Concrete/ cement screws for dry wall?

Question

So my question is if my only option was to use anchor for dry wall/ plaster with screws for concrete/ cement would it still work as stronger than drywall screw? Any ideas please thank you I think the only real problem I see is you might need a socket wrench instead of a regular screw driver any ideas please thank you

Answer 1

So, it's difficult to understand exactly what you're asking--are you are asking "What is stronger than a drywall screw for hanging heavy things like pictures or fire extinguisher brackets?"

Cement screws are NOT drywall anchors, they are specifically for cutting channels in cement. Drywall is much different than cement, and just putting a larger screw in, or a screw designed for cement, won't help you. Then again, drywall screws are NOT drywall anchors either. Drywall screws specifically have a larger thread pitch to minimize the damage to the gypsum between the paper sides of the drywall, to preserve the integrity of the drywall they're going through to mount that drywall to a wood stud or joist. If the threads were finer, they would remove more drywall as they penetrated to the stud and make the drywall around the screw structurally weaker. And using a larger screw just makes a larger hole in drywall, it does NOT increase the strength. You need to use a proper drywall anchor, and one rated for the weight you want to hang.

Small drywall anchors rely on friction to hold the screw in the drywall. A slightly smaller hole is drilled, the plastic anchor is tapped into place with a hammer, and a fine-pitch fastener is then screwed into the plastic anchor, expanding the end of the anchor the deeper it goes. This expansion creates friction that holds the anchor in place. Whenever you hanging something on a vertical surface, you create sheer force where the downward force is supported by the strength of the fastener + the ability of that fastener to remain in its medium. This requires that the anchor stay embedded in the material (drywall in this case), and that the diameter and material of the fastener are sufficient to resist the sheer force they are experiencing. If the sheer force exceeds the force of friction + compression of the anchor, the anchor pulls out of the wall. If the sheer force exceeds the rating of the fastener (assuming a fastener without manufacturer defects), the end of the fastener not in the anchor breaks off.

If you want to hang heavier items on drywall, you need to use anchors designed to spread the load over a larger surface area of the drywall, and your choices are typically either threaded plastic drywall anchors, which have much deeper threads than a screw, and rely on spreading the load over a larger area of drywall--the threads themselves sort of act like washers, whose purpose is (in part) to spread a force over a larger area. They make some very beefy ones that can support 50+ lbs, depending on 1) the thickness of the drywall, and 2) the structural integrity of that drywall. Drywall relies on its paper covering to provide resistance to fracturing; if you're trying to mount an anchor in a place that previously had other anchors filled with spackle or wallboard compound, the strength of the drywall in that area is already compromised, so a threaded plastic anchor of the same size is already going into weakened material. You would have to use an anchor larger than the previous damage to reach drywall that has intact paper and unfractured gypsum.

Another alternative is using wing-type drywall anchors. There are both plastic and metal ones, but the principle is the same. A hole quit a bit larger than the screw is drilled into the drywall, to accommodate a folded "wing". In its collapsed/folded state, the wing is pushed through the drywall; once it's through, the action of the fastener being screwed in (in the case of plastic anchors) or an internal spring in the wings (in metal anchors) forces the wing arms to expand, which again spreads the load over a larger surface area, allowing the anchor to withstand more sheer force from a larger weight. Plastic anchors typically have a washer-like head that the fastener screws into, so you drill the hole and lightly hammer them in place like a regular compression wall anchor, then screw the fastener which forces the wings to expand; they can work but are more prone failure if overloaded, as the plastic will deform and allow the wings to begin squeezing back out of the anchor hole, damaging the drywall along the way. Metal anchors typically require the screw be inserted into the wing first, then the wing is squeezed closed and pushed through the hole. Once through, the wings expand due to the spring, and pulling back on the fastener to pull the now-opened wing against the drywall is needed to provide enough friction hold the wing still, allowing you to screw the fastener in further. The wings of metal anchors are much larger than plastic ones, so require a much larger hole; however, they are less prone to failure from the plastic being stripped out and allowing the wing to collapse back through the hole at a later point. They usually can support much more weight as well, as their wings are much longer and thus spread the force over a much larger surface area. However, they don't work for leaving an end of the screw out to hang things on; they need to be tightened down against a metal surface to provide stability to wings in the rear and keep the fastener perpendicular to the drywall, so they're really only good for hanging a bracket or flat surface on drywall, such as a TV mount, shelving or cabinetry. In theory they'd work for a fire extinguisher mounting bracket, but they'd be overkill for that need.

And if what you're mounting is much heavier (think plasma TV wall mount), then as a commenter above states, large screws directly into studs is the only solution, is the least likely to fail for objects of any weight (provided a fastener with a sufficient sheer-force rating is used, and one with a course pitch), and causes the least damage to the drywall.