How Do You Measure Sheet Metal Screws

For flat and oval heads, length is measured from the top of the head to the tip of the thread; all other sheet metal screw head styles (hex, pan, round and truss) are measured from under the head to the screw’s tip.

Is a #8 or 10 screw bigger?

Machine screws are often found in sizes of: 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14—the larger the number, the larger the screw.

Does screw length include head?

Does Screw Length Include the Head? … The nominal length of a screw is usually, though not always, measured from below the head to the tip of the screw. If no head exists, such as on a grub screw or threaded bar, the screw would be measured from end-to-end.