Stretch it yourself?
No, this is done after extrusion. The different types of nylon also
have different melting points. The process of "stretching", along
with some other information, is described here;
http://web.utk.edu/~mse/pages/Textil...n%20fibers.htm
It is more or less impossible to do any of these things in an amateur
workshop or similar. They are industrial processes requiring special
machinery and know how. I developed and built some electronic
monitoring equipment for some process lines, and learned quite a bit
about the processes while doing so.
Sorry, once again, I donīt have any specifics for fluorocarbons. I
only have some very general information on fishing lines.
Regards and tight lines!
Mike Connor