How to Fix a Loose Lag Bolt

Time, weather, movement and gravity can all work together to loosen a lag bolt. It's easy to fix a loose lag bolt; it can be as easy as adding another component to the fastening nut. If the bolt's movement has enlarged the hole in which the bolt is installed, it can still be fixed using one of these options. Does this Spark an idea?

Instructions

1

Remove the nut, add a locking washer and replace the nut. A locking washer is a metal washer that looks like a doughnut with a tiny slice removed. The cut ends are then bent slightly away from each other. When the nut is tightened over the locking washer, these features grab it and hold firmly onto the bolt. Locking washers are useful for lag bolts used in situations where there is independent and unpredictable movement, such as fastening the legs to a kitchen table.

2

Remove the lag bolt and replace it with one that is only slightly larger. Go up the smallest bolt size possible. For example, if the existing bolt is 3/8 inch, try inserting a 7/16-inch bolt, which is 1/16 of an inch larger than the existing bolt. If the next bolt size is still too small, continue trying increasingly larger bolts, going up by the smallest bolt size or measurement possible.

3

Fill in the lag bolt's hole and drill a new one. This option only works if the object being secured can either be shifted slightly, or if it can have fastening holes drilled in a new location. Use aerosol foam insulation, silicon caulk or even Bondo to fill the old hole, depending on the material in which the hole is drilled. Drill the new hole at least inch away from the previous hole, insert the lag bolt and secure it with a lag nut.