Summary

Openscad version now available, neat and works as a real threadcutter on a lathe. ,be carefull of large numbers in openscad though if youre trying to cut profiles with zeros that are supposed tobe zeros but are not and are just very very large numbers. eg, using sin cos tan to draw a curve can result in what is zero/1 but is actually not.
Now with outfeed. Whatever math I did UMM I think 0.75 is 75% of the turns.

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Pair of STL files for generation of extendable leadscrew that you can make to any length, simply by printing more of them on a 3d printer.

Its round thread because that stuff works better with inaccuracies.

Get some 6mm threaded rod to tie the printed pieces together to make a long length.

The nut is oversized to 1mm diameter freeplay, and 0.1 mm freeplay in the thread radius.

Ideal for lathe or mill projects where you just don't wanna pay.

Upload the results of an openscad version - 20minutes to render. Not happy... Understandable - 6mb? what the hell is in their?