ring taps

Would this be what you're describing?

Don't know about the paint, but it sounds like you are looking for "serial" taps. Try looking for those, instead of "ring" taps.

John Martin

That sounds like the European system for marking the taps which we call:

Starting Plug Bottoming

with the starting tap having a long taper to make it easier to start on axis, and if you only need to tap something fairly thin that is sufficient.

The "plug" tap is the general purpose tap, used for most tasks.

The bottoming tap is used only when you need threads down to very near the bottom of a blind hole.

Enjoy, DoN.

Not quite the same thing, Don. I have a set of the taps that stevertoo is talking about that I got from Hare & Forbes here in Melbourne (Aus). They're basically full depth taps that have the teeth cut down parallel along the full length instead of being tapered.

So if you imagine a bottoming tap with 2/3 of the teeth ground down, you've got the starting tap. The second tap has 1/3 of the teeth ground down and the finishing tap has full depth teeth.

Advantages - they run straight in deep holes and the cutting force is reduced compared to normal taper taps.

Tony

--This sounds more like the taps that come with the "-1" or "+1" on 'em to indicate tapping shallower or deeper thread for certain applications.

Interesting -- and I think that I would like to have them for hand tapping. But for powered tapping, give me a spiral-point "gun" tap any day. :-)

Thanks, DoN.