Mystery hole in drill bit

[lugnut]

I was cleaning up my 12" X 3/8 Irwin drill bit after drilling a deep hole in a Maple stump, when I noticed a 1/16th diameter hole midway up the bitt through the web. Does anyone know why the hole is there? I have never seen such before.

[lugnut]

And I also don't know why the second photo is there????

[Doozer]

For fishing wire.
A useful addition to a bell hanger's drill.

-D

[A.K. Boomer]

It's for free drilling by hand --- it's a strategic failpoint where the drill will snap off so as to not "spoil the work" as you will usually not be drilling that deep and can react in time, actually came about when working with mahogany and teak as it's a little pricey to have a "joe fudded up moment" then metal workers started using the practice about the time Dooze started using machinery...

[lugnut]

Thanks Doozer, I googled bell hangers drill and found this: "Bell-hanger drill bits are long bits that make holes through walls, studs, flooring, and other surfaces so wires can be pulled through these surfaces for hooking up televisions, telephones, alarm systems, computer networks, and other equipment."
Proves your never too old to learn something new

[A.K. Boomer]

Well so much for creativity lol (sheepish grin)

[Dan Dubeau]

That must be the drill bit from the old joke about "the yanks made a drill bit so small they sent it to the Germans to brag and the Germans drilled a hole through it" Or however it goes. Clearly we now see one side was exaggerating a little .

[A.K. Boomer]

I guess after feeding the wire through you would have another guy at on the other side pulling the wire tight as you put the drill in reverse slow mo --- that would keep it inside the flutes and keep it from getting severed on the way back out the other side....

Hey - if it's for pulling wire back through then why would you not have the hole more towards the end of the bit ?

[lugnut]

A.K. Boomer, when I looked up information about the bits they showed 12" (like mine) 18" and 24" long.. I guess you would need a whole set if you was in that sort of business .. I don't even know where I got mine. I buy tools all the time at yard sales, must have been something I just couldn't go home without. I have a lot of long drill bits from 3/16 to 5/8" and this one was the only one with a hole in it.

[A.K. Boomer]

I would think it to be an electricians norm but never seen one at my bro's shop,, maybe they just drilled and then started relying on sticking a fish tape through - at least that's all I can remember when helping and giving a hand...

[mickeyf]

And here I was going to suggest you check your tool box for Drill Termites...

[JoeLee]

It's for free drilling by hand --- it's a strategic failpoint where the drill will snap off so as to not "spoil the work" as you will usually not be drilling that deep and can react in time, actually came about when working with mahogany and teak as it's a little pricey to have a "joe fudded up moment" then metal workers started using the practice about the time Dooze started using machinery...

The hole could make it fail prematurely.

JL.....

[Jim Stewart]

I used to use those (occasionally pulled wire for the phone company). You drill through your hollow wall or whatever, then run one strand of your CAT5 wire through the hole, then pull the wire through the hole when you withdraw the bit.

-js

[A.K. Boomer]

Well I guess were not seeing Lug's full pic on it - maybe it's way longer and im just assuming it's half way up the bit thinking it's a regular sized bit... ?

[Jim Stewart]

Well I guess were not seeing Lug's full pic on it - maybe it's way longer and im just assuming it's half way up the bit thinking it's a regular sized bit... ?

The drills I used were 1/4", 18" long.

-js