Counterboring valve seat ring bores

RDS Counterboring Tools

The RDS turning device can be used to turn out the blind bore provided in the cylinder head to accommodate a valve seat insert.


Specifications RDS1 RDS2
  Bore diameter 20-60mm 35-90mm
Feed motions    
  Rotary motion By hand By hand
  Vertical motion 0,05mm/rev 0,05mm/rev
  Horizontal motion 0,05mm/rev 0,05mm/rev
  Length 95mm 150mm
  Width 65mm 100mm
  Height 260mm 280mm
  Net weight 1,35kg 3.1kg


The Hunger RDS is designed to precision machine the seat ring bores in cylinder heads to produce smooth and closely fitting contact surfaces for oversize seat inserts.


The RDS is equipped for counterboring as well as for facing the bottom of seat ring bores in a lathe-type action with a single point carbide cutter. The RDS is aligned in centerline with the valve guide by means of a pilot which is locked in the valve guide. An universal steady stabilizes the RDS against lateral displacement.
Pilots and steady furnished with Hunger valve seat refacing tool also suit for the corresponding RDS tool.
The built in feed gear mechanism for automatic longitudinal and cross feed of the single point cutter eliminates the need for multiple cutter sets and other accessories.
An adjustable stop for the tool slide permits quick selection of the proper sized bore diameter.

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