Importance of Contact Pattern in Assembly of Bevel vs Cylindrical Gears

The article "Importance of Contact Pattern in Assembly of Bevel vs Cylindrical Gears" appeared in the August 2014 issue of Gear Technology.

Summary
Why is there so much emphasis on the tooth contact pattern for bevel gears in the assembled condition and not so for cylindrical gears, etc?

Keywords
contact pattern, bevel gears, cylindrical gears, assembly, basics

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