7. Avoid separate fasteners. The use of fasteners increases the cost of manufacturing a part due to the
handling and feeding operations that have to be performed. Besides the high cost of the equipment
required for them, these operations are not 100% successful, so they contribute to reducing the overall
manufacturing efficiency. In general, fasteners should be avoided and replaced, for example, by using tabs
or snap fits. If fasteners have to be used, then some guides should be followed for selecting them.
Minimize the number, size, and variation used; also, utilize standard components whenever possible.
Avoid screws that are too long, or too short, separate washers, tapped holes, and round heads and flatheads
(not good for vacuum pickup). Self-tapping and chamfered screws are preferred because they improve
placement success. Screws with vertical side heads should be selected vacuum pickup.