WC is an 80° trigon (negative rake) insert family with strong, stable cutting edges — preferred for steel, alloy steel, and cast iron at high material removal rate. The negative rake geometry handles higher cutting forces and produces more stable chip evacuation, which matters on tough materials. SP is a 55° positive trigon (positive rake) insert family with sharper cutting edges and lower cutting force — preferred for stainless steel, aluminum, low-carbon steel, and thin plate work. For 2D shallow drilling on steel, use WC. For stainless / aluminum, use SP. Both are ISO 1832 standard.

2D depth ratio is the simplest, most rigid, and most forgiving drill geometry. It works for shallow plate drilling, cross-holes, and flat drilling where the hole depth is no more than 2× the drill diameter. The short drill body has excellent rigidity, lower chip evacuation demands, and lower coolant pressure requirements (7-15 bar). For deeper holes, choose 3D/4D/5D — but those require higher coolant pressure, more rigid setups, and have more chip evacuation risk. Pick the smallest depth ratio that fits your deepest hole.

Yes. All BEYOND WC 2D indexable U-drill bodies in this collection (C20 / C25 / C32 / C40 shanks) have through-body internal coolant channels that run from the shank end to the insert pocket. For steel, internal coolant is recommended at 2D (7-15 bar for small shanks, 12-18 bar for heavy). For cast iron, internal coolant is optional — cast iron produces dry chips, and flood coolant is sufficient. For 3D/4D/5D deeper ratios, internal coolant is mandatory.

Yes. All BEYOND WC 2D drill bodies follow ISO 1832 standard for WCGT (80° trigon ground) and WCMT (80° trigon molded) inserts. Cross-brand equivalents from Korloy, Mitsubishi, Sumitomo, and Sandvik will fit the same pocket. The only check needed is IC size (3.97 / 4.76 / 5.56 / 6.35 / 8.0 mm) and matching insert thickness. For grade selection, see the 8-brand grade cross-reference.

General rule: shank diameter should be at least 70-80% of the cutting diameter for rigidity without over-stressing the spindle. For 15-22mm drill, use C20 / C25 shank. For 22-30mm drill, use C25 shank. For 26-40mm drill, use C32 shank. For 38-60mm drill, use C40 shank. Bigger shank = more rigid setup but heavier spindle load. The full shank × insert cross-reference is in the table above.

WCGT inserts are precision-ground (tolerances ±0.025mm) — preferred for high-precision drilling where hole tolerance and surface finish matter. WCMT inserts are precision-molded (tolerances ±0.13mm) — lower cost, suitable for general production drilling. Both share the same 80° trigon negative rake geometry. For grade selection, see the 8-brand grade cross-reference. For material-based selection, see the insert-by-material pillar.