How to Use Magnets to Locate Studs

Learn how to use a simple magnet to locate timber studs. Timber stud walls are often clad with a baseboard/plasterboard/thin timber, fastened either with nails (clout nails or pins) or more recently with drywall screws. These metal fixings can be located by utilizing their magnetic properties.

Steps

Using a Magnet

1. Take a powerful magnet and place it on the wall surface.
   
2. Move the magnet around in a logical grid type pattern over the surface of the wall; feeling for a slight 'pull' on the magnets passage over the walls surface.
   
3. The feel or strength of the 'pull' will depend on the power of the magnet.
   
4. Mark the wall where the magnet indicates that there may be a fixing.
   
5. The indicated fixing points show where the timber stud is located behind the cladding, as fixings are usually close to the center of the timber stud.
   

Making a Stud-Finding Pen

1. Choose a strong magnet. The strongest readily available magnets are neodymium magnets, also known as rare earth magnets. You can use any size of magnet, but a small one will work fine (say 1 cm / 0.4 inches).
   
2. Enclose the magnet in heat shrink tubing. Place the magnet inside heat shrink tubing of the appropriate diameter. One flat surface of the magnet should be visible. This gives the magnet a flexible wrapper, making it easy to manipulate.
   
3. Seal the heat shrink tubing. Heat the heat shrink tubing until it holds the magnet securely in place.
   
4. Glue the tubing into an empty pen case. Take the inner components out of an old, pen. Place the heat shrink tubing inside the pen, with the magnet poking out at one end. Hot glue it in place. The pen case will give you greater control over the magnet's position, and reduce the effect your hand has on the magnet's response.
   
   • Test the pen case first to make sure it does not repel or attract the magnet.
5. Test it out. Hold the pen very lightly, such that the tip is free to move. Now test it out against a wall. Move vertically, then horizontally to find the stud. Once you find a stud, mark the wall with a regular pen to note its position.
   

Tips

• Try to predict where the next fixing may be; many tradesmen are quite accurate in their spacing when fixing, typically around 150mm-250mm apart for drywall.
• Wrap the magnet with a tissue or light cloth to avoid marking the wall if it has a painted or other decorative surface.
• Use a tiny blob of "Blu-Tack" or similar tack to mark the indicated fixing locations that 'pull' the magnet on finished walls.
• Try logical places first, around the edges for example.
• To find the width or outer edges of a timber stud, drill a horizontal series of small holes (say 3mm), 10mm apart, across the face of an indicated timber stud. Where the drill bit runs straight through the cladding, will show you the edges of the timber stud. If you feel resistance once through the cladding you are still over the timber stud.

Warnings

• Using a magnet to find fixings fastened into timber studs will not locate or indicate any other services in the wall; for example: electrical cables/wires; communication cables/wires; copper piping; plastic piping etc.
• Not feeling the magnets pull does not indicate that there is not a fixing present. The fixing may be too deeply buried for the magnet to affect it or the magnet you have is not powerful enough to pull such a small amount of metal fixing.
• Always check for services buried in walls before drilling into them; drilling into live cables can be very dangerous.
• As a precaution, consider isolating the power supply to the work area before drilling into a wall and use cordless tools or extension cables to an alternative power source.

Sources and Citations

• Image of typical timber stud walling taken from Ian Anderson's website.

from How to of the Day http://ift.tt/1hrksXV
via Peter