This figure shows the types of screws used most often. The round head slotted screw and the round-head Phillips are the most popular. The screws shown in figure 5 are fabricated from standard screw wire stock. Sizes of standard screw wire are also shown in Figure B.

Screws are identified by a two-number code. Examples are 6-32 and 8-40. The first number refers to the size of the standard screw wire used for making the screw. The second number tells the number of threads per inch. There’s only one nut or threaded hole that will accept a screw with a two-number identification code. For example, a 6-40 screw will almost fit a nut made for a 6-32 screw. Almost isn’t good enough. Someone with an electric screwdriver may turn the screw with enough power to drive the screw partway into the nut before it wedges.

	Created by That Yeti Dog Person over 3 years ago

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