Screw Sizes and Types
When it comes to choosing the right screws for your projects, getting the size right is one of the most important factors. Using the wrong screw sizes can cause the screw to bend, break or come loose over time.
Screw sizes are usually described by a number that indicates both the diameter and the number of threads per inch of the screw. The number is known as the gauge; for example, a #8 screw has a head diameter of one inch and a shank diameter of half an inch. The diameters are reduced as the gauge gets smaller, so a #2 screw has a head diameter of 1/3 an inch and a shank diameter of 1/8 an inch.
The type of material you are working with will also affect the type of screw you need. For example, wood screws have a tapered thread that provides better hold in the wood than sheet metal screws with larger spaces between their threads. Wood screws also have a helix angle that enables the screw to cut its way through the wood, rather than just pushing into it.
It’s a good idea to buy different types of screws in a variety of lengths to ensure that you have the right ones on hand for each job. That will save you from having to make a trip to the hardware store for more when you need them and ensure that you always have the correct screws available. pilot hole for 5/16 lag screw