Quote Originally Posted by Waterlogged View Post

Bottomless?

Sorry, couldn't help myself.

It seems it's been a very long time since you were on the floor of a shop. The styles of taps available are Bottoming, Plug, and Tapered. With a BSPP or NPSM, the only style tap available is a bottoming as there can't be any taper otherwise it's not a BSPP or NPSM.
Ok, it's a tap for threading holes that are "Bottomless" you know what I meant...lol...

Just because I worked in a shop didn't mean I knew the proper terminology. I did know what each was used for though.

For tapered I mean the taps that are cut tapered, not the actul threading tapered. All of my regular taps are cut at a taper for a good 1/3 the length of the tap except this one which tapers to full threads in the first 3 or so threads.

No problem when tapping on my mill or the drill press, but that would be less than fun tapping by hand without something to hold it plumb.