Chemical Compatibility of PETG and Antifreeze! MUST READ!

So @Eclsnowman was sharing pictures of his new beast of a CNC router on Twitter (maybe we could get him to share some here as well :wink: )

And he was worried about some cheap plastic fittings that might not hold up for his water cooled spindle when using antifreeze.

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So he called on the chemistry wizard yours truly :test_tube: :mage: :smiley:

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This is the thread of my answer.

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Here is the table of what the PDL number means (higher is better)

So long story short, most plastics, includging PETG, will most likely be compatible with glycol based antifreeze. PG based antifreeze may or may not be better then EG ones, but I have no reason to suspect it would be worse. No guarantees, but that’s the indication of the available information.

To be on the safe side I would do visual checks at least every 6 mo to verify there is no significant color change or part swelling.

Also sorry not sorry for the dramatic clickbait title. :wink:

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I can’t believe the magician revealed his tricks!

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Thank you for all the help by the way. And yes I plan on posting it here, I apologize sometimes I’m bad about doing quick Twitter posts from my phone versus sitting down and typing out something more long form for the forum. I need to get better about that. It really should probably be here first and then out on Twitter maybe draw in some eyeballs.

But I’ll admit I’m self-conscious about posting “work in process” stuff here, only because when I put it here it feels more finalized and formal like I need to have it better and figured out. I need to work on changing that mindset and use this more of a build log for posting. I take a lot of pride in what I post here, and I don’t want to be wrong or make mistakes, that feels more like Twitter is ephemeral nature. When it’s here it’s gospel :slight_smile:

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Heh, I’m not worried about posting gospel on the #monocle tag! :slight_smile:

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