RE: [CAD_CAM_EDM_DRO] Re: cutting threads on lathe

[...]

>
> Here's a little thread milling trivia...when you buy carbide thread
> milling inserts why do they have different inserts for internal
> threads and for external threads when the pitch is the same for both?
>
> Doug
>

My guess would be that since an internal threading insert needs a lot
of front relief, external inserts trade lifetime for similarity. That
is, an external insert can be made sturdier and have a much longer
operating life.

Another possibility is that they're NOT the same - crests and troughs
are allowed to vary from the theoretical thread shape.

Just guesses...

John Haddy
Sydney, Australia