Accuromm Central Europe

A tool engineering company that supports all work related to tools

The definitive version of hole machining!

High-precision boring with a machining center

Boring holder with optimal guide pad

Cutting force optimized guide pad arrangement

Easy operation for fine adjustment

Dedicated setting gauge also provided

Amazing facts!

── Introducing ideas and technologies ──

The GB tool consists of 2 leading edges and 1 finishing edge.
The optimal guide pad arrangement, which matches the cutting resistance, self-guides the self-machined hole to achieve excellent roundness and straightness during the boring machining of the bore hole on a machining center.
Furthermore, the unique fine-tuning mechanism enables easy setting.

GB tool configuration

Processing steps

① Hole entry (mouth) processing with short tool

② Deep hole processing with long tool

This is the point!

Optimal guide pad placement for cutting resistance

Excellent!

Cutting resistance build-up

Guide pad supresses tool displacement

Stable machining accuracy

This is the point!

Fine adjustment with easy operation - Single action type leading edge

Excellent!

Adjustment method

① Fix the insert with the clamping screw

 

② Adjust the diameter with the diameter adjustment screw

This is the point!

Fine adjustment with easy operation -
Double action type finishing edges

Excellent!

Adjustment method

① Fix the insert with the clamping screw

 

② Adjust diameter with the diameter adjustment screw
③ Adjust backtaper with the backtaper adjustment screw

Dedicated setting gauge

  • Leading edge: cutting edge diameter adjustment
  • Finishing edge: cutting edge and back taper adjustment

Development / product concept

“Current status and challenges”

  • In order to reduce investment and support high-mix multi-product production, it was necessary to shift from a specialized machine to a general-purpose machine.
  • However, the general-purpose machine had problems with positioning and straightness, because it did not have the support of a dedicated machine when machining a bore hole

“Development points”

  • “GB TOOL” self-guides the machined hole using an optimal arrangement of guide pads, thereby reducing displacement of the cutting edge and enabling high-precision drilling on general-purpose machines, thereby realizing “investment reduction” and “multi-product” compatibility.

Processing example

Tool name

GB tool (guide pad boring tool)

Machining work

Cylinder head (cam hole)

Work material

JIS AC2C-T6 / ISO Al-Si5Cu3Mn

Tool diameter

ø26 mm

Cutting conditions

Spindle speed: S = 2957 min-1
Cutting speed: Vc = 260 m/min
Feed: f = 0.1 mm/rev

Coolant

Internal coolant (emulsion 10%)

Machining accuracy

Satisfies the required accuracy

Roundness: 3 µm
Coaxiality: 5 µm

(see right)

Required accuracy

Roundness / coaxiality

Roundness: 3 µm
Coaxiality: 5 µm

Specification

Tool name

GB tool (guide pad boring tool)

Standard conditions

Cutting speed: Vc = 200-300 m/min
Feed: f = 0.1-0.2 mm/rev
Internal coolant supply
Required coolant concentration: 5% or more

Compatible diameter

ø16 mm and up (single action)
ø22 mm and up (double action)
max ø50 mm

Applicable processes

Cylinder head cam hole, steering housing

Applicable materials

Aluminium (high volume production) or cast iron (low volume / prototype production)

Concentricity

8 µm

Surface roughness

3.2 Rz

Processing diameter

IT7