When it comes to figuring out the thread count on a screw you just made or a hole that you just tapped, there are ways to do that. One of them is to use a thread gauge. With the appropriate thread gauge, you can figure out the count and what kind of hardware you need to work with that particular item. Before you use a thread gauge, you need to understand the basic terms when it comes to screws.
Thread
The thread is the ridge that runs around the screw. That ridge generally runs along a diagonal in reference to the post of the screw. That's what gives the screw the mechanical force it needs in order to make a connection.
Pitch
The pitch of the screw thread is one of the various measurements that is used to measure the screw's thread. It measures the distance between two points on the thread. The measurement is made by measuring one point on the crest of the thread to the exact same point on the next crest of the thread. If the thread that you are trying to measure has more than one start, meaning it has more than one thread, then each of those threads gets measured separately. You would measure the pitch of one thread by just ignoring the other thread. Then you can switch to measure the other thread.
Lead
The lead could seem like it is the same measurement as the pitch, since it also involves measuring from one crest to another. The lead is actually a measurement of distance. The lead is measured with one full rotation of the screw, from point A on one crest of the thread to the exact same point on the next crest. Instead of measuring the space in between the two points, the measurement is how far along the post of the screw it travels as it is being rotated. On a double tapped screw, the lead is also measured on each thread separately, but the measurement would be expressed by counting both of the rotations at the same time.
Thread gauges are good at giving you a reasonably accurate measurement of the thread on the screw. It can be a good way to make sure that you know what the screw's measurements are before you start working with that particular screw, or to double-check something so that you are going to be able to do what you need.
You can contact a hardware company such as WESTport for more information about thread screws.
