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A hex bolt used in carpentry is identified by its hexagonal head and (shown here) fully threaded.

Hex Bolt

A hex bolt used in carpentry is identified by its hexagonal head and (shown here) fully threaded.

The hex head bolt and nut illustrated and head, diameter, pitch, and lenght identified.

Hex Head Bolt

The hex head bolt and nut illustrated and head, diameter, pitch, and lenght identified.

A cylindrical helix is a curve generated by a point moving uniformly around a cylinder and uniformly lengthwise of the cylinder at the some time. The hypotenuse of a right triangle will form one turn of a helix if it is wrapped around a cylinder. The base of the triangle is equal to the circumference of the cylinder and the altitude is the pitch of the helix.

Helix

A cylindrical helix is a curve generated by a point moving uniformly around a cylinder and uniformly…