attach plastic box with metal screw through side ?

[RustyShackleford]

Even if it's allowed (screws through the near side of a plastic box into the neighboring stud), the several boxes suggested earlier in this thread seem like a much simpler way to achieve the same purpose (than drilling the holes yourself and contriving to be able to drive the screws at an awkward angle).

But certainly I don't see much difference, electrical safety wise, between the DIY approach and those boxes.

 

[jetlag]

No Can do

No Can do

A metal screw can not exit thru a plastic box because it is not grounded , but believe me it is done every day . I have been guilty in a tight before myself . Some are confusing this with a metal box in which the metal screw would be grounded against the box . The exception is if the plastic box is approved and designed with the metal screw recessed to avoid contact with live conductors . I am sure someone will say " show me the code" and I will have to come back and look it up. It is probably in one of the codes already mentioned.

 

[Little Bill]

A metal screw can not exit thru a plastic box because it is not grounded , but believe me it is done every day . I have been guilty in a tight before myself . Some are confusing this with a metal box in which the metal screw would be grounded against the box . The exception is if the plastic box is approved and designed with the metal screw recessed to avoid contact with live conductors . I am sure someone will say " show me the code" and I will have to come back and look it up. It is probably in one of the codes already mentioned.

I'm afraid you are going to have to come back and look that up! Then leave, come back, then try again!
Don't think you're going to find it.:happyno:

 

[iwire]

A metal screw can not exit thru a plastic box because it is not grounded ,

If that screw needs to be grounded why don't NM staples need to be grounded?

 

[infinity]

A metal screw can not exit thru a plastic box because it is not grounded , but believe me it is done every day . I have been guilty in a tight before myself . Some are confusing this with a metal box in which the metal screw would be grounded against the box . The exception is if the plastic box is approved and designed with the metal screw recessed to avoid contact with live conductors . I am sure someone will say " show me the code" and I will have to come back and look it up. It is probably in one of the codes already mentioned.

I agree and if the screw became energized it could even energize something outside of the box. Take a small isolated section of wall built with metal studs and attached to wood overhead. The plastic box is attached to the metal stud with a screw, the screw becomes energized and the metal portion of the wall becomes energized. Then the metal corner beads on the wall become energized. You wouldn't even need to open the box to be exposed to a hazard.

 

[Dennis Alwon]

My solution to this is to add a bit of duct seal or silicone on the screw head thus keeping it isolated from being energized.

 

[1793]

My solution to this is to add a bit of duct seal or silicone on the screw head thus keeping it isolated from being energized.

There also is Liquid Electrical Tape to apply to the screw heads.

 

[1793]

A metal screw can not exit thru... with live conductors . I am sure someone will say " show me the code" and I will have to come back and look it up. It is probably in one of the codes already mentioned.

Look at 314.43 I think. I stole this from post #17 of this thread.

 

[ActionDave]

I agree and if the screw became energized it could even energize something outside of the box. Take a small isolated section of wall built with metal studs and attached to wood overhead. The plastic box is attached to the metal stud with a screw, the screw becomes energized and the metal portion of the wall becomes energized. Then the metal corner beads on the wall become energized. You wouldn't even need to open the box to be exposed to a hazard.

And it would probably mess up the paint.

 

[jetlag]

thanks You Got it 1793

thanks You Got it 1793

Look at 314.43 I think. I stole this from post #17 of this thread.

Thanks now I dont have to find it and if any one can't understand 314.43 then I won't bother to argue back. That is the pupose of making the plastic remodeling box with the 2 dry wall screws already installed inside the box that go in a recessed mounting hole .

 

[Little Bill]

A metal screw can not exit thru a plastic box because it is not grounded , but believe me it is done every day . I have been guilty in a tight before myself . Some are confusing this with a metal box in which the metal screw would be grounded against the box . The exception is if the plastic box is approved and designed with the metal screw recessed to avoid contact with live conductors . I am sure someone will say " show me the code" and I will have to come back and look it up. It is probably in one of the codes already mentioned.

I'm afraid you are going to have to come back and look that up! Then leave, come back, then try again!
Don't think you're going to find it.:happyno:

Look at 314.43 I think. I stole this from post #17 of this thread.

Thanks now I dont have to find it and if any one can't understand 314.43 then I won't bother to argue back. That is the pupose of making the plastic remodeling box with the 2 dry wall screws already installed inside the box that go in a recessed mounting hole .

That isn't what you said. You were saying the reason was the screw wasn't grounded. That's why I said you wouldn't find that in the code. So.......

 

[iwire]

That isn't what you said. You were saying the reason was the screw wasn't grounded. That's why I said you wouldn't find that in the code. So.......

I agree with Bill, there is nothing that requires mounting hardware to be grounded.

 

[kwired]

I get the possibilities if you have a metal stud, now what is the danger with a wood stud?

 

[Dennis Alwon]

I get the possibilities if you have a metal stud, now what is the danger with a wood stud?

Probably nothing unless the wood was wet. The code has to look at all possibilities and it is virtually impossible to list all the exceptions where it may not matter. The fact is the NEC does not want energized parts outside the box. Think of a remodeling job where someone can get very hurt.

 

[kwired]

Probably nothing unless the wood was wet. The code has to look at all possibilities and it is virtually impossible to list all the exceptions where it may not matter. The fact is the NEC does not want energized parts outside the box. Think of a remodeling job where someone can get very hurt.

You can not protect from every possibility. I bet I have seen many more times where someone on a remodel job was exposed to danger by cutting into a raceway or cable containing energized conductors than I will ever see someone at risk of shock from a wet stud that somehow became energized. That stud has to be pretty saturated to become much of a conductor with only 120 volts applied. I doubt even green treated lumber that is typically high in moisture content conducts very well at 120 volts. And yet it likely will have higher conductivity than non treated just because of what they may treat it with.

 

[ActionDave]

You can not protect from every possibility. I bet I have seen many more times where someone on a remodel job was exposed to danger by cutting into a raceway or cable containing energized conductors than I will ever see someone at risk of shock from a wet stud that somehow became energized. That stud has to be pretty saturated to become much of a conductor with only 120 volts applied. I doubt even green treated lumber that is typically high in moisture content conducts very well at 120 volts. And yet it likely will have higher conductivity than non treated just because of what they may treat it with.

I had the EGC from a piece of romex come into contact with a live buss. The EGC was bonded to a metal box screwed to a wood stud, everything else was clear. It turned bright red, burned for about one and a half seconds and about one foot of it turned to dust. The wood was not wet. Why it drew enough current to do that is a mystery to me.

 

[iwire]

We attach NM to metal studs with Caddy CJ-6 which are metal do they need to be grounded?

 

[ActionDave]

We attach NM to metal studs with Caddy CJ-6 which are metal do they need to be grounded?

Cad weld a #6 to the studs and run it back to water pipe and you are good to go.

 

[Dennis Alwon]

We attach NM to metal studs with Caddy CJ-6 which are metal do they need to be grounded?

Of curse not no more than should a metal staple but the strap is outside the box where it won't get energized

 

[guschash]

HD has old work boxes that will fit into a single gang cut out , take out old box and fit this box in same hole that is actually a two gang box. Hard to explain but it's like a two gang box with a mud ring for single gang.