I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?


Thank you.

"redbrickhat" wrote in message
ups.com...
I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?

If you are sure the box is grounded, then you can drill a hole and run a
self-tapping screw into it.

I'd doubt that the box is grounded, based on what you posted.

redbrickhat wrote:

I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?


Thank you.

hmm.
don't know exactly what you're talking about but i'll assume
maybe an house whole panel? If so, go to your local electrical supply
shop and get a grounding Bus strip. Attach it good to the panel and
attached a direct ground from the outside to this bus strip also.
attaching a single ground to a box that you do not even know if it
is grounded to start with, is not a good idea.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

Standard box grounding screw is 10/32


"redbrickhat" wrote in message
ups.com...
I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?


Thank you.

Charles Schuler wrote:

"redbrickhat" wrote in message
ups.com...

I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?


If you are sure the box is grounded, then you can drill a hole and run a
self-tapping screw into it.

I'd doubt that the box is grounded, based on what you posted.


I agree. If it were grounded, there's little chance the ground
would be "weak," because the outlet's ground would already be
connected to the box via its mounting screws.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

In article . com, "redbrickhat" wrote:
I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

Not sure I understand... Why is the ground "weak"? And why do you believe this
will fix it?

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

Code requires that the screw holding the grounding wire may not be used for
any other purpose. So if the hole you're proposing to use is already in use
for mounting the box, or attaching a cable clamp, then the answer is no.
Otherwise, yes.

Also no reason (given the appropriate tools) why you couldn't drill and tap a
new hole for standard 8-32 grounding screws.

B) What size screws fit the larger holes?

Usually 10-32.

C) Would any normal screw metal type work?

No -- you want a screw with a pan head, round head, or washer head. Flat head
and oval head will not hold the wire securely.

You'll find that something with a Phillips or Robertson (square drive) head is
easier to install than a slotted head.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

"RBM" rbm2(remove wrote in message
...
Standard box grounding screw is 10/32


The old black boxes didn't have a ground screw tap, but the screw holes for
the clamps were 10/24. You could try retapping one of those with a 10/32
tap.



"redbrickhat" wrote in message
ups.com...
I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?


Thank you.

On 10 Dec 2006 14:41:08 -0800, "redbrickhat"
wrote:

I recently opened up an old electrical box with a weak ground. To fix
the ground problem I wanted to connect a ground wire to a green
grounding screw into the box.

However, the old box doesn't have any holes for 8-32 sized screws, but
only for the larger holes (for mounting?).

Questions:

A) Is there any reason why I cannot screw the grounding wire into one
of the larger holes in the box?

B) What size screws fit the larger holes?

C) Would any normal screw metal type work?


Thank you.


IMHO:

I'm not there, so I can only tell you what I've done. I've used
ground clips where I could not use a secure ground screw. A quick
search in google for "Solid Conductor Grounding Clips" should help. I
believe they are for sale at your local lowes and home depot. Check
and follow directions.

later,

tom @ www.Consolidated-Loans.info

On Mon, 11 Dec 2006 01:46:02 GMT, (Doug Miller)
wrote:

Code requires that the screw holding the grounding wire may not be used for
any other purpose. So if the hole you're proposing to use is already in use
for mounting the box, or attaching a cable clamp, then the answer is no.
Otherwise, yes.

This always gets me. Lets say I always mount a box to a stud or joist
with 2 sheet metal screws. So I put in my two mounting sheet metal
type screws, but then add a 3rd sheet metal screw with a small washer
on the end to become the ground. Now this is actually only intended to
be a ground, but it is also going into the wood, thus holding the box
more securely. I didnt need a 3rd screw for holding the box, it just
happens to also go into the stud. I always wondered how the code
would view that????

Generally I always use the green screws made for that purpose, but
sometimes on old work using the sheet metal screw is the only option
without ripping the house apart. You really cant tap threads in the
box with wood behind it.

In article , wrote:
On Mon, 11 Dec 2006 01:46:02 GMT, (Doug Miller)
wrote:

Code requires that the screw holding the grounding wire may not be used for
any other purpose. So if the hole you're proposing to use is already in use
for mounting the box, or attaching a cable clamp, then the answer is no.
Otherwise, yes.

This always gets me. Lets say I always mount a box to a stud or joist
with 2 sheet metal screws. So I put in my two mounting sheet metal
type screws, but then add a 3rd sheet metal screw with a small washer
on the end to become the ground. Now this is actually only intended to
be a ground, but it is also going into the wood, thus holding the box
more securely. I didnt need a 3rd screw for holding the box, it just
happens to also go into the stud. I always wondered how the code
would view that????

Code would view that as a violation -- mostly because it's not making secure
contact with the box. There's a *reason* they supply boxes with holes that are
tapped for machine screws, you know...

Generally I always use the green screws made for that purpose, but
sometimes on old work using the sheet metal screw is the only option
without ripping the house apart.

What's stopping you from using a grounding clip? That's Code-compliant.

You really cant tap threads in the box with wood behind it.

Sure you can. I've done it many times. Just drill your pilot hole into the
wood, too. Tap the metal, and you wind up tapping the wood behind it too. So
what?

What's stopping you from using a grounding clip? That's Code-compliant.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

On 2006-12-11, wrote:

Generally I always use the green screws made for that purpose, but
sometimes on old work using the sheet metal screw is the only option
without ripping the house apart. You really cant tap threads in the
box with wood behind it.

can't drill and tap the back of the box?

wood's not going to stop a drill or a tap.

I wonder if self-drilling screws are acceptable, they're certainly
convenient.


--

Bye.
Jasen

"jasen" wrote in message
...

I wonder if self-drilling screws are acceptable, they're certainly
convenient.

I'm pretty sure they won't pass code - or the local inspector.

In article jUJfh.61030$YV4.46574@edtnps89, "Homer J Simpson" wrote:

"jasen" wrote in message
...

I wonder if self-drilling screws are acceptable, they're certainly
convenient.

I'm pretty sure they won't pass code - or the local inspector.

And why would that be? Got a Code cite for that?

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Doug Miller wrote:
x
In article jUJfh.61030$YV4.46574@edtnps89, "Homer J Simpson" wrote:

"jasen" wrote in message
...

I wonder if self-drilling screws are acceptable, they're certainly
convenient.

I'm pretty sure they won't pass code - or the local inspector.

And why would that be? Got a Code cite for that?

(2002) NEC 250.8 Connection of Grounding and Bonding Equipment.
".......Sheet metal screws shall not be used to connect grounding
conductors to enclosures."

(2002) NEC 250.8 Connection of Grounding and Bonding Equipment.
".......Sheet metal screws shall not be used to connect grounding
conductors to enclosures."

But "they" make grounding screws that are "self-taping" but aren't sheet
metal screws.

Indeed, sheet metal screws will likely not penetrate the steel in a typical
J-box. But the true self-drilling/self-tapping screws will do the job.
When you finish you have a tapped hole and a screw that fits and even is
"green". You can removing the self-tapping/self-drilling screw, if your
wish, and replace it with a regular machine screw (green or not). I don't
see why you would want to unless you have lots of machine screws but only
one self-tapping screw.

OR you can get the proper sized drill and a tap (and a tap wrench). Either
way you end up with a machine screw ready tapped hole.

According to my electricial friendly, the screw doesn't really have to be
green.

John Gilmer wrote:

According to my electricial friend, the screw doesn't really have to be
green.


That depends on the local code. A lot of places will fail any ground
screw that isn't green.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida