Diamond tools are designed around the equipment they are used with. When you don't have the exact type of equipment, it is critical to still apply the correct operating RPM.
Improper RPM usage is one of the most common reasons that diamond tools stop working. Higher RPM leads to less torque, which means a higher risk of the tooling losing traction and spin out. Therefore, it's always safe to check what the optimal RPM is for the tool you are working with.
Grinding Wheels and Blades:
Below 7" in diameter, these tooling (and thus RPM) are designed for angle grinders. Any standard grinders will perform the job just fine. It is very important for both performance and safety reasons to pay attention to the max RPM that these tools can sustain.
| Diameter | Recommended RPM | Max RPM |
|---|---|---|
| 4" | 9,000 | 15,000 |
| 4.5" | 8,000 | 13,300 |
| 5" | 7,200 | 12,000 |
| 6" | 6,000 | 10,185 |
| 7" | 5,100 | 8,730 |
| 8" | 4,500 | 7,640 |
| 9" | 4,000 | 6,700 |
| 10" | 3,600 | 6,100 |
| 12" | 3,000 | 5,000 |
| 14" | 2,500 | 4,300 |
| 16" | 2,200 | 3,750 |
| 18" | 2,000 | 3,300 |
| 20" | 1,800 | 3,000 |
Core Bits:
Dry core bits are typically designed to be used with hand-held core drills, while wet core bits are designed for core drill rigs. There is more flexibility with core bits RPM, as equipments like hammer drills and gas-powered drills can work quite well for small diameter bits.
| Bit Outer Diameter | Dry Core Bits | Wet Core Bits | ||||
|---|---|---|---|---|---|---|
| Min RPM | Ideal RPM | Max RPM | Min RPM | Ideal RPM | Max RPM | |
| 1/2" | 4775 | 6364 | 7960 | |||
| 5/8" | 3820 | 5091 | 6368 | |||
| 3/4" | 3183 | 5307 | 4242 | |||
| 7/8" | 2728 | 3636 | 4549 | |||
| 1" | 2300 | 4775 | 6000 | 2387 | 3182 | 3980 |
| 1-1/8" | 2300 | 4430 | 6000 | 2122 | 2828 | 3538 |
| 1-1/4" | 2300 | 3820 | 6000 | 1910 | 2545 | 3184 |
| 1-3/8" | 1736 | 2314 | 2895 | |||
| 1-1/2" | 1600 | 3183 | 5000 | 1592 | 2121 | 2653 |
| 1-5/8" | 1469 | 1958 | 2449 | |||
| 1-3/4" | 1600 | 2728 | 5000 | 1364 | 1818 | 2274 |
| 1-7/8" | 1273 | 1697 | 2123 | |||
| 2" | 1200 | 2387 | 5000 | 1194 | 1591 | 1990 |
| 2-1/4" | 1200 | 2122 | 5000 | 1061 | 1414 | 1769 |
| 2-1/2" | 1200 | 1910 | 5000 | 955 | 1273 | 1592 |
| 2-3/4" | 868 | 1157 | 1447 | |||
| 3" | 800 | 1592 | 5000 | 796 | 1061 | 1327 |
| 3-1/4" | 735 | 979 | 1225 | |||
| 3-1/2" | 800 | 1364 | 5000 | 682 | 909 | 1137 |
| 4" | 700 | 1241 | 5000 | 597 | 795 | 995 |
| 4-1/4" | 562 | 749 | 937 | |||
| 4-1/2" | 700 | 1103 | 5000 | 531 | 707 | 884 |
| 5" | 700 | 993 | 3500 | 477 | 636 | 796 |
| 5-1/2" | 434 | 579 | 724 | |||
| 6" | 600 | 828 | 2500 | 398 | 530 | 663 |
| 6-1/4" | 382 | 509 | 637 | |||
| 6-1/2" | 367 | 490 | 612 | |||
| 7" | 341 | 455 | 569 | |||
| 8" | 298 | 398 | 498 | |||
| 9" | 265 | 354 | 442 | |||
| 10" | 239 | 318 | 398 | |||