All Category - Combined Core Drill and Counter Bore - Standard English Sizes

Standard English Sizes



This advanced cutting tool design combines into one operation, instead of two, the preparation of shallow cored holes for insertion of Hubbard (Welch Type) Expansion Plugs.

This cutting tool creates the following features in one operation:
  • Correct counter bore diameter for each specific plug diameter.
  •  Proper width of the bottom of the counter bore – equal to the thickness of the material.
  •  Correct angle between the cylindrical sides and the bottom of the counter bore – 96 degrees.
  •  Includes a chamfer at the top lip of the counter bore at a bore depth of approximately 1-1/2 material thickness. This functions as a lead in for plug insertion and is a nice feature considering the close fit of the bore and the expansion plug.
  • Stout, rigid cutting tool design eliminates chatter and insures the accuracy essential to machining square shouldered, leak-proof holes free of burrs and fillets.
  • Tooling appropriate for both low and high volume production work – T-15 tool steel and C-6 Carbide available.
  • Standard shank sizes that will work in any cutting tool holding system.
  • Cutting tools can be sent back to us for sharpening.
  • Maximizes sealing effectiveness of Hubbard (Welch Type) Expansion Plugs and Ground Plugs.


Item #
Plug Diameter
Plug Diameter Decimal
Plug Material Thickness
Price C-6 Carbide
Price T-15 Tool Steel
Note : click on item number to submit request for quote
CBore-HP-875-32 7/80.8750.032$309$210
CBore-HP-875-62 7/80.8750.062$309$210
CBore-HP-875-83 7/80.8750.083$309$210
CBore-HP-625-32 5/80.6250.032$288$196
CBore-HP-625-62 5/80.6250.062$288$196
CBore-HP-625-83 5/80.6250.083$288$196
CBore-HP-375-32 3/80.3750.032$250$170
CBore-HP-375-62 3/80.3750.062$250$170
CBore-HP-750-32 3/40.7500.032$301$205
CBore-HP-750-62 3/40.7500.062$301$205
CBore-HP-750-83 3/40.7500.083$301$205
CBore-HP-2125-32 2-1/82.1250.032$498$339
CBore-HP-2125-62 2-1/82.1250.062$498$339
CBore-HP-2125-83 2-1/82.1250.083$498$339
CBore-HP-2250-32 2-1/42.2500.032$513$349
CBore-HP-2250-62 2-1/42.2500.062$513$349
CBore-HP-2250-83 2-1/42.2500.083$513$349
CBore-HP-2500-32 2-1/22.5000.032$527$359
CBore-HP-2500-62 2-1/22.5000.062$527$359
CBore-HP-2500-83 2-1/22.5000.083$527$359
CBore-HP-2000-32 22.0000.032$483$329
CBore-HP-2000-62 22.0000.062$483$329
CBore-HP-2000-83 22.0000.083$483$329
CBore-HP-812-32 13/160.8130.032$301$205
CBore-HP-812-62 13/160.8130.062$301$205
CBore-HP-812-83 13/160.8130.083$301$205
CBore-HP-687-32 11/160.6880.032$294$200
CBore-HP-687-62 11/160.6880.062$294$200
CBore-HP-687-83 11/160.6880.083$294$200
CBore-HP-500-32 1/20.5000.032$268$183
CBore-HP-500-62 1/20.5000.062$268$183
CBore-HP-500-83 1/20.5000.083$268$183
CBore-HP-1562-32 1-9/161.5620.032$424$289
CBore-HP-1562-62 1-9/161.5620.062$424$289
CBore-HP-1562-83 1-9/161.5620.083$424$289
CBore-HP-1875-32 1-7/81.8750.032$469$319
CBore-HP-1875-62 1-7/81.8750.062$469$319
CBore-HP-1875-83 1-7/81.8750.083$469$319
CBore-HP-1437-32 1-7/161.4370.032$395$269
CBore-HP-1437-62 1-7/161.4370.062$395$269
CBore-HP-1437-83 1-7/161.4370.083$395$269
CBore-HP-1625-32 1-5/81.6250.032$439$299
CBore-HP-1625-62 1-5/81.6250.062$439$299
CBore-HP-1625-83 1-5/81.6250.083$439$299
CBore-HP-1375-32 1-3/81.3750.032$380$259
CBore-HP-1375-62 1-3/81.3750.062$380$259
CBore-HP-1375-83 1-3/81.3750.083$380$259
CBore-HP-1750-32 1-3/41.7500.032$454$309
CBore-HP-1750-62 1-3/41.7500.062$454$309
CBore-HP-1750-83 1-3/41.7500.083$454$309
CBore-HP-1187-32 1-3/161.1870.032$351$239
CBore-HP-1187-62 1-3/161.1870.062$351$239
CBore-HP-1187-83 1-3/161.1870.083$351$239
CBore-HP-1125-32 1-1/81.1250.032$336$229
CBore-HP-1125-62 1-1/81.1250.062$336$229
CBore-HP-1125-83 1-1/81.1250.083$336$229
CBore-HP-1250-32 1-1/41.2500.032$366$249
CBore-HP-1250-62 1-1/41.2500.062$366$249
CBore-HP-1250-83 1-1/41.2500.083$366$249
CBore-HP-1500-32 1-1/21.5000.032$410$279
CBore-HP-1500-62 1-1/21.5000.062$410$279
CBore-HP-1500-83 1-1/21.5000.083$410$279
CBore-HP-1000-32 11.0000.032$322$219
CBore-HP-1000-62 11.0000.062$322$219
CBore-HP-1000-83 11.0000.083$322$219
Total: 65