Which is the correct formula to calculate the center distance between gears? I am designing a couple of spur gears in Autodesk Inventor and the application says that the center distance between them is 23.107 mm, but when I place them so far apart they seem to overlap.(adsbygoogle = window.adsbygoogle || []).push({});

The gears have the following dimensions:

Gear #1:

Pitch diameter = 6 mm

Number of teeth = 12

Gear #2:

Pitch diameter = 40 mm

Number of teeth = 80

The module consequently is 0.5 mm

Logic says that the center distance must be distance between the centers of the gears placed close enough so their pitch diameters are tangent - so the sum of the radii would be the center distance, but a distance of 23 mm seems way too small.

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# Center distance between gears

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