ok so, i find it REALLY hard to remove grommets, especially ones which definitely need replacing. I tried it with awls, pliers and cutters, from the inside and outside of the racquet too.
Wondering how one go about using a grommet grinder, and are they effective and safe (for racquet) to use? i also notice 3mm and 4mm sizes, would i need both sizes just for badminton ??

Thank you all very much !

[maxout]

For badminton only use 3mm - turn left right left right (grinding action) until grommet is loose then remove