Introduction: How to Use a Magnet to Find Studs

Picture of How to Use a Magnet to Find Studs

Electronic stud finders have never worked for me. I'm either working on a plaster and lath wall where the stud finder has no hope, the wall is textured, or there's a bunch of other junk in the wall throwing off the sensor. After wasting time, ever hopeful that it will work this once, I have always ended up just drilling holes to find studs. Good thing I'm good and Christy's great at patching plaster and drywall.

Before electronics made our lives easy, people found the nails or screws in studs with a magnet. I tested this trick out in comparison to an electronic stud finder while installing a set of shelves, and it's doubtful I'll ever use my electronic stud finder again.

Step 1: Grab Magnet From Fridge, Hang With Dental Floss

Picture of Grab Magnet From Fridge, Hang With Dental Floss
I grabbed a plain magnet from the refrigerator, and tied a piece of dental floss to it -- any fine string or thread would work. Dangling the magnet along a wall revealed all the nails and screws in or beneath the drywall. Once I marked a few with a pencil, it was obvious where the studs were.

I've read that people find this method too slow, but the electronic stud finder always leaves me guessing. Once I saw the pattern of fasteners there was no question I had found studs. If you want to speed the process up, a strong and light rare-earth magnet would really seek out the nails.


3366carlos (author)2017-01-21

nice, a strong magnet would be better.

MagneoSmartM (author)2016-04-30

you need rod magnets - like this 10x20 mm

abarrundia (author)2015-01-08

nope, as crazy as it sounds, it didn't work for me. My apt was built in 1925 and I don't know what's going on behind those plaster walls but the magnet just sticks to every single spot. I already drilled a hole to the point the magnet stuck the strongest to find nothing. I really don't know what else to do.

Mastamoe (author)abarrundia2016-04-03

In my experience:

All plaster walls have a wire lath behind which is esentially chicken coop mesh. Imagine a chain link fence but really tiny holes. They used it so the plaster has something to adhere to. To anchor something to a plaster wall, toggle bolts are your best friend.

woohizzle (author)abarrundia2016-02-05

Some early 20th century apts do not use studs and drywall, but rather gypsum block and plaster. This may be the case and you may not have any studs at all. Depends on the building.

Camdarhar (author)2015-12-16

After listening to my FRUSTRATED HUSBAND with his stud finder that wasn't working and knocking, I decided to google it and found this. I found the studs in seconds, said your welcome and walked out of the room with a huge smile on my face :) Man ego went down the tubes in a hurry, so I thank you for that!! Awesome

The_Conqueror_Worm (author)2015-12-11

This worked great! The first nail took a little while to find, but once I found the first one it went really quickly. Thanks!

MiaS1 (author)2015-05-31

Excellent!! Thank you! I've been knocking on the wall to no avail. It all sounds hollow. This was the best method!! Found the screws in the studs in seconds.

jo8 (author)2015-05-10

This was perfect. I spent ten minutes trying to use a stud finder, another ten trying to find the directions for the stud finder b/c I couldn't remember what the light meant. Found this and five minutes later I had all my studs marked in my closet. Thank you!

connie.pinkert (author)2015-02-22

Cant wait to try this..Need to hang a large framed mirror...Thanks

agnpros (author)2015-02-02

This worked easily for me. If you are using a weak magnet, you may need to find the side that is attractive and make sure your magnet is laying against the wall on the correct side. But it works. It's magnets. It has to work. Thanks man.

Best_Consumer (author)2014-10-08

This is pretty cool information. We spend a lot of time recommending products on the market mainly big brands to people. But for some people who may need to use a stud finder maybe once or twice a year, this works. Its a good way to teach kids about what stud finders whats in walls, wall safety, I know my 7 year old loves magnets. We cant review magnets but this was insightful.

winchester883 (author)2007-09-16

What about pipes and other such stuff that might be in your walls? wouldn't the magnet pick up on them as well?

kyles3 (author)winchester8832014-09-16

it is possible to find cast iorn, galvanized, or electrical shield piping. but normaly these pipes should not be continuously touching the dry wall.

ewilhelm (author)winchester8832007-09-17

A magnet isn't going to pick up copper or PVC pipes, which is probably the majority of piping materials. If you had an iron pipe in your wall, from a stream heating system for example, it would be obvious you had found a pipe rather than a bunch of nails in a stud.

el_darwin (author)2014-01-19

This is so simple and elegant, will do it next time

cart562 (author)2013-11-22

Alas, I wish I had known this time, next time....

Father Christmas (author)2009-03-04

or you could stick with the time tested method of knowing what you are doing before you start putting hole sin your walls. at least, that is what i do. with practice, a quick knock on the wall is all that is needed to know if a stud is there.

Bannef (author)Father Christmas2013-08-12

But I'm not going to know what I'm doing though until I figure out how things like studs work - this method can give me an idea of how my house is put together without actually putting holes in anything.

Try that with a plaster and lath wall.

You've clearly never worked on a plaster and lath wall.

aye, that much is true.

rantipole (author)2012-09-20

Don't Know why I didnt realize this on my own. I have tried every different method - Knocking, Running a Electric razor over the wall (resonance), Magnets plain old makes sense to me. Thanks!

mazelady (author)2012-02-08

I wonder if this would work over tile? We have the old 4x4 tile and I need to find the studs so I can install a grab bar.

jmiller1946 (author)2011-12-01

Most magnets won't work - go to place like K and J magnetics and get a neodymum magnet for about $3 or $4 - 3/8 in x 3/4 in
it wil then work like a charm

joblake326 (author)jmiller19462011-12-09

check out the studthud. It's magnetic. It is supposed to work on everything from sheetrock to tile to wood lath. It's just starting to sell in Australia but site says it'll be available in U.S.early 2012.

bmcguinness (author)2011-10-06

I saw a similar ('magnet on fishing line') approach elsewhere before I saw this one, grabbed a couple of strong magnets 1/4" dia, 1/8" thick from one of those therapeutic back (etc) supports I have, put them together, dropped them in a doggy poo bag, dangled it around and it worked like a charm - instantly. Scared hell out of my wife, though, when I left the bag hanging on the bedroom wall and she thought a black bat had invaded. Woops.

BottomlessPizzaPit (author)2010-11-10

I made something similar to this years ago with thin gauge wire and -as you mentioned- a rare earth magnet. My mother works in the dental field so we had a surplus of Sonicare toothbrush heads around and I popped one off of there. Saves time whereas some electronic ones will freak out about all sorts of staples and former painting hanging devices embedded in your walls.

Bartboy (author)2010-06-25

I just use my hand, without bothering to use string.

eyerobot (author)2010-06-20

I used this idea with a strong hard drive magnet, And a plumline. Once I found the top of the stud, I pinned it, And found the bottom of the stud, then one quick snap of the chalk line showed the entire stud. this is one of those great ideas, that cant be surpassed by anything but an Xray.

mlucas719 (author)2010-06-10

i don't get this what if i have wooden studs?

awfeckit (author)mlucas7192010-06-10

Yes, wooden studs. If you live in a house as opposed to an apartment building, you probably have wooden studs. The magnet is not attracted to the studs. It's attracted to the steel nails or screws that are used to hold up what ever material is covering the studs. You find the nails with the magnet. You mark the spots where the nails are. That means there is a stud behind that spot. Mark the two nails vertically in the wall and use a straight edge to mark where the stud is.

camp6ell (author)mlucas7192010-06-10

like two short planks you mean...?

ZackBlack (author)2010-06-10

In the old days before electronic stud finders the "stud finders" were simple units made from plastic with a magnet that freely moved inside it. The magnet would be attracted to the nails in the stud and would rock forward towards the stud and vola - you found the stud! This 'ible works on the same principle.

jeff-o (author)2010-05-27

I have to try this the next time I have to hang shelves on my walls.  I've got an older house, and my electronic stud finder seems to get confused...  a lot.  It has no trouble with new drywall I've installed, though.

shawnlogan (author)2010-04-16

great idea, I'll have to try it; I have some old dead HDDs at home. Although, some plaster and lathe walls are so thick and textured this might not work unless you have a very (very) strong manget. I know that some of my plaster walls are nearly 3/4 inch thick.

gomezr1 (author)2008-07-13

I didn't even finish reading this instructable and immediately started checking for studs on my walls...AND IT WORKS!!! Thanx for sharing such a simple alternative to an otherwise expensive (if you had to buy a stud finder like I would) and overly complex device i.e. too much technology for a minimal task.

funwithfire325 (author)2008-04-04

took my next Instructables..

ichipoodle (author)2007-12-28

Yep, great instructable! but, i make it easy to test whether an electronic finder is working. *holds near torso* *beeep!* hey! it works!! lol, just kidding. but really, this is super simple and easy! although... about the metal mesh comment, do you think it'd be there on a house built in the '50's? because my house is a fixer-upper =\ always have to fixer this or upper that, it gets annoying. heck, one time i had to solder copper pipes near my second bathroom and had to itch my leg; i moved while prone and stabbed my scalp on a nail! ouchies....

cfryxell (author)2007-10-03

This is the smartest thing i've ever seen! how genius. I hate my stud finder it just beeps at me randomly, thanks so much!

Raster (author)2007-09-20

Kill-a-Watt has the best angle on this - pull them out of a hard drive. Nearly everybody has one that's too small, or has crashed. If you don't have the weird screwdriver bits, you can always drill the screws out, and there's a pair of magnets in there that are crazy strong! Great idea, works like a charm!

zachninme (author)2007-09-17

I've seen people recommend magnetic (NdFeB) spheres for finding nails in the floor (roll them!). This obviously won't work with the wall, but maybe taking a handful of these and throwing them at the wall will help. (These guys rock, BTW, and they're not as bad to loose @ $0.06 apiece for 100pc, its only 5 cents when you buy in 500, and 4 cents in 10K quanities...)

zachninme (author)zachninme2007-09-17

Just a note on my magnets:
These are the same price as the above ones, if you buy 100 of them (What, you wouldn't? Its $6!) They're 11x as big, but pull 5x as much. (I know that doesn't sound good, but considering 5x as much for 1x the cost?)

And I should note if you don't like the size, these are same pull force, and ever-so-slightly heavier. Not to mention cubes.

Sorry for spam :P

kill-a-watt (author)2007-09-17

I've used an old hard drive magnet before. I just lightly slid the magnet over a 2x2' foot area until I found one. Then I would sweep up and down the stud and find the others Holding the magnet lightly in your hands would pinpoint the exact head of the nail. In my case I had drywall with nail pops, so I decided to find every single nail, punch it below the drywall with a pin-punch and add two drywall screws above and below each nail. Then I would spackle and repaint. I found that a stud sensor did in fact work, but for my job I actually needed to find every nail anyway.

ranex (author)2007-09-17

last time i used an electric stud finder i almost drilled through a pipe- all you'd have to do would make sure it only stick to that one spot instead of in a line

oskay (author)2007-09-16

I've done this for years-- works like an absolute charm. I heart NdFeB magnets. =)

uncle_al_0 (author)2007-09-16

Great idea but i think if you used a rare earth magnet you might have problems on plaster walls with metal mesh backing. Some carpenters use it when repairing some holes in the plaster walls. If you used a weaker magnet then you probably wouldn't run into that problem.

About This Instructable




Bio: Eric J. Wilhelm is the founder of Instructables. He has a Ph.D. from MIT in Mechanical Engineering. Eric believes in making technology accessible through ... More »
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