A gent named Scott Smith posted on his blog and FB a few months ago about modifying the E3D V6 silicone sock to prevent it from grabbing the printed part and either pulling it off the bed or pulling the sock off the hot end. At the time I scoffed. I had 1000s of hours of printing with the sock on multiple printers without a single sock-related fail. That was with printing PLA, Nylon and ABS.
Late last year I started printing a lot more PETG - especially the Atomic Filaments PETG Carbon Fiber Extreme (my new go-to filament for mechanical things). Turns out my sock experience parallels Scott's – the sock grabs the print and little bits of the sock get torn from the opening. I've observed that PETG is much sticker than PLA and ABS and grabs the sock. This can result in a tear, small pieces of sock broken off, parts ripped from the print bed and even – gasp – spontaneous mag ball disassembly (SMBD).
Scott's simple modification has worked perfectly. He carefully removes the inner diameter around the nozzle opening as shown here:
Use a new X-acto knife blade to carefully cut out the disk. I now have 100s of hours of PETG printing without a single fail. The sock still does its primary job of insulating the heater. But the secondary task of minimizing filament stick (for PLA and ABS) is lost. But now I get to do this again: Polishing nozzles for improved layer quality.
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