Lag screws commonly referred to as lag bolts are some of the toughest fasteners and are extremely sturdy. These fasteners are generally used to connect heavy lumber or other heavy materials which are intense load bearing. They are really very huge in size in comparison to the normal screws and are characterized typically by a hexagonal head. In general lag bolts are at least an inch in length and come in a minimum thickness of ¼ of an inch.
Unique characteristics of lag bolts
Lag bolts are typically big sized and are available only with a head that is hexagonal in shape on the external side.
Lag screws come with sharp lead thread points and available in various materials such as steel/zinc, stainless steel, and steel/hot dip galvanized.
Lag bolts require a nut for enabling extra strength and security for holding things that are fastened together.
Lag bolts are instrumental for supporting intense load applications much heavier than what the average screws such as wood screws or sheet metal screws can support.
Lag bolts need two predrilled holes where one is for the threads and the larger hole to serve as a clearance hole for the shaft.
How to install lag bolts
For installing a lag bolt first of all you have to ensure that all of the materials involved in the application are properly aligned.
Once you are sure that they are aligned as required you must ensure that they are in place; for this you have to use clamps to hold them in place.
After everything is secured you have to drill a pilot hole with a bit that is a little smaller in diameter when compared to the diameter of the lag screw that you are going to use.
Ensure that you drill the hole all the way through the area where the screw is finally going to be.
You can complete the tightening of the lag screw using a right driver bit and a power drill.
Lag bolts and their hex heads
Like already stated above, lag bolts are available only with hex heads whereas the other more common wood and sheet metal screws are made available in different head types.
Since the only option in Lag Bolts is with hex heads the installation of this screw requires a nut driver and a ratchet and for tightening the screw a right driver bit and a power drill is needed.
The hex head lag bolt is designed in this manner since these fasteners are mainly used for holding in those applications which require a lot of torque.
Difference between lag bolts and other screws
Lag bolts are much bigger in size and come only with external hex heads.
Others such as wood screws are used for connection application with wood material only.
Wood screws have coarse threading though it is not there on the entire length of the screw.
Normal wood screws thread while they enter the wood but lag screws need a hole to be drilled first and require a nut for additional strength.
Lag screws can support a lot more heavier load than the normal wood or sheet metal screws.
Lag screws are labor intensive though are readily available.
Lag screws cost a third of the price of structural screws.
Finally if you're looking for using a lag bolt on industrial projects or a job where you need that extra bit of secure fastening, we'd suggest choosing heavy duty lag bolts.
Don't be afraid to seek advice if you're unsure how to how to install a lag bolt yourself, after all it's better to be safe rather than sorry.