Diamond Core Bit Recommended RPM

Core Bit Size	Rec. Min RPM	Rec. RPM	Rec. Max RPM
1 Inch	2380	3180	3980
2 Inch	1190	1590	1990
3 Inch	790	1060	1320
4 Inch	590	790	990
5 Inch	477	636	790
6 Inch	390	560	660
7 Inch	340	450	560
8 Inch	290	390	500
9 Inch	260	350	490
10 Inch	230	310	400
12 Inch	200	260	330
14 Inch	170	220	280
16 Inch	150	200	250

 

How to find the right RPM
Start off with the recommended RPM on the table you see above. From there, you will need to adjust to different variables. Different types of aggregate will need different speed, pressure, water, etc. A good operator will be able to feel the right speed and pressure to use. It takes skill and experience to tell.

If the drilling speed is too high, the bit will glaze over the diamonds preventing it from drilling.

If its too low, the drilling will take far too long.

Adjust accordingly.

If you do find the bit is glazed over, but there is still segment left, take the bit out of the hole and drill into some soft, abrasive cinder block to open up new diamonds.

For drilling through rebar, do not apply additional pressure. Apply the same amount of of pressure and do not force the bit into the drill.

Any questions or comments please feel free to call us at 800-618-5000.