How to fix a plug socket whose screws don't hold anymore?

Question

I removed the screws of the socket (as shown in the image) to check something, and when I tried screwing it back in, the screw wouldn't hold anymore. It just keeps coming off.

I tried sticking the socket back using superglue at the edges, but when I plugged in a water heater and pulled out the plug, the socket got un-stuck again. It's the same with any of the sockets at home. If we remove the screw once, we cant screw it back in again because it doesn't hold.

Is there any way to fix this?

Answer 1

As tacky as it is, I have seen electricians use drywall screws to hold receptacles when the threads are stripped out. the sharp threads of the drywall screw will cut new ones into plastic or thin metal. If your screw goes into a brass insert molded in the plastic, you may be out of luck. Do be careful of the length of screws used, the sharp points will go into a wire with no resistance, shorting out your connections.

Answer 2

Turns out that it actually was a nut and bolt fixture.

Got an opportunity to turn off the mains and when I opened it up, this is what I found:

Dad said those existing nuts and bolts aren't so good, and gave me better ones with washers which I used:

and now it stayed put:

The nuts and bolts on the right were the ones the contractor used, and the ones on the left are what Dad gave me today.

Answer 3

You should shut off the power and remove any attached devices from the outlet prior to doing any work on it.

Either the screw is not reaching the threads, or the screw/box threads are stripped. If the screw is not long enough or the screw is stripped, then the solution is simple - go get a new, longer one.

If the threads in the electrical box are stripped, you can cut new, larger threads using a tapping tool and then use the next screw size up.

Klein Tools 6-in-1 Tap Tool quickly forms new threads and re-forms burred threads. It's also great for cleaning out plaster obstructions. Each tap size rethreads to the next larger size if threads are stripped.

Souce: http://www.homedepot.com/p/Klein-Tools-Cushion-Grip-Six-in-One-Tapping-Tool-626/100630874

_{(source: homedepot.com)}

Be careful to avoid damaging any wires that you might come in contact with.