DIY techniques: Removing old nail and screw fixings
How you go about removing old screws and/or nails depends on how the fixing was originally made. It also depends on whether you need to do the job with care, or whether you can take a 'wrecking' approach. Here are some of the options.
Removing old screws
In most cases, there are three things that make old screws hard to remove.
Their heads are often over-painted, making it difficult to engage a screwdriver tip positively.
Plain steel screws tend to corrode with time, so their screw threads grip the wood tightly and are very difficult to free.
The screw head may have been damaged as the screw was driven in, with the result that the screwdriver tip slips out of the slot or recess as you try to undo the screw.
1. Use a pointed tool such as a bradawl or a knife to scrape paint out of the slot or recess in the screw head, so that the screwdriver tip fits it properly. Then try to undo the screw.
2. Before attempting to undo a rusty screw, place the screwdriver in the slot or recess and strike the end of the handle firmly two or three times with a hammer.
This often breaks the grip of the threads in the wood and makes it easier to undo the screw. With slotted-head screws, try angling the screwdriver blade in the slot before you strike its handle. This will turn the screw slightly and should have the same effect.
3. If the screw head is damaged and the screwdriver tip will not allow any torque to be applied to it, you will have to drill it out.
Fit a twist drill bit about half the diameter of the screw head in your drill.
Hold it against the centre of the screw head and drill slowly into it.
When you reach the screw shank, the drilled-off head will spin off on the drill shank. Continue drilling until you have completely drilled out the screw shank, and separate the components it was securing.
Alternatively You can use a screw extractor—a threaded bolt that fits the chuck of a cordless drill. It is screwed into a pilot hole drilled in the screw head, and is then reverse-driven to draw out the damaged screw.
Removing old nails
Because nails are driven flush with the surface, removing them without damaging what they are fixing is almost impossible.
1. The best approach is to try to prise away whatever the nail is securing—for example, by levering up a floorboard or pulling a skirting board away from the wall. One of two things will happen.
2. The nail head may be lifted slightly, allowing you to grip it with a claw hammer or pincers or nail pullers and pull it out. The website ToolsDiary has reviewed nail pullers which is worth checking out to learn more.
3. Often the nail will not move but will tear through the material it is fixing, allowing you to remove this and then tackle the exposed nail as before.
Use this approach to remove old carpet that has been tacked down, to tear hardboard off an old panelled door or to pull plasterboard away from partition walls and ceiling joists.
4. You can try another approach if it is not essential to remove the nail. Use a nail punch and hammer to drive the nail head through the material it is fixing so you can free it.
This is the best way of lifting old floorboards that are to be saved and re-laid, as it minimises damage to the boards.
5. If large nails have been used to assemble a framework—in a partition wall that is being demolished, for example—it may be possible to free the fixings by knocking the individual joints apart.
The nails are often driven in at an angle in structures of this sort, and a few carefully aimed blows with a club hammer will open up joints and make them easy to separate.