A lag bolt is a kind of screw that’s used to fasten wood. It’s commonly used in home renovation projects, but it’s also a staple of construction and the trades. In this article, we’ll take a closer look at the basic structure of a lag bolt and how to properly use one.
Lag bolts are heavy-duty screws, which means they’re designed to connect lumber and other materials that will be bearing intense loads. They’re different from standard wood, self-drilling or sheet metal screws because they generate massive clamping forces when tightened, which helps prevent the mechanical connection from loosening over time. Lag bolts require that you predrill a hole into the wood before screwing them in.
The basic design of a lag bolt is comprised of three parts: the head, shank and threading. The head is typically hexagonal or square so it can be driven into the material by a wrench or ratchet. The shank is tapered to make it easier to drive into the material, while the threads create a type of friction joint that holds the materials together securely.
Depending on the application, you may choose a lag bolt with an external or internal hex head. An internal hex head provides greater strength and grip, while an external hex head is better for fastening with tools that have a hex socket. You should lubricate your hex bolts with either beeswax or bar soap before and after installation to ensure they’re as smooth and strong as possible.
When choosing a lag bolt for your project, it’s important to choose the right size. You want to use a screw that’s slightly larger than the size of the materials you’re attaching. This will ensure that the screw can easily penetrates and bonds with the material without ripping out of the holes.
After drilling a hole into the wood, you should insert the lag bolt and screw it in. Be sure to use a washer under the head of the screw to distribute the clamping force over a wider area and avoid compression of the materials being joined. Using a washer also makes it easier to remove the bolt when needed for maintenance or repairs.
It’s best to use a lag bolt that’s made of a material that’s resistant to corrosion. Zinc is the most common, but a variety of hot-dipped galvanized or stainless steel options are available as well. You can also find lag bolts that are coated with epoxy or other protective coatings.
If you’re not familiar with lag bolts, they’re much larger and more specialized than other types of screws or bolts. Lag bolts are a great choice for joining wood because they can support high loads and provide long-lasting structural connections. But if you’re not careful when installing them, they can cause damage or weaken the structure of your building. So be sure to read this article and follow the tips we’ve provided to get the most out of your lag bolts. lag bolts for wood