How to Size Machine Screws

Getting the right size machine screw for your project can be a frustrating experience. Not only do you need to know the diameter and length of the screw, you also need to know the thread pitch, or number of threads per inch. Screws of the same diameter with a different thread pitch are not interchangeable, and may damage the tapped threads in a nut or hole if you try to force it to fit. Fortunately, there is a simple method to determine which machine screw you need for your project.

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