self tapping screws

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peter said:
Don,
"What about using a nut and bolt/screw? Wouldn't this be OK?"

That's normally what I use if the side of the box is exposed to allow installation of the nut.
It's easier to drill a clearance hole and install a 10-32 (or 24) screw and nut than tap a hole.
I go to a 1/4" bolt and nut on larger (for me) lugs.
steve
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rasmithircgov said:
I agree there not aloud to be used.
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What's not allowed? Bolt & nut, sheet metal screw, tek screw, self-tapping 10-32 green ground screw, 8-32 screw?
 
hillbilly said:
peter said:
Don,
"What about using a nut and bolt/screw? Wouldn't this be OK?"
Click to expand...
That's normally what I use if the side of the box is exposed to allow installation of the nut.
It's easier to drill a clearance hole and install a 10-32 (or 24) screw and nut than tap a hole.
I go to a 1/4" bolt and nut on larger (for me) lugs.
steve
Click to expand...
If you have the clearance for a drill and bit, then you should have the clearance for a tap.



In case anyone doesn't know this already....you can tap a hole from OUTSIDE the box, then insert your screw from INSIDE the box ;)
 
I too have never been a fan of the ground clips. As with many other parts that depend on spring tension, the can get weak and ultimately loose with time. I agree that a tapped hole with a machine thread in it is probably the best way to insure a solid tight connection, however, I also feel that in many cases a self tapper or sheet metal screw can also be adequately tightened firmly to provide excellent continuity, although the code obviously disagrees. Isn't the purpose of the the threads to insure a solid tightening means that won't strip? The actual bond between the wire and the enclosure comes from direct contact, not continuity through the threads.
 
1) Did anyone notice this thread started July, 2003?:grin:
2) I like the new (at least to me) Greenlee drill bit/tap combo? LOVE them! one shot, no problem, plus they are only about 2 or 3 inches long.
 
JohnJ0906 said:
1) Did anyone notice this thread started July, 2003?:grin:
2) I like the new (at least to me) Greenlee drill bit/tap combo? LOVE them! one shot, no problem, plus they are only about 2 or 3 inches long.
Click to expand...


Bought those about a month ago, tried them out last weekend changing my heater core when a bolt broke and replaced w/ a 1/4- 20. Well worth the cash.
 
JohnJ0906 said:
2) I like the new (at least to me) Greenlee drill bit/tap combo? LOVE them! one shot, no problem, plus they are only about 2 or 3 inches long.
Click to expand...

Daddy, Daddy, can I buy me one for my birthday!?!
 
John, those bits have been around for twenty years. Maybe new for greenlee. I think Chicago made them.
 
pierre said:
Bill
I am 'thinking outloud' here, not questioning you.
250.126 mandates 'Device Terminals'. I do not see (that doesn't mean it does not exist) where it mandates 'box termination' screw color and type other than stating, sheetmetal screws cannot be used.
In retrofit work (there is plenty in NY, as I am sure you know), would a tek screw not be better than a groundclip for bonding an EGC to the 'old' box that does not have a 10/32 tapped hole? In testing and manufacturing of the groundclips, did they design for the thickness of new and old boxes or just new boxes? It seems every time I try to install the clips on old boxes they deform or break.

Pierre
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Greenlee makes a very nice tap/drill bit set. It looks likea drill bitfor the first 1/4 inch, then there is a thread tapping section. They are perfect for old work boxes.
 
The fact that we can use a next to useless grounding clip and not a self drilling screw is silly. Having screwed many self-drilling screws into metal boxes I can say that the connection is extremely tight. Far tighter than a grounding clip. If fact sometimes the screw head will shear off. If the connection were poor the screw should strip long before the head breaks. IMO a finer thread self drilling screw should be permitted for the connection of EGC to a metal box. The Caddy wafer head SMS8 screws would be perfect for this application.

http://www.erico.com/products/CADDYcfcWaferHead.asp
 
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