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Quick Change Tool Post Set, 0XA, Horizontal Cut-Off, Mini Lathe
 
 
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Measuring Tools
Test Indicator Holder, Professional Grade
Test Indicator Holder, Professional Grade
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Machinist's Calculator

Our mobile app; read this with your phone.
lmscnc.com/calc

 
Online Metals  

 

  

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
Transfer Punch Set 3/32" to 1/2" $9.95

More information
Transfer Punch Set 3/32" to 1/2"
Tooling Package, Mini Lathe, 0XA QCTP
  • QCTP Set easily mounts to 7x10, 7x12, 7x14, 7x16 lathes
  • 3/8" indexable TCMT inserts, P1N cut-off blade
  • 9-piece carbide boring bar set - 3/8" shank
  • 1/2" drill chuck, 2MT short to 33JT drill chuck arbor
  • 4 center drills (sizes 1-4)

$225.95

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PORTaMIST Spray Mist Unit 18"
  • Kool Mist model 60M18, mist spray system
  • 18" Lock-Line® spray positioner
  • Heavy-duty magnetic base
  • Adjustable coolant nozzle
  • 4' coolant and air hoses

$153.00

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The Milling Machine for Home Machinists
  • Provides detailed knowledge in choosing, installing and operating a milling machine for your shop
  • By Harold Hall
  • 119 pages, softcover, 5½" x 8½"
  • ISBN 978-1-56523-769-8
  • Copyright 2013

$14.99

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