Plastic anchors are used to support light loads on drywall without fastening to a wall stud. Simple anchors just push into a guide hole, gripping the gypsum board and protecting it from the threads of the screw. Molly bolts and toggle bolts expand inside the wall. Molly bolts burst open and flare out when you insert a screw. Toggle bolts have spring-loaded metal wings that flare out. Some anchors also have spiraling flanges around the shaft that grip into the drywall inside the guide hole.
Step 1 – Select Appropriate Anchor and Fasteners for Weight
Determine whether the object you are trying to hang can be supported by a drywall anchor. Check the manufacturer’s specifications on the package of the anchor. These instructions should also indicate the diameter of the guide hole and the diameter of compatible screws. Tap-in anchors are rated for low weights; screw-in expanding anchors can hold slightly larger weights. However, you should only hang decorative objects such as picture frames or mirrors with drywall anchors. For heavy loads such as pot racks, you will need to attach to the wall studs. You can hang small shelving units with anchors but they will not be able to support volumes of encyclopedias. Overloading the anchors will cause them to tear out of the wall, leaving a gaping hole to patch and paint.
Step 2 – Measure and Mark Hangers
Measure out the locations of the guide holes using a tape measure and a level. You don’t necessarily have to use a tape measure, however. For objects such as calendars, which have holes, hold the calendar up against the wall with the level and draw a circle in the hole through a pencil. For objects with hanger brackets, such as mirrors, coat the back of the brackets with toothpaste. Now hang the mirror where you want it on the wall and level it out. Push it firmly against the wall so toothpaste will stick. Mark the stains with a pencil and drill them out. Take care when measuring so you don’t have to drill a second hole next to a mistake. This weakens the wall and reduces the weight the anchor can support.
Step 3 – Drill Guide Holes
Drill the guide hole according to the specifications on the package. You will usually drill a hole slightly smaller than tap-in anchors and slightly larger than expanding screw-in anchors. Push the anchor into the hole with your thumb; tap it into place gently with a mallet if necessary. Drive the anchor until it is flush with the wallboard. Pushing it any further is ineffective.
Step 4 – Drill Screw
Drive the screw into the anchor with a drill or screwdriver. With some expanding anchors, you may have to hold the anchor with pliers or a second screwdriver while you turn the screw. For hanging picture frames and mirrors, leave the head and a small length of screw sticking out to support the mounting brackets.