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NPA 18/2019


Drill Diameter Adjustment Shims for TRIDEEP Gundrills

ISCAR is adding new sets of shims for TRIDEEP gundrills to allow easy and fast adjustment of drill diameters and help minimize the need for special gundrill tools.

A new range of shims has been added to the TRIDEEP line to enable diameter increases of 0.01mm up to 0.1mm on the existing standard gundrills, which are available in a diameter range of Ø12 up to Ø28mm.

The shims need to be mounted under the guide pads which are assembled on the TRIDEEP gundrills.

  • The shims are designed to provide diameter adjustment ability on the standard TRIDEEP gundrills
  • Easy and fast adjustment in a range of 0.01 up to 0.1mm
  • Two sets are available with 5 shims each; this will provide the option of combining two shims to obtain the requested dimension and diameter enlargement
  • Accurate hole diameters that were only attainable with the use of special HSS carbide long drills or brazed gun drills, can now be achieved easily with the existing gundrills

Assembly Instructions

Measure the DTD drill diameter between the measuring guide pad and the insert cutting edge. If a pre setter is not available, use a micrometer or caliper. For a precise drill diameter measurement, it is recommended to test-drill a hole and measure the hole diameter.

Select the shim combinations according to the chart on Page 4 to obtain the required hole diameter. Take into consideration that the actual diameter of the drilled hole tends to be slightly larger (usually +20 μm to +30 μm) than the drill’s nominal diameter — i.e. add 20 μm-30 μm to the measured drill diameter in Step 1 above before the final drill diameter.

Remove the guide pads.

Install the adjusting shims underneath the guide pads, respectively. Put the guide pads back on the tool.

Measure the drill diameter again to confirm that the required diameter is obtained on the DTD.

Drill a hole to confirm that the required hole diameter is achieved.

Shim thickness ID:
“1” indicates the shim is 0.01 mm thick
“2 for 0.02, “3” for 0.03 mm...

Item # Description Width W (mm) Length L (mm) Thickness H (mm) Applicable Guide Pad Size
6783757 SHIMSET-GP04 4 15.9 0.01-0.05 GP04
6783010 SHIMSET-GP05 5 18 0.01-0.05 GP05
6783011 SHIMSET-GP06 6 20 0.01-0.05 GP06

• A shim set contains 5 shims in thicknesses of 0.01 mm, 0.02 mm, 0.03mm, 0.04mm and 0.05mm respectively.
• Adjusting shims are sold by set only, and are not to be sold separately

Shim Combinations for Various Diameters
Diameter Adjustmemts (mm) Shim (s) for Measuring Guide Pad Shim (s) for Supporting Guide Pad Number of Shim Sets Needed
+0.01 0.01 - 1
+0.02 0.02 0.01 1
+0.03 0.03 0.01+0.02 1
+0.04 0.04 0.02+0.03 1
+0.05 0.05 0.02+0.03 1
+0.06 0.01+0.05 0.02+0.04 1
+0.07 0.02+0.05 0.03+0.04 1
+0.08 0.03+0.05 0.04+0.04 2
+0.09 0.04+0.05 0.04+0.05 2
+0.10 0.05+0.05 0.04+0.04+0.01 2

The NPA18-2019's pdf file: View (PDF) or Download (ZIP)