Small single-point internal threading

[SweetJustice]

I'm interested in tooling up to do single-point thread cutting on my Taig mill, and thinking that an indexable insert system makes the most sense, but am a little bewildered by the variety available.

One of the projects that I have in mind is to make a new Tr12x1.5 lead nut for my garage-sale chinese 3-in-1 lathe.

Are there any insert systems that can thread a bore as small as 10mm?

[SumDumPhuckr]

I would go solid myself

[SweetJustice]

I would go solid myself

I've looked around a little, and can't find a solid trapezoidal threading bar. Would you suspect that I'd have to hand-grind one?

[Mcgyver]

smallest I've done was a 3/16 two start 20 tpi, just under 5mm. That's a coarse small thread for single pointing! It worked but was a nail biter. Easiest way to tool for it is make it from drill rod and heat treat. You can turn the tiny 60 part as a profile then file/mill away what you don't need and file relief. If you've not made a cutting tool before, its much easier than it sounds