Placing the Anchors
Be precise. You do not want to re-do this. One disadvantage of using anchors as opposed to screws is that you’re going to end up with a big enough hole in the wall that if you were close, but not close enough you won’t get a second chance.
Again, be precise.
If your anchor is self-tapping, you’re going to be in a good spot now. If not, you’ll need to take a look at the box and figure out how big of a hole to drill. Most quality brands will have some instructions here, otherwise, you may have to wing it.
If improvising on the drilled hole, start small, see if it fits, and then go up incrementally. You can always take a bit more off, but you can’t put it back and if the hole is too large you’re not going to be a happy camper at the end of the day.
It might seem obvious to most of us, but keep the drill perfectly horizontal as you go in. The goal is to drill a channel that’s absolutely perpendicular to the surface of the drywall itself. Any deviation over a degree or two is going to result in trouble in just a moment.
After this, you’ll find that you have a couple of different types of anchor to choose from and each has their own peculiarities.
Self-expanding anchors are the most straightforward. Get the appropriate sized hole, stick it in the hole. If it’s a bit tight, and it should be in most cases, tap it carefully in with a hammer or rubber mallet.
While some would advise against using a hammer here, we find that people have a tendency to just bash away with a rubber mallet since the damage to the wall will be minimal. This can damage the anchor. You’re not trying to drive a nail into a two by four here, if minimal tapping doesn’t get it in, widen the hole by the smallest increment possible and try again.
Self-screwing anchors make the whole thing extremely simple. Simply drill a tiny hole in the correct location, then place a machine screw that’s sized appropriately through the center. You don’t actually need to drill the hole, but we recommend it since it’ll give you the perfect guide hole.
If you’re not looking for much penetration, you can even break off the expanding tip and use a slightly wider pre-drilled hole to get things going. Screw it in, screw the screw in, and you’re done.
Molly bolts are a combination of self-expanding screws with the strength of metal. They’re a rather cool little piece of engineering and strongly recommended if you can afford to lay down the money for them.
Drill a hole the size of the molly and insert the anchor. Tap it with a hammer if necessary. Many manufacturers claim that you can just drive them in with a hammer, but this has two major disadvantages: the first is that, well, it often doesn’t work properly. The second is that it can be less precise.
After the anchor is inserted, turn the screw in the anchor clockwise a couple of times, just enough that the molly pulls tight against the wall. Don’t pull too much or you’ll degrade the drywall and be left with a loose molly bolt in the wall, which definitely isn’t what you’re going for.
Then you can pack the screw off and use it as an anchor.