hello,i need to replace a existing electrical box with a bigger one in order to install a gfi.the old box is metal from the 1950s.it is to small.does anybody have any sugeestions how to remove the old box without hacking the wall up.its a plaster wall with lath.jvl
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You'll likely have to increase the opening slightly to fit in an old work box (the kind with the ears that snug up against the outside of the wall by tightening the screws). I've never owned a house with plaster lath, so take that for what it's worth.
To get the existing metal box out, I use a pair of tin snips, a small sized flat head screwdriver and a phillips. The metal boxes are usually suspended via a pair of metal strips at the top and bottom of each box, and that run to the nearest stud.
In the gap between the top and bottom of the box and your plaster, see if you can reach the flat head screwdriver tip in (sideways, not in the normal fashion of driving a screw) and start to loosen the box from the metal strips. There should be one screw on the top and one on the bottom that hold a pair of metal ears, which in turn slide into a slot on the metal bar.
If you can get these screws out, you can tilt the box enough to get at the phillips screws that hold the box pieces themselves together.
Once you get the box out, use the snips (and several different varieties of snips can be handy here - left side, right side, etc.) Cut the metal bars as close to the studs as you can. If you can get a cats paw in there to pull the nail securing the strip, even better.
Hope that's helpful.
Edited 12/4/2007 8:17 pm ET by FatRoman
Would it be feasable to use the old box as a junction and just put a new box nearby?
I know this would be a last resort but i can tell you that of all the walls I cut into plaster on lath is the most unstable. If its good its good, but if the plaster is starting to loosen up on the lath you can quickly find yourself with a load of plaster on your shoe.
Maybe try (carefully) to cut the ears with a sawsall. Before you do this make sure you know where the wires are.
As someone else mentioned these boxes actually are about 1" away from the studs and have brackets top and bottom that attach to the stud.
Good luck.
Have your larger box handy to take measurements from. Cut the hole for the new box and use the extra space to mangle the old box enough that it can be taken out.
Depending on how it's attached I'll first try to get the wires pushed out of the box so they won't get mangled in the process. Then a flat bladed remodler (japanese) bar is used as a cold chisel and I'll try to knock the box sideways and tear it loose of either the lathe or framing, depending on what it's attached to. Often the box will come loose and can be left in the stud cavity with little damage to the surrounding area. If there are a lot of boxes a 2 lb engineer's hammer and larger cat's paw can sometimes be more agressive and faster.
It all depends on how it was put in and how much abuse the plaster can handle.
Good luck
Beer was created so carpenters wouldn't rule the world.
cut the size hole in the wall for the new that you'll need with yur multimaster
cut the nails holding the old box with yur multimaster...
pull the old box..
install the new....
use appropiate cutters for the material being cut...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
I like that, it's the best approach, kind of like doing brain surgery.
it works like a champ...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
I would have tried a 32T blade on a sawzall, but your MM suggestion is much less likely to damage surrounding lath and plaster.BruceT
yup..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
Assuming the box is nailed to the stud, I'd generally push the wires out of the box and then use a pry bar to work the box loose. Doesn't even have to be removed, you can just let it drop in the stud cavity.
But a lot depends on the particular box and how it's attached. If you have one that's screwed together you might be able to drill out the screws, eg, to get rid of most of the box.
Another option is to work a sawzall between the box and stud, but you obviously gotta be careful of the wires.
Another hint: Decide that you really need to replace the box with a double. Gives you lots of extra room to work with.
thanks everyone for the cerebral stimulation.ive got all the tools but lack the experience.onwards jvl