You are one crafty guy!!!
Let that extrude in to a bucket of water to quench it, and roll it up on a spool - you'll be good to go. It would be a bit better if you could extrude a bit larger and draw it down to 1.75 mm, but it should work the way you are going here. I am wondering about using the method you show there to make a plastic molding "press"... Inject in to a cavity instead of to the "string" you are making, and then inject that cavity in to a mold. I am surprised how small all the DIY molding machines I see are, and it seems you are on the way to making a very affordable option with a larger shot size.
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