What are the advantages and disadvantages of an all-metal hot end compared to one with a PTFE heat break?

  • Related to an issue I had in this question, where the PTFE tube feeding my filament to the metal tip of the extruder clogged and became discolored: what are the advantages and disadvantages of changing out my extruder (Mk10 on a FlashForge Creator X) for an all-metal solution like the one advertised here (by Micro-Swiss).

    I understand that the conversion would allow me to print higher-temperature materials (like nylon), but I'm also trying to figure out the trade-offs with regard to printing PLA/ABS parts.

    Following. I've been having a nightmare with the throat pipe. I didn't realise the PTFE was part of it, rather I guessed it was the cause of my blockage (I'd been printing in white). I've got some all metal ones on order now.

    "throat pipe" is chinglish. "Heat break" is the proper name.

    "heat break" or "thermal barrier tube" depending on the hardware's lineage.

  • JorgePerez

    JorgePerez Correct answer

    6 years ago

    This is a good question to make a comparison table. All-metal hotends Vs. PTFE liner hotends.

    All metal:

    • Works well for high (+250ºC) temperatures filaments like nylon or PC.

    • No need to replace the PTFE liner (pretty obvious).

    • Retraction performs worse.

    • Plastic can get stuck to the inner walls. This can lead to clogging, more likely when changing from ABS to PLA (higher temp plastic to lower temp plastic).

    PTFE liner hotend:

    • Limited working temperature. Above 250 PTFE will start to degrade.

    • PTFE tube needs to be replaced more or less often, depending on the use of your printer.

    • Retraction performs better.

    • Plastic is less likely to get stuck in inner wall (PTFE is very nonstick).

    • When using PTFE liner, the plastic is melted very close to the nozzle. Unlike other techniques, in FFF/FDM 3D printing this is more desirable. E.g. to avoid 'heat creep', for a better flow control and more accurate output dimension.

    Of course there are more points to compare. Please comment to add any other useful point.

    Also less heat creep.

    what is retraction performance?

    @user391339 I know this is an old question but for anyone who comes along with a similar question, I'll take a stab at an answer (anyone plz chime in if I'm wrong): retraction is when the extruder pulls the filament back. You don't want the filament too warm when it goes back, may stick to lining, etc, which is what the heat-break helps with. Bowden configs require extra tuning / calibration and will generally have a much higher retraction speed / distance. Retraction can happen for many reasons, notably when the nozzle needs to clear a gap, so it doesn't drag filament and cause stringing.

    The hot ends without PTFE in be bottom part and have PTFE with cooling fins in the upper one classify as PTFE lined?

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Content dated before 7/24/2021 11:53 AM