How To Measure Sheet Metal Screws

When measuring the gauge of self drilling metal screws with a drill point the gauge should be measured fom the drill point or inbetween the thread as per this image from hobson.

How to measure sheet metal screws.

For softwoods choose drill bits. For example 1 inch 5 thread gaps 200 inch. Use a ruler or measuring tape to measure from here to the tip of the screw. The size dimension pertains to diameter of screws bolts pins and inner diameter of nuts and washers.

Measure in inches from the tip to where the screw head rests to get the length. If you have some stray screws and bolts a k a. Other size measurements such as screw bolts pin length the outer diameters of nuts washers etc appear on the search result itself. To measure the diameter of screws and bolts you measure the distance from the outer thread on one side to the outer thread on the other side.

Understanding standard size dimensions. How to calculate the hole size for screws step 1. You can also measure from the bottom cavity of the threads from one side to the other to find the minor diameter. Pan head truss head and hex head screws are measured from under the head.

For other screws including self taping wood and self drilling timber screws the gauge is taken as a measure of the major diameter of the screw as per below. Wherever the screw head would rest when it is fully embedded in something is where you start the measurement. Set that drill bit aside to drill the pilot hole in hardwood or sheet metal. This is called the major diameter and will usually be the proper size of the bolt.

Eye bolts and eye lags. If there are five threads gaps in a 1 inch length the thread pitch is 200 inch. Countersunk screws flat or oval head are measured by overall length. There is 200 inch between each thread and the screw has a tpi of 5.

You may search for your product based on diameter by selecting a measurement on the size dropdown. Divide the count of thread gaps into the length.