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Collet Holder, R8 Rotating
 
 
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QCTP Sets
Quick Change Tool Post Set, 0XA, Horizontal Cut-Off, Mini Lathe
Quick Change Tool Post Set, 0XA, Horizontal Cut-Off, Mini Lathe
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Bolt Circle Diameter Calculator

Calculator Menu

Enter values below to calculate the diameter of a bolt circle.

Number of Holes N
Center Distance Between Adjacent Holes  in  mm
 

Tip:

To measure the center distance between two holes of equal diameter with an electronic caliper.

1. Use the inside jaws to measure the diameter of one of the holes. Before you remove the caliper from the hole, press the button to zero the caliper while it is set to the diameter of the hole.

2. Still using the inside jaws, measure the distance between the far surfaces of the two holes. The caliper reading is the distance between centers of the two holes.

 
SPECIAL OF THE WEEK
Lathe Chuck, 4-Jaw 3", Independent $84.95

More information
Lathe Chuck, 4-Jaw 3", Independent
The Metalworker's Workshop for Home Machinists
  • Provides a solid base for everything metal working
  • By Harold Hall
  • 127 pages, softcover, 5½" x 8½"
  • ISBN 978-1-56523-697-4
  • Copyright 2013

$14.99

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Magnetic  Indicator Holder - CLOSEOUT
  • Magna-type magnetic indicator holder
  • Designed to be used with small test indicators and dial indicators
  • Fine precision adjustment
  • 1/4" stainless steel 6" long holding rod
  • Permanent magnet has a 50 lb holding force

$18.95

Regularly $49.95

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Tool & Cutter Sharpening for Home Machinists
  • Tips and instructions for tool sharpening from an expert
  • By Harold Hall
  • 136 pages, softcover, 5½" x 8½"
  • ISBN 978-1-56523-912-8
  • Copyright 2017

$12.99

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