binney said:Does anyone make a self drilling ground screw? I've seen self tapping ground screws, but never a self drilling ground screw. I'm not talking a #10 self tapper, but something with a self drilling tip and 10-32 threads.
tom baker said:Those screws won't be allowed in the 2008 NEC, it will call for a machine screw with at least two threads in contact with the enclosure. (this is a change to 250.8)
I prefer the greenlee tap it, they are great.
Minuteman said:Zip in a #8 drill tip screw with a 5/16" head, back it out, zip in a self tapping 10-32 greenie screw. Done!
LarryFine said:Would you settle for the next best thing?
TOOL_5150 said:I bought a set of these, and they are great. But does anyone have any good ideas for tapping holes when the panelboard is allready installed, and you dont have much more than 1/4" - 1/2" of clearance behind the panel?
infinity said:A self tapping #10 greenie screw will go into a #8 hole?
This is true. Simply drilling a regular panel enclosure using a 10-32 tap will not provide enough threads to secure a ground or anything else.Pierre C Belarge said:I am stretching here...from somewhere in my memory...maybe someone else here can help.
Tapping a panel enclosure for the grounding screw is not permitted, one would need a bolt and nut or other effective means.
When a manufacturer taps a box, they actually put a "dimple" in the box creating a little more "meat" at the location so there is enough threading for the screw to catch. When we drill and tap there will not be enough threads.
Of course if I am wrong, it will be established before the end of the day.
Minuteman said:If you use a DeWalt 18volt impact driver like this, it will!
If you use a #10 screw to make the pilot hole, the greenie may be too loose. Self tapping greenies are tapered at the end and have cutting edges to cut the threads.
FWIW, There are two types of self tapping greenies. Both have the taper, but one has a large notch and the other has several lengthwise grooves. I prefer the ones with the notch.
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mcmaster carr even has green ones!DPW said:From the previous threads, I have not had any success finding a source of a 10/32 self drilling, self tapping machine screw.