How to Fasten a Lag Shield

What You'll Need
Hammer drill
Masonry drill bit
Lag shield anchor
Machine threaded bolt
Safety glass and ear protection
Anchor setting tool
Shop vacuum
Round wire brush
Masking tape

A lag shield anchor is a female anchor that is designed to be used in concrete, brick or block materials to securely attach brackets or fixtures securely. A lag shield anchor is very strong and can support heavy items or provide a large amount of holding strength to secure items to a wall or slab. Installing a lag shield anchor is an easy DIY job that you can finish in about 15 minutes or less. This simple how-to guide will show you everything you need to know.

Step 1 - Set Depth of Hammer Drill

Use the depth gauge on your hammer drill to set the depth of the hole to the appropriate level. If your hammer drill does not have a depth gauge or adjustment, you can wrap a piece of masking tape around the drill bit at the point where you'll need to stop drilling. The bottom of the masking tape should represent the point where the top of the drill hole will be located.

Step 2 - Insert the Right Masonry Bit

When installing a lag shield anchor, it is important to choose the correct sized masonry drill bit. Generally speaking, you should choose a bit that is the exact same size as the lag shield anchor you will be installing. However, if the size is off 1/16 inch or so, it is probably not that big a deal as the lag shield will expand and fill the hole.

Step 3 - Drill the Hole

Make sure that your hammer drill is set to hammer mode, and that you are wearing your protective equipment. Then, hold the hammer drill straight up and down and drill until you reach the base of the drill bit or the bottom of the masking tape.

Step 4 - Clean Out the Drill Hole

Take a round wire brush and a shop vacuum and remove as much concrete debris and dust from the hole as you can. In order for the lag shield anchor to fit properly, it is important that the hole be as clean as possible.

Step 5 - Insert the Lag Shield Anchor

Place the lack shield anchor in the hole and tap it into place with the hammer. Make sure that the top of the lag shield anchor is flush with the material where it is being installed.

Step 6 - Affix Fixture and Secure with Threaded Bolt

Now, you can place your fixture or bracket over the lack shield anchor and insert the machine threaded bolt. Turn the threaded bolt clockwise and tighten with a wrench. As you tighten the threaded bolt, the lag shield anchor will expand inside the hole and create a very strong anchor for your fixture.

(Tip: Be careful not to apply too much torque when tighten the threaded bolt with the wrench as the anchor is easily damaged if expanded too much.)