NPA 36/2020

New Reinforced SUMOGUN Drill Bodies for Better Torsion Force Resistance and Increased Machining Parameters


The only gundrill in the market with exchangeable drilling heads, as well as exchangeable shank drivers, has been modified with a new reinforced steel body with better resistance to torsional forces, which allows increased table feed

In August 2013, ISCAR introduced the SUMOGUN MNCNT family, which is produced from tubes (NPA 31-2013).
Following many changes, ISCAR is now introducing the SUMOGUN MNSNT family of gundrills made with reinforced steel bodies, which feature much better resistance to torsion forces and allow higher table feeds, thus better productivity. The new MNSNT will cover the range up to 400 mm length. The MNCNT will continue to be available for longer tools.

ISCAR continues to expand the drill length options above 12xD depth to diameter ratio, in a diameter range of 10 to 25.9 mm and to maximum total length of 400 mm, as well as for Ø10 mm-Ø14.5 mm diameters with flute length of 200 mm and Ø13 mm-Ø14.5 mm diameters with flute length of 250 mm.

  • The SUMOGUN features two straight flutes carrying the standard SUMOCHAM drilling heads
  • All drill bodies feature straight coolant holes
  • Exchangeable shank drivers – more economical and versatile system
    (the rear threaded connection enables attaching different standard shank types)
  • May be used on standard horizontal milling centers, lathes, and multi-task machines
  • Shank face contact and fine pitch thread connection provide very small runout

The SUMOCHAM drilling heads are fully effective, which enables drilling at much higher table feed rates (2 to 5 times more than standard brazed gundrills) when compared to most other gundrills available in the market.

SUMOGUN MNSNT enables replacement of the drilling head inside the machine – there is no need to remove the drill for head indexing. A polyamide plastic key is available for clamping and removing the SUMOGUN head.

The SUMOGUN provides end users with the ability to clamp different head geometries and grades, according to the material and application.

Specially tailored SUMOGUN drills will be supplied on request.

Indexable SUMOCHAM Inserts and Modular Shank Gundrills
(1) Do not mount smaller drilling heads than the specified range of the drill body
(2) Cutting diameter maximum
(3) Torque key size (4) Seat size code
(5) Master insert identification

Drill Penetration Instructions on Milling or Turning Machines

  1. Drill a pilot hole 0.5xD deep with a short drill in the same diameter as for the SUMOGUN drill.
  2. Enter the pre-hole at slow speed, feed, and 50 RPM until 1-2 mm before reaching the bottom.
  3. Activate the cooling system and increase rotation speed to recommended drilling speed, maintain for 2-3 seconds, then continue at recommended drilling feed. No pecking is required.
    Apply maximum possible coolant flow rate.
  4. After having reached the required depth, reduce speed to 50-100 RPM while exiting from the hole.

Note: The following procedure (1-4) is recommended for up to 400 mm hole depths using MNSNT …-400… drills.
For hole depths between 400 up to 800 mm, use MNCNT …-800… drill only after reaching 400 mm depth with an MNSNT …-400… drill.

When drilling with ICP/K insert, it is most recommended to use double margin inserts (TCP/K – 2M) both for main hole and pre-hole drilling.

Pre-hole 1xD deep for centering
Slow rotation and feed while entering the pre-hole
Maintain for 2-3 seconds and activate the cooling
Continue drilling at recommended cutting conditions

Machining Conditions for MNSNT
*Mandatory use of emulsion or oil when drilling

Pressure and Coolant Flow Rate for SUMOGUN
Q l/min
P bar
Milling and Turning Machines
SUMOGUN Drilling Range
Drilling Diameter

The NPA36-2020's pdf file: View (PDF) or Download (ZIP)
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