Insert, MRMN-200-M

The BPS253-CVD coating on these is holding up way better than the uncoated inserts I was running before — no chipping even on interrupted cuts in cast steel. Finishing passes leave a clean surface, and I've been pushing them into light roughing without any trouble.

Swapped these onto my lathe for a run of cast steel shafts and the interrupted cuts barely phased the edge. The CVD coating on the MRMN-200-M seems to handle both my finishing pass and the rougher ones without chipping.

The BPS253-CVD coating really holds up on continuous steel cuts — I ran a full batch of 4140 without any chipping on the tip. Finishing passes came out clean, and it still handled a few interrupted cuts without complaint.