8

I put up some shelves at the weekend, and had a tough time driving the screws into the wall plugs (drilled a 6 mm hole in the masonry, then used brown wall plugs and #8 screws). I got there in the end, but not without lots of effort and blisters on my screwdriver hand.

Is there a way of getting more torque for jobs like this? I have an electric screwdriver, but it wouldn’t get any purchase on the screws. Seems like some sort of ratchet arm would be perfect, as long as I could still put enough pressure on it in the direction of the screw to keep the bit engaged. I’ve also seen T-handle screwdrivers, and drivers with a hex addition to the shaft so you can get extra torque with a spanner. What’s best?

(It might be that I was using wall plugs that were too big, but the screws went in eventually, and I’m pleased with how secure they seem.)

  • 1
    first step is to make sure the hole, plug and screw are all compatible. – ratchet freak Jan 23 '17 at 10:59
  • 1
    A picture is worth a thousand words. Any chance to get a glimpse at your project, tools, and hardware? – MonkeyZeus Jan 23 '17 at 14:41
  • The answers are good, but just to throw this out there: Lubricating the screw with detergent can be used in a jam (no pun intended). – Jim W Jan 23 '17 at 21:51
28

drilled a 6 mm hole in the masonry, then used brown wall plugs and #8 screws

Your hole was too small and the screw was the wrong size or type. A #8 screw has a 4mm diameter.

Brown wall plugs fit into a hole made by a 7mm drill bit and are for screw sizes 10 - 14

Plug            Hole            Screw
Colour          Size            Size
------          ----            -----
Yellow          5mm             4 - 8
Red             6mm             6 - 10
Brown           7mm             10 - 14
Blue           10mm             14 - 18

Note: the above screw sizes are traditional size or screw-gauge. If you drill metric holes, you might be buying metric screws, where the size is the major diameter of the threaded part in mm.

If you can't drive the screw using a normal hand-held screwdriver, then something is wrong and you are at risk of shearing the screw or damaging the head. Using more force is not the right answer.

  • 2
    This is interesting. Is there some color standard in the UK that all wall plug manufacturers adhere to? – JPhi1618 Jan 23 '17 at 15:04
  • 1
    @JPhi1618: I expect it's just that a few major brands have followed a convention established by the market leader. – RedGrittyBrick Jan 23 '17 at 15:19
  • 1
    How is a 6mm hole too small if 4mm is the right size? – JDługosz Jan 24 '17 at 2:36
  • 2
    @JDługosz the 6mm hole is too small for a brown plug. The hole is already too full of squashed plug, so there is no room for the screw. – alephzero Jan 24 '17 at 3:47
  • 1
    Thanks to all for the excellent comments. To address the mystery of how 7mm plugs went into 6mm holes: although the drill bit was 6mm, I suppose that in the process of using a hammer drill to go into the masonry, I ended up with holes that were slightly bigger. The plugs went in snugly (albeit with a bit of encouragement from a hammer in some cases). – microlambert Jan 24 '17 at 14:19
5

First of all, make sure you are using the correct bit on your electric screwdriver. If the screws have a cross-shaped head, check whether you need a Philips or a Pozidriv bit for it. Pozidriv has an additional "X" shape on the screw, and using the wrong kind of bit will cause slippage. There are many online guides how to identify the proper bit, such as this one.

However, the ultimate solution is to buy screws with either a Torx (star), Allen (hexagon) or Robertson (square) head, and the corresponding bit for your electric screwdriver. These screw heads are designed so that they won't slip easily, and you don't need to press the screw driver to keep contact.

  • I've read somewhere that Torx design has the best shape for torque transfer. It is stable (unlike flat screw), doesn't tend to "skip" like Philips and has better angle of attack than Allen and Robertson. – Crowley Jan 23 '17 at 16:23
  • 1
    As well as the correct type make sure you use the correct size. . – Peter Green Jan 23 '17 at 18:11
  • Thanks for the alert about Pozidriv. Gotta admit that I didn't have an operational understanding of the difference, and this was the cause of some considerable puzzlement and grief. Another type of driver is a combination Phillips/square drive. Boxes of Deck Mate all purpose exterior screws contain these labeled "PSD 2 - 2". I didn't understand why what I thought was just a Phillips drives these screws so well. – Jim Stewart Jan 23 '17 at 20:51
  • @Crowley If only I could find larger Torx bits and screws I would use them for everything....That said, the only thing I currently have a use for Torx drivers is for electronics and computer repair. But I do have to say that the screws tend to stay on the bits after you remove them, even when the bits are not magnetic. – NZKshatriya Jan 24 '17 at 3:14
  • @Crowley Torx isn't very good at torque transfer, because all edges are slanted. No shape without surfaces perpendicular to the torque can excel at torque. Bristol, LINE and Polydrive are pretty much the only ones that do just that. Their rarity only proves that torque transfer isn't as important as low cost of production when it comes to screw heads. On shafts, it's the other way around, hence spline is dominant. – Agent_L Jan 24 '17 at 11:15
4

You shouldn't be using a drill.

My own what should I use chart:

  1. Drilling into something that is delicate or could damage/scuff = Drill

Examples - Drywall, cabinets, furniture, toys

  1. Drilling into masonry directly = Hammer Drill

Examples - Screwing directly into concrete or brick

  1. Drilling into something tough that needs a lot of torque = Impact Driver

Examples - Hardiboard, brick, framing wood, sheet metal

You are simply using the wrong tool for the job. Let me tell you the Impact Driver is the bee's knees for any tough job. It wins out by far and require much less pressure by the user.

  • 3
    Having only recently bought an impact driver, after using a drill to drive screws for the past few years, I can't help but agree that they're the bee's knees. – AndyT Jan 23 '17 at 15:45
3

One solution that is in direct answer to the question is to get a different type of screw driver. This one listed on Amazon provides a large grip plus a reversible ratchet action to make screw driving easier.

enter image description here

2

You need to understand that using a drill as a screwdriver always runs the risk of slippage. The only ways to get better driving are

  1. Drill a pilot hole (which you did)
  2. Get a better driver. Drills are designed to drill primarily. They spin the shaft as fast as they can. This isn't ideal for driving screws. Impact drivers help some, but I've also noticed most cordless drills, nowadays, have a speed setting to go between driving and screwing. Even an electric screwdriver can help in this area, because they focus on torque.
  3. Apply better pressure. If you've got a hard screw to drive, put as much pressure behind the screw. If it's not going in with one hand, use two. Lean in behind it. I recently used my cordless to drive 3" screws into a door I was installing. I pressed hard against the other side of the jamb and squeezed the trigger gently and it went pretty smoothly without a pilot hole.
  4. Change bits. Get some square drive screws. They're harder to find locally, but they drill so much better. Star drive is another option, but they're not common for interior applications (most decks today are screwed together so star drive for pressure treated is easy to find)
  • Agree with the suggestion of star drive, which is just the generic name for Torx. – NZKshatriya Jan 24 '17 at 3:16
1

When seeking more toque (and bearing in mind the potential to apply "more torque than the screw can take, thus shearing it") a simple ratchet wrench, perhaps with an extension, and an insert bit in a standard size (typically 1/4" here, but there are others) is my default approach. Easy to both push in and turn, and also relatively easy NOT to overdo it and strip/chew parts as is too often the case when overpowering with an electric driver.

For very serious things I like a hand impact driver (actually a combination of hand pre-load and a manual hammer) but there's few times indeed I'd use that for tightening, rather than loosening.

0

When I need more torque with a screwdriver I use second one (philips or pozidriv) pushed through a hole in the handle.

We also used to have screwdrivers made from hexagonal beam instead of round one. And wrench could be used to increase the torque.

Another possibility is to use mechanics tool set. Use appropriate bit, screwdriver and ratchet attached to the screwdriver. With larger sets you have more options to set your torque enhancer up.

0

Get an impact driver and you can drive a four-inch screw into just about any hardwood without a pilot hole. Stay away from anything done by hand or with electricity. "electric screwdriver?"

My choice is the cordless lithium-ion battery-powered impact driver by Makita: makita impact driver

This is the best "if-you-could-only-have-one" screwing device ever manufactured.

Through a combination of bit rotation and concussive impacts to the screw, an impact driver easily drives every type of screw or lag bolt into very dense materials with ease. Impact drivers usually deliver 2-3 times more torque than a cordless drill and in a recent Popular Mechanics test, an 18V cordless impact driver drove 138 3-inch lag bolts into solid wood on a single charge.

All that said, if you can't get your hands on an impact driver, a properly-sized pilot hole is the key for all scenarios. Including situations where you have the impact driver. You should never have to use such incredible force that it can't be done easily with whatever device you are using - even if by hand with a regular screwdriver.

  • There's too little data to back a particular brand. You don't even cite positive personal experience with the Makita impact driver. – DepressedDaniel Jan 24 '17 at 1:49
0

So, it turns out I was using the Phillips bits with Pozidriv screws - embarrassing! I have rectified that with some Dewalt Pozidriv bits.

But what also made a huge difference on my most recent job was the introduction of a ratchet handle instead of a screwdriver. All the screws went in without slipping or deforming, and my hands were saved from blisters. I've persisted with the brown plugs in 6 mm holes, and I have to say they feel really secure.

Thanks all for the tips.

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