The Drill has Landed!

[MrFluffy]

I have a tapping head, but its because I have no quill on my milling machine, so if you turn the handle the wrong way starting or dont follow the tap entering properly, there is just this sickening crunch as it all disintergrates if you hold the tap in a collet or jacobs chuck too tight. The tapping head allows a floating action so when the tap bites and pulls in, you dont have to react instantly. A sensitive quill on a dp doesnt really have that issue. Reverse might be handy if your using straight flute taps still though, but your better off using machine taps if your getting into that level.
Until I got hold of the tapping head, I got by just starting them in the drill press winding it round by hand, then finishing the job with the part in a vice by hand. Moly grease is your friend. Or trefoil, or tap magic or whatever brand of moly based grease you want to use.

 

[MattF]

I use them for drilling out broken studs, As the stud normally comes out with the heat before you get close to the threads.

Ah. That makes sense. I normally just drill and use a left hand tap for that purpose. I've noticed that most of the time, the rotation of the drill will normally free the bolt/stud too, making extraction easier with the tap.

 

[the artfull-codger]

You can easily enough tap just by winding the tap in by hand. Once it's chucked, you have the alignment. Looked at the tapping heads several times myself, but never as yet found a convincing reason to bid on one. You'd have to be doing a lot of tapping to make their purchase a viable thought, even if they go fairly cheap.

On a tangent, what the hell are left hand drill bits used for?

they're used on multi-spindle drilling machines that have to drill holes close together on production runs as you can run them closer together with less internal gears than using more gears that would be further apart & as b.s. says why do people need reverse on a pillar drill for 99.5 % of the work??.