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Products >> Boring Tools >> Boring Range .590"-8.000"


Boring Range .590"-8.000" (15mm-203mm)


Precision Vernier Dial

KAISER 309 & 310 boring heads are designed for precision production boring on machining centers, boring mills, transfer machines and high speed milling machines. Their fully enclosed, compact and rugged design allows reliable operation, even under extreme cutting conditions.

The KAISER 309 & 310 heads feature highly accurate and smooth micrometer adjustment precision. Each size of head is available with either inch or metric graduations which are easily read from a large dial. The adjustability of Series 310 heads is .0005"/Ø, .0001"/Ø with Vernier, or .01mm/Ø, .002mm/Ø with Vernier. Series 309 features .00005"/Ø, without Vernier markings!

The unique locking system prevents any diameter shift under locking action forces and maintains diameter under all cutting conditions, assuring of the highest repeatability. An additional feature is the simultaneous locking of the adjusting dial, preventing accidental adjustments. All tool carrier movement is strictly radial, making length corrections required on angular mounted boring cartridges unnecessary.

All insert holders are designed for use with positive rake indexable inserts. Self-centering, center-clamping screws are used, eliminating top clamps which obstruct efficient chip evacuation. Through spindle coolant capability is standard on all 309 & 310 heads.


A product of:

EWB Series 309 Finish Boring Flv

EWB Finish Boring Flv

EWN Finish Boring Flv

EWD Digital Boring Flv

Diameter Adjustments on KAISER Finish Boring Heads Flv

Series 309 EWB-UP (Ultra Precision) Boring Head - Boring Range Ø.984"-3.937" (Ø25-100mm)

The revolutionary new EWB-UP series sets new standards for boring head adjustment accuracy and balance quality.

Diameter adjustments in the sub-micron range and balance qualities of G 6.3 are requirements for tight tolerance bores
with maximum RPM’s.

Series 310 EW Small Diameter - Boring Range Ø.590"-.866" (Ø15-22mm)

2 boring heads with threaded connection (M6 & M10) suitable for high speed boring are easily adapted to carbide bars ø14mm and 5/8".

Series 310 Small Diameter

Series 310 EWB Auto-Balance & High Speed Boring Heads - Boring Range Ø1.260"-4.134" (Ø32-105mm)

9 different EWB boring heads which feature an integrated counter balance system to automatically offset tool carrier imbalance caused by diameter corrections. Speeds up to 6,600 SFM are obtainable and through the elimination of unbalance forces guarantees vibration-free finish boring.

EWB Boring

Series 310 EWB New Lightweight Aluminum Boring Heads - Boring Range Ø3.937"-8.000" (Ø100-203mm)

  • Automatic precision balance over entire work range

  • Combines clamping of tool carrier

  • Counterweight; will not change diameter setting

  • Same dimensions as program EWN

  • Smooth, play-free micrometer spindle with inch or metric graduations

  • Through spindle coolant

  • ISO standard insert pockets


Series 310 EWN Production Boring Heads - Boring Range Ø.787"-8.000" (Ø20-203mm)

Largest bore range of any system with nearly 50% overlap of each boring head by means of 3 different size insert holders. These tools can also be adapted for back boring by simply reversing the insert holder.

Can be used with the Smart Damper for deep hole boring utilizing our new damping extended reach shank.

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EWN Boring

Series 310 EWD Digital Precision Finish Boring Heads - Boring Range Ø1.614"-8.000" (Ø41mm-203mm)

The new KAISER Series 310 EWD precision boring head features absolute setting accuracy shown on a built-in digital display. The robust measurement system shows precise linear movement of the tool carrier permitting diameter adjustments of °.00005" or °.001mm. These boring heads utilize existing insert holders from program 310 EWN to allow an increased boring range and compatibility with existing special designs.

EWD Digital Boring


EWN technical info

EWN technical data
Auto-balance boring heads, Series 310 EWB, maintain perfect balance throughout the work range due to the integrated counter-balance mechanism. The counter-weight can only compensate for one size insert holder, so the work range is similar to EWN with Size 1 insert holder

Series 310 EWN boring heads are pre-balanced at one position only; the Mid range of the tool carrier travel with size 1 insert holder. Adjustment of bore diameter form this position and/or use of size 2 and 3 insert holders will require reduction of cutting speed values due to increased unbalance forces.