How to find the right Internal Grooving Inserts AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Internal Grooving Inserts
- Minimum bore diameter
- The bar or holder's rated minimum bore must be smaller than your bore, with clearance left for chip evacuation. Below the minimum, the bar's back side contacts the bore wall.
- Overhang to diameter ratio
- Keep overhang as short as possible. Steel bars handle only short overhangs relative to bar diameter. Use carbide-shank or damped bars for deeper bores. Grooving forces are high and radial, so deflection and chatter rise steeply with overhang.
- Small-bore system choice
- Use dedicated small-bore solid-carbide or mini insert systems for very small bores, such as Horn Supermini or Sandvik CoroTurn XS. Use exchangeable-head or insert bars for larger bores, such as Sandvik CoroCut MB. Standard insert pockets do not fit small bores, and mini systems keep rigidity there.
- Coolant through the bar
- Prefer bars with internal coolant for blind bores and deep grooves. Coolant flushes chips out of the bore, preventing recutting and jamming.
- Insert width, profile and grade
- Match width, corner radius and ISO grade as for external grooving, choosing sharper, lower-force geometries for long overhangs. Lower cutting force reduces deflection inside the bore.
- Groove depth versus bore
- The tool's maximum radial depth must cover your groove depth at your bore size. Small-bore tools have limited reach, which sets the deepest groove possible.
Brands that matter
- Paul Horn: The Supermini and Mini systems are a reference for small-bore internal grooving.
- Sandvik Coromant: CoroCut MB for internal grooving, plus CoroTurn XS for small bores.
- Iscar: Wide internal grooving range, including small-bore tools.
- Kennametal: Internal grooving bars and inserts in its grooving systems.
- Simturn: Specialist in small-bore internal grooving and boring tools.
- Vargus: Mini internal grooving systems alongside its threading ranges.
What to avoid
- Choosing a bar by bore size alone without checking overhang capability.
- Steel bars at long overhangs, which chatter.
- Bars without through-coolant for deep or blind-bore grooves.
- Wide inserts at long overhang when several narrow plunges would cut with less force.
Questions
Why does my internal groove chatter when external grooving is fine?
Internal tools are limited by bore size, so overhang relative to bar diameter is much higher. Shorten the overhang, use a carbide or damped bar, or switch to a sharper, lower-force geometry.