drill more than 4000 holes G1/2 diamond glass core drill bits

MODEL: ZR-002

DIAMETER: 4mm-120mm

LENGTH: L75,L85,L95

C-grade bronze sintered diamond glass drill bits, with 1/2 GAS, length 75mm,85mm or 95mm, drilling more than 4000pcs holes, needing to be sharpen by manual after some times. 

Details: 

1. Bronze diamond glass drill bits are suit for all kinds of 4-19mm thickness glass;

2. Pls note: we suggest that working speed 3000-3500rpm for Ø4-Ø42,2000-2500rpm for Ø45-Ø70 and 1000-1500rpm for Ø70-Ø100 is best.

3. During the working, pls ensure the drill bit is cooling by water from inner and outside. If the drill bits are not sharp enough after some time, pls use 80-100# white corundum wheel to sharpen it then it can work again.

4. OEM is acceptable.