Grooving Inserts — Catalog by Width and Manufacturer

Compiled 2026-04-04 · 40 chunks, 12 posts · grooving · inserts · lathe-tooling · parting · turning · indexable-inserts

Summary

Grooving inserts are indexable carbide cutting tools designed for machining grooves, parting off workpieces, and cutting O-ring seats on lathes. Unlike solid [[grooving-parting]] tools, these inserts clamp into holders and can be rotated or replaced when worn. Width is the critical specification — ranging from 0.031" (0.8mm) for precision O-ring grooves up to 0.315" (8mm) for heavy parting operations. Insert geometry, chip breaker design, and grade selection directly impact performance across different materials from [[aluminum-6061]] to [[inconel-718]].

Insert Width Classifications

Narrow Width (0.031" - 0.062")

Micro 100 QID Series

  • QID-031: 0.031" width for precision O-ring grooves
  • QID-047: 0.047" width for small seal grooves
  • QID-062: 0.062" width for general narrow grooving
  • Grade: Uncoated carbide, sharp edge geometry
  • Applications: Medical devices, hydraulic fittings, precision seals

Sandvik N331.32 T-Series

  • N331.32-080T25: 3.15mm (0.124") width
  • N331.32-101T32: 4.0mm (0.157") width
  • N331.32-127T38: 5.0mm (0.197") width
  • Grades available: CM (uncoated), DM (CVD), EM (PVD), FM (cermet)

Standard Width (0.093" - 0.187")

Sandvik N331.32 S-Series

  • N331.32C-080S27: 2.7mm (0.106") width, 80mm diameter compatibility
  • N331.32C-100S32: 3.2mm (0.126") width, 100mm diameter
  • N331.32C-125S40: 4.0mm (0.157") width, 125mm diameter
  • N331.32C-160S40: 4.0mm (0.157") width, 160mm diameter

Iscar GRIP Series

  • GRIP 3008Y: 3.0mm (0.118") width
  • GRIP 4008Y: 4.0mm (0.157") width
  • GRIP 5008Y: 5.0mm (0.197") width
  • Features: Sharp cutting edge, positive rake angle

Wide Width (0.197" - 0.315")

Sandvik R331.32 Series

  • R331.32-305R63: 5mm (0.197") width
  • R331.32-202Q40: 8mm (0.315") width for heavy parting
  • Available in KM (PVD coated) and RM (cermet) grades

Speeds and Feeds by Material

Steel ([[4140-steel]], [[1018-1045-steel]])

Manufacturer recommendations:

  • Surface speed: 400-600 SFM
  • Feed rate: 0.002-0.008 IPR
  • Depth of cut: Full insert width

Shop floor experience:

  • Start at 300 SFM for 4140 heat treated (>30 HRC)
  • 0.004 IPR feed works well for most applications
  • Use flood coolant or high-pressure coolant for deep grooves >0.5" depth

Stainless Steel ([[304-stainless]], [[17-4ph-stainless]])

Parameters:

  • Surface speed: 250-400 SFM (reduce for [[work-hardening]] materials)
  • Feed rate: 0.003-0.006 IPR
  • Depth of cut: 0.75 × insert width maximum

Critical notes:

  • Never dwell in stainless — maintain constant feed
  • Sharp insert geometry essential to prevent work hardening
  • For 17-4PH condition H900: reduce speed to 200 SFM

Aluminum ([[aluminum-6061]], [[7075-aluminum]])

Parameters:

  • Surface speed: 1200-2000 SFM
  • Feed rate: 0.006-0.015 IPR
  • Depth of cut: Full width possible

Shop considerations:

  • Built-up edge is primary concern — use sharp, uncoated inserts
  • Air blast sufficient for cooling
  • Higher feeds prevent chip welding

Inconel ([[inconel-718]])

Challenging material requiring specific approach:

  • Surface speed: 150-250 SFM maximum
  • Feed rate: 0.001-0.003 IPR (maintain constant feed)
  • Depth of cut: 50% of insert width
  • Essential: Flood coolant, rigid setup, sharp cermet grades

Insert Grade Selection Guide

Uncoated Carbide (Grade C)

  • Best for: Aluminum, brass, plastics
  • Characteristics: Sharp edge, no coating buildup
  • Limitations: Lower wear resistance

CVD Coated (Grade D)

  • Best for: Steel, cast iron general machining
  • Coating: TiCN/Al2O3 layers
  • Benefits: Wear resistance, chemical stability

PVD Coated (Grade E/K)

  • Best for: Stainless steel, titanium
  • Coating: TiAlN typically
  • Benefits: Sharp edge retention, heat resistance

Cermet (Grade F/M)

  • Best for: High-speed finishing, difficult materials
  • Characteristics: TiC/TiN matrix
  • Applications: Inconel, hardened steels

Toolholder Compatibility

Sandvik System

  • R331.32 holders for external grooving
  • N331.32 holders for internal grooving
  • QD system for quick-change applications

Iscar GEHIR System

  • GEHIR holders accommodate GRIP inserts
  • Available in right-hand and left-hand orientations
  • Modular system for various shank sizes

Micro 100 Holders

  • QID holders for ultra-narrow inserts
  • Carbide construction for rigidity
  • Coolant-through capability available

Common Problems and Solutions

Chatter and Vibration

Symptoms: Wavy groove surface, loud cutting noise, premature insert wear Causes: Insufficient rigidity, incorrect speeds Solutions:

  • Reduce overhang — use shortest possible toolholder
  • Increase feed rate to maintain chip load
  • Check for spindle bearing wear
  • See [[chatter-vibration]] for detailed diagnosis

Insert Chipping

Symptoms: Micro-chips on cutting edge, poor surface finish Causes: Interrupted cuts, hard spots in material, excessive speed Solutions:

  • Reduce cutting speed 25-50%
  • Increase feed rate to reduce heat per unit volume
  • Switch to tougher grade (uncoated vs. coated)

Built-up Edge (BUE)

Symptoms: Material welded to insert, rough groove walls Materials: Primarily aluminum, low-carbon steel Solutions:

  • Increase cutting speed significantly
  • Use uncoated, sharp geometry inserts
  • Apply cutting fluid or increase flow rate

Shop Floor Tips

Insert Indexing Strategy

Most machinists rotate inserts before they're completely worn. "I typically index when I see the first sign of flank wear rather than waiting for chipping — you get more consistent finishes this way," reports one forum user.

O-Ring Groove Precision

For hydraulic applications requiring ±0.001" groove width tolerance:

  • Use 0.031" inserts even for 0.062" grooves (make two passes)
  • Spring pass at full depth improves dimensional accuracy
  • Measure groove with pin gages, not calipers

Coolant Application

High-pressure coolant (300+ PSI) dramatically improves tool life in deep grooving operations. One machinist reports: "Switched from flood to high-pressure and doubled insert life on 0.5" deep grooves in 4140."

Programming Considerations

  • Program dwelling moves carefully — inserts can weld in place
  • Use G04 (dwell) sparingly, prefer continuous motion
  • Retract quickly to prevent heat buildup
  • [[grooving-parting]] — Complete guide to grooving and parting operations
  • [[turning-basics]] — Fundamental lathe operations and setup
  • [[insert-selection-guide]] — General principles for insert selection
  • [[cnc-lathe-setup]] — Setup procedures for CNC lathe grooving
  • [[tool-wear-diagnosis]] — Identifying and preventing insert wear
  • [[work-hardening]] — Managing work-hardening materials like stainless steel