6

A previous owner of my house (I swear it was not me :) ) appears to have broken off a screw in the hole (red circle) that allows the bottom of the outlet to attach to the box, leaving only the top hole (yellow circle) free to attach the outlet to. What's the best way to get the screw out? I know that one option is described in Removing broken screw from electrical box, but I'd like to preserve the existing threads if possible. I tried grabbing it with needle-nosed pliers from the front and twisting it out, but it appears stuck either via corrosion or because it's the wrong size (although they did get it in that far). I was thinking of trying the following approach:

  • apply WD-40 to the hole in the front and back to loosen up any rust
  • try grabbing it from behind the hole with curved needle-nosed pliers and see if I can at least move it out a little bit farther
  • if I can move it with the pliers, either unscrew it all the way, or get it out far enough that I could cut a groove in it to put a flathead screwdriver in

I could just try cutting the groove now, but that seems risky given that it might be stuck in there pretty well if it's the wrong size, and I don't currently have a lot of room for error if I cut it incorrectly.

What do you think? Thanks in advance for any help!

enter image description here

0

3 Answers 3

15

Corrosion isn't your problem. The screw was too long and it bottomed out on what looks like a cable clamp in the box. The screw is in compression. If you get in there with a Dremel with the tiny cutoff wheel, you should be able to saw through it. Once you do the compression will be gone and you should be able to finger-spin it out.

It looks like his mistake was using extra long screws because of the depth of the plaster there. And he went extra extra long, and was too long and bottomed out. Choose length more carefully, or use the feature on your wire stripper to cut bolts.

1
  • 1
    that was totally it. I cut the back part off and actually had to force the cut off piece out with pliers it was in there so tightly. Once I did that the screw came out easily with the help of some pliers. Good catch! Commented Aug 17, 2017 at 0:38
2

You'll probably have better luck with vise-grips than needle-nose pliers. After that, I'd hit it with something like liquid-wrench, specifically formulated to break up corrosion, or a penetrating oil. WD-40 isn't the best lubricant.

This would be tricky to do, but as a second option you could remove a little more drywall (to make space) and see if you can tighten a drill chuck around the screw. A hand drill has a lot of torque, and should break the seized threads free.

4
  • even though it's rather tight in the box, the vise grips (generic term, locking pliers) idea may be your best shot for good grip. Crank it down as far as you can when you lock the pliers. You'll have only a few degrees of movement and the pliers will scar the threads but once you get the thread out far enough to grip, consider to use a rotary cutter (brand name, Dremel) to cut away the inner portion. If rust is a factor, flip a compressed air can upside down and spray the cold liquid on the bolt at the hole. The thermal shock may free things up along with your task-specific penetrating oil.
    – fred_dot_u
    Commented Aug 16, 2017 at 0:18
  • If you use ench's suggestion to enlarge the drywall hole a bit, you may also have enough thread on the outside now to grip with good quality locking pliers, reducing all the rest of the labor substantially.
    – fred_dot_u
    Commented Aug 16, 2017 at 0:19
  • @fred_dot_u Good catch on damaging the threads. If you can't lock the pliers around the outside portion, you could try covering the jaws with a layer of masking tape. That'll reduce the marring, but may reduce your gripping power as well.
    – ench
    Commented Aug 16, 2017 at 0:22
  • Thanks to you both for great suggestions. @ench would long nose locking pliers (aka long nose vise grips) be appropriate here? My normal set of vise grips are too big to fit all the way past the hole in the drywall to grab the screw from the back. Commented Aug 16, 2017 at 0:30
0

If you need to cut it you can but all you need to do is continue tightening it until it clears the hole. Or you can always drill it out any if you need to rethread the hole just find a larger screw and a tap and die kit. It's only a few threads I'd just use vice grips and force it through.

1
  • 2
    Also wd-40 is not the most effective penetrant. I generally start with pb blaster and if ineffective I move to jb-80 but it's 3x the cost
    – Derek
    Commented Aug 16, 2017 at 7:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.