Spiral point taps

[Pat of TN]

Can someone tell me about thread forming taps ??

I don't know much about them, but a fellow student at school does and I've learned a bit from him. Thread-forming taps (he refers to them as roll taps) require a larger tap drill than a conventional, cutting tap - a chart could be found on the internet - but they produce a cleaner thread with a superior surface finish to a cut tap, while also producing no chips - that means no chips in the bottom of the hole as with other taps (sans spiral-point).

They are also stronger, due to the complete lack of flutes.

That's all I know, and technically it's all secondhand or theory, as I've never actually used a forming tap. Wouldn't mind trying it.