Bolt Circle Diameter Calculator

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

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.

HiTorque 4190 Deluxe Mini Mill

Factory installed 3-axis DRO and interlocked spindle lock
Most powerful mill in its class with the most low speed torque
No gears in spindle drive
Largest table and X-Y travel in its class
R8 spindle and drill chuck

$1,999.00

More products like this

SIEG C3 7x14 Mini Lathe

Full featured miniature lathe at an incredible price
Includes 3" 3-jaw chuck, 2 sets of jaws, and chuck key
Variable speed with two speed ranges for low speed torque
Digital spindle speed readout
Cam-lock tailstock

$999.00

More products like this

Dial Indicator, Test Indicator, Magnetic Base & Point Set

0-1" dial indicator with 0.001" resolution
0-15-0 dial test indicator with 0.0005" resolution
Magnetic base indicator holder with fine adjustment
22 piece indicator point set
All in a plastic case

$59.95

More products like this