Threaded Tapers

I saw something like that, on the base of a camera, back in the film days. The threaded taper would atach the camera to a tripod. Other than that, I havn't seen such.

Christopher A. Young Learn more about Jesus

I've seen pictures of threaded tapers being machined on lathes and was wondering what the hell use they are? I mean, since the diameter of the threaded section is constantly varying, what can it possibly be screwed into? I cannot imagine any nut or internal thread that would accommodate such a piece of work.

Kindly disabuse me of my ignorance if you can, thanks.

P.

Pipe threads are tapered... It makes it more likely to seal when tight.

Please elaborate further. Pipe taps are tapered, and spring winding mandrels could be mistaken for taps.

jsw

No, it's not a pipe thread; very much steeper taper than a pipe thread...

BTW, is there a FAQ for this group?

Pipe perhaps.

Oil drilling pipe tool joints are also taper threaded. Cheers, John B.

The picture in the SB book is just an illustration. Exaggerated to make the setup clear. If you need a to see something modern, threaded with that much taper look at a tapered buffing spindle.

Paul K. Dickman

(Unfortunately, I probably can't help you but I'm curious, just the same.)

-- It takes as much energy to wish as to plan. --Eleanor Roosevelt

No one's mentioned wood screws yet, which are tapered along their length, or sheet metal screws, which are tapered at the nose.

Aren't taps tapered?

Spring winding mandrels -- I never thought of that.

I once ran a job on a CNC turning center for a threaded taper to make self tapping plugs for leaks in oil pipelines. The plugs were cut from hex stock and then hardened.

The leak was drilled out to one of several standard sizes, the right size plug twisted in, then welded in place.

These were much more tapered than standard pipe threads.

David

I suspect that drawing exaggerates the length to make the taper more evident than it would be on a real pipe tap.

I haven't seen any threaded tapers for tripod-attaching, just 1/4-20 or 3/8-16 straight threads, but mechanical remote shutter releases often have a tapered thread, as clearly seen in following photo.

Modern taps aren't really tapered, the threads are just on a tapered shaft (the top of the crest is ground off of the leading teeth, so cutting is progressive and not done all with the first tooth). But, old-timey taps WERE tapered, so you could get any tightness of nut you wanted.

This was important when bolts were made with threading-plate type dies (with poor diameter control) on forged rods (again, with poor diameter control).

Another tapered-screw application is seen on the pilot of auger-type wood boring bits. Yet another, is sometimes seen on citrus juicers.

Which reminds me of the puree-ing attachment on our Kitchen-aid mixer, which is a long tapered screw into a conical screen.

From a mechanical standpoint, a steeply tapered thread is capable of releasing upon a relatively few turns.

"Tim Wescott" wrote

The threads aren't (except for pipe). The taper is a separate grind that creates the cutting edges. Run a nut onto one and examine the free play.

jsw

I'll start writing it.

Christopher A. Young Learn more about Jesus

Yes, and still have the strength of something with many threads engaged. This is why it is used on drill pipe and also cable releases for camera shutters.

To answer the OP's second question, the female thread is also tapered.