How to Install Lag Bolts
Standard wood screws do not have the tensile strength to make a structural wood connection. Lag bolts, with large coarse threads and heavy shaft, are designed for this purpose. A lag bolt grabs with such force, that if you do not drill a pilot hole through the wood being joined, the head of the lag bolt is likely to break. To allow the lag bolt to thread into the wood and still allow for a strong structural wood connection, the pilot hole needs to be the diameter of the lag bolt shaft and no larger. Does this Spark an idea?
Other People Are Reading
Things You'll Need
- Lag bolt
- Drill bit set
- Reversible drill motor
- Safety glasses
- Socket set
- 3/8-inch ratchet
- Wood
Instructions
-
-
1
Place the lag bolt on a flat surface with the bolt's hex head facing away from you.
-
2
Select a drill bit from the drill bit set that is close in diameter to the shaft of the lag bolt and hold the drill bit over the lag bolt, with the drilling point aimed at the hex head of the lag bolt. The drill bit should cover the shaft completely, but not the lag bolts coarse threads.
-
-
3
Insert the proper drill bit into the chuck of the drill motor, secure the drill bit in the chuck of the drill motor and put on your safety glasses.
-
4
Align the tip of the drill bit where you need to install the lag bolt, hold the drill motor straight and drill the pilot hole through all the wood members that you are going to join with the lag bolt.
-
5
Match a socket from the socket set with the hex head of the lag bolt and attach the socket to the 3/8th-inch ratchet.
-
6
Hand thread the lag bolt into the pilot hole to hold it in place.
-
7
Place the socket that you affixed to the ratchet in Step 5 onto the hex head of the lag bolt.
-
8
Turn the lag bolt clockwise with the ratchet to thread the bolt into the wood. If the lag bolt binds in the hold, reverse the direction of the ratchet, turn the lag bolt 1/4 to 1/2 of a turn and then continue threading the lag bolt into the wood members.
-
9
Stop threading the lag bolt when the hex head rests tightly against the wood. Over tightening the lag bolt could result in the head of the bolt breaking and this will result in a non-structural wood connection even though the threads are locking the wood members together.
-
1
