Technical Nomenclature Differences
The primary functional shift in this tool code is the directionality of the cut:
TTIL: The "L" explicitly indicates a Left-Hand cutting tool holder. While a right-hand tool (TTIR) moves toward the spindle when mounted on a standard front tool post, this left-hand variant is deployed when the CNC lathe spindle runs clockwise (reverse), or when the boring bar is flipped upside down on a rear tool turret to force machining forces downward into the machine bed for rigidity.
20: Dictates the physical metric Shank Diameter (20 mm).
IMC Group
+1
4C: Confirms it accepts an indexable insert with a 4.0 mm cutting width and features an integrated internal Coolant channel routing straight to the cutting edge to clear out chips from deep blind bores.
IMC Group
+1
T8: Dictates the toolholder profile's maximum groove depth capacity of 8.0 mm.
IMC Group
Side-by-Side Comparison
Parameter
TTIR 20 4C T8 (Previous Tool) 20TTIL 4C T8 / TTIL 20-4C-T8 (Current Tool)
Tool Direction Right-Hand (R) Left-Hand (L)
Shank Diameter 20 mm 20 mm
Insert Pocket Size 4.0 mm seat width 4.0 mm seat width
Coolant Feed Internal through-coolant hole Internal through-coolant hole
Max Depth (
) 8.0 mm 8.0 mm.