Self tapping southwire ground screws

[bluedog225]

Are those compliant with NEC? Seems like TEK screws are not. But I don’t see much difference. I like to be in the neighborhood of code compliance.

I think most of my boxes will accept a regular machine screw but I was curious.

Thanks

 

[sparky 1971]

Yes. Metal boxes have a raised hole for them and the screws will cut their own threads. I don't remember what the code book says but there are supposed to be so many threads engaged in the box; the grounding screws are a 10-32 and fit the bill. I doubt if more than one thread is in contact if a a Tek screw is used, but I may have done it in the past.

 

[mm08822]

 

[PCustoms]

...but I may have done it in the past.

Next you'll tell us you cleaned up when done!

 

[JohnX14]

Next you'll tell us you cleaned up when done!

LMAO!

 

[sparky 1971]

Next you'll tell us you cleaned up when done!

Never. Unlike others on GJ, I try to keep my stories somewhat believable. And I don't want to get my broom dirty; it's still in pristine condition after32 years.

 

[JohnX14]

Never. Unlike others on GJ, I try to keep my stories somewhat believable.

I will spot you, from someone who just started frequenting this place, that your stories are generally believable...

 

[dscheidt]

Yes. Metal boxes have a raised hole for them and the screws will cut their own threads. I don't remember what the code book says but there are supposed to be so many threads engaged in the box; the grounding screws are a 10-32 and fit the bill. I doubt if more than one thread is in contact if a a Tek screw is used, but I may have done it in the past.

code requires two threads in contact, and requires boxes to be at least 1/16" thick, so 32 tpi screws meet the requirement

 

[alfredeneuman]

Self tapping screws differ from regular machine screws in that they have a fluted tip that clear the chips away before the the machine screws start
if the proper size pilot holes are drilled...in theory.
Realistically it is a different story (and quite frustrating, with about a 1 in 10 success rate).
I run a 10-32 tap through the hole as a matter of course.

 

[rlitman]

Self tapping screws differ from regular machine screws in that they have a fluted tip that clear the chips away before the the machine screws start
if the proper size pilot holes are drilled...in theory.
Realistically it is a different story (and quite frustrating, with about a 1 in 10 success rate).
I run a 10-32 tap through the hole as a matter of course.

Kind of. The self tapping screws also roll the thread more than a tap, which pretty much only cuts. So you'll get better thread engagement if you use a self tapping screw first. Then toss that screw (because it's threads are likely munged after it's first use) and insert a second self tapping screw.

 

[Codyboy]

I bought a box of Gardner Bender ground screws and yeah they are hit or miss.
The heads round over easily. I assume its because china.
There's not much length on the hex head and difficult to get a good purchase on it.

Make sure the hex bit your using is in good shape and be certain you start it square to the hole.

 

[sparky 1971]

I bought a box of Gardner Bender ground screws and yeah they are hit or miss.
The heads round over easily. I assume its because china.
There's not much length on the hex head and difficult to get a good purchase on it.

Make sure the hex bit your using is in good shape and be certain you start it square to the hole.

I use GB screws almost exclusively because that's what Menards has on the shelf and I can never remember to pick any Dottie's up at the supply house. Over 90% of them that I install are run in with a Phillips bit on an inline cordless screwdriver; I can't say that I've ever had a problem. Why Phillips? because that's what the box screws are and I'm either installing a mud ring or raised cover at the same time. I also use P2 for the device screws.

 

[dcg9381]

code requires two threads in contact, and requires boxes to be at least 1/16" thick, so 32 tpi screws meet the requirement

Number of home inspections that caught this violation in the last 10 years: Zero.

I like to be in the neighborhood of code compliance.

I've learned more from the NEC arm-chair code guys here that I'd ever learn as a real sparky-apprentice. No complaints from me.
If you can pass a GJ inspection, you're good to go.

 

[mm08822]

Yes. Metal boxes have a raised hole for them and the screws will cut their own threads. I don't remember what the code book says but there are supposed to be so many threads engaged in the box; the grounding screws are a 10-32 and fit the bill. I doubt if more than one thread is in contact if a a Tek screw is used, but I may have done it in the past.

Does anyone remember the fun of tightening those screws in a 4/5" sq box when the raised dimple didn't exist?

Not only could you trash the screwhead but even strip out the hole if you didn't use an awl or drill in a relief before mounting box.

 

[bluedog225]

Does anyone remember the fun of tightening those screws in a 4/5" sq box when the raised dimple didn't exist?

Not only could you trash the screwhead but even strip out the hole if you didn't use an awl or drill in a relief before mounting box.

Yep. Still have a few.

 

[rlitman]

Does anyone remember the fun of tightening those screws in a 4/5" sq box when the raised dimple didn't exist?...

Nah, before the raised dimple, I had those stupid ground clips that held your pigtail to the box rim.

 

[mm08822]

Nah, before the raised dimple, I had those stupid ground clips that held your pigtail to the box rim.

I still have hate for this type