Answer
Jul 24, 2025 - 02:18 AM
For the PDT (Poltava) Expert CBN resin bonded stones, here are the recommended lapping powders based on grit size:
- 225 grit (100/80 μm) – Coarse→ Use F80 powder (200/160 µm) for lapping.
- 550 grit (40/28 μm) – Medium→ Use F120 powder (125/100 µm) for lapping.
- 1100 grit (20/14 μm) – Fine→ Use F220 powder (63/50 µm) for lapping.
- 1700 grit (10/7 μm) – Extra Fine→ Use F320 powder (28/20 µm) for lapping.
- 4000 grit (5/3 μm) – Ultra Fine→ Use F600 (10/7 µm) or F1000 (5/3 µm) powder for lapping.
As for the F400 powder (20/14 µm) — it’s typically used for lapping stones in the 10/7 μm range, and in some cases even finer stones like 7/5 μm, depending on the bonding and wear level.
Let me know if you’d like help choosing a custom progression or building your full set.
