Fyi, flame polishing only works on SOME plastics: acrylic (plexiglass), and PLA (poly lactic acid) are two I'm sure about. It's a function of melting temperature, surface tension, and thermal conductivity.
I know for sure it doesn't work on polycarbonate (lexan) and ABS (acylonytrile butatiene styrene). Past that YMMV.
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