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Sensitive Drill Feed and 1/8" (3 mm) Keyless Drill Chuck
 
 
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Indicators
Point Set, Dial Indicator
Point Set, Dial Indicator
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Machinist's Calculator

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lmscnc.com/calc

 
Onliine 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
Chuck Stop, 3-Jaw, 3 Piece Set $109.95

More information
Chuck Stop, 3-Jaw, 3 Piece Set
Edge and Center Finder, 3/8" Shank Laser
  • 3/8" shank fits collets and end mill holders
  • 3.375" overall length
  • Uses common SR44 batteries (included)
  • Accuracy to 0.001"
  • Includes polarizing attachment to adjust dot size

$114.50

Regularly $124.50

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Tooling Plate, 6 x 12"
  • Made from aluminum plate 3/4" thick
  • Plate is 6" x 12"
  • 220 Holes tapped 1/4"-20, 72 holes for locating pins
  • Includes clamping kit
  • Designed for small work pieces

$139.95

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Spindle Lock, Interlocked, HiTorque Mini Mill
  • Makes tool changes easier, faster, and safer
  • When engaged, the plunger automatically drops into the locking hole as the spindle is rotated
  • An electro-magnetic interlock disables power to the motor when the spring plunger is engaged
  • Frees both hands for changing tools
  • Loosen and tighten keyless chucks with one hand

$119.00

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