Tapping collets

[Agroshield]

My machine (toy) is rated for 20mm taps... I just need to get to 20mm DIN collet now somehow.

We might need to step back and take a wider view to gain some perspective. Proceeding on the basis of a single source of information, when the reliability of that source is not clear, might lead to false conclusions.

Survey the market of professional level tapping machines (in other words, exclude AliExpress from this survey). There are suppliers of this type of machine in Australia, USA, Europe and UK. Do any of them claim M20 capacity for a GT12-series?

You have looked for the collet. I have looked for the collet. Kram has looked for the collet. None of us has found the collet. The people who first popularised this style of machine do not list the collet. That suggests the collet does not exist. Hence, you may need to explore alternative options - either modify something that is available or make an adaptor.

I am quite sure there is not a single supplier of taps in the whole of Australia. At some point, it will be cheaper to throw all your M20 DIN taps in the bin and buy new ISO ones from an alternative supplier.

 

[Munkul]

GT12 collets are far too small to make them work with an M20 shank. Pressbrake1 has already stated this.

If you're desperate to tap M20 (and have the power to do so) then convert to GT24!