What drill bit is this?

[sundaybighouse]

Hi guys, I've inherited a few tools and I was wondering if you could tell me what this drill bit is called and what it is for?

Thanks for your help.

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[merlin50]

its a tap for taping threads

 

[Trazor]

Not really for use in a drill, you would use a tapping head or a tap wrench

 

[sundaybighouse]

Ah thanks merlin50 and trazor

Just checked out a video on how to use them.

I don't have the wrench part to use them, maybe I'll find it as I've got lots more to go through.

Thanks again.

 

[Burnerman]

Just for info / knowledge or maybe its because I'm an anorak but thats a taper tap, which is used to initially start the threaded hole. Ideally that should be followed by a second and finally a plug or bottoming tap which would be essential if the hole in the metal was blind.
All screw cutting taps like this one need the correct size of tapping drill before the thread will be formed correctly, and a suitable cutting lubricant is essential.....not to mention the technique!
Anyone remember the Zeus booklet for tapping sizes, and Trefolex cutting grease?
John

 

[sundaybighouse]

Thanks Burnerman.

 

[XtraRaptor]

Just for info / knowledge or maybe its because I'm an anorak but thats a taper tap, which is used to initially start the threaded hole. Ideally that should be followed by a second and finally a plug or bottoming tap which would be essential if the hole in the metal was blind.
All screw cutting taps like this one need the correct size of tapping drill before the thread will be formed correctly, and a suitable cutting lubricant is essential.....not to mention the technique!
Anyone remember the Zeus booklet for tapping sizes, and Trefolex cutting grease?
John

Mmmm. Trefolex..

 

[stuartturbo]

Anyone remember the Zeus booklet for tapping sizes, and Trefolex cutting grease?
John

Still have two and use them one was a hand me down from my Grandad and is older than me 1972 issue then i got a newer one lol

 

[wotan]

One of the most useful series of tap's and dies were the B.A series, unfortunately no longer a British standard, common sets usually were in the range 0 to 10 B.A
The numbers represented the number of taps used to successfully tap a deep hole in steel

Wotan