• JR Knifemaker
    Afternoon all-
    Quick question: does etching in ferric chloride leave a food-safe finish? I’ve noticed that it leaves some oxide on food when using the knife, even after repeated use. Would vinegar+mustard be safer?
    Thanks all
  • Tom
    Ferric acid isn’t food safe.
    If you’re going for a forced patina then vinegar and mustard would work a treat.
    I think it was @Jeff Kushen that said he uses hot apple cider vinegar then Marerko’s coffee treat to finish.
  • Jeff Kushen
    Yep, It was me! ;-)
  • JR Knifemaker
    ah okay. That’s a bugger....! I won’t tell my wife she’ll accuse me of poisoning the family.
  • EbonbladeCustoms
    Follow up question, is ferric chloride then coffee food safe? I feel like the coffee etch would create a food safe coat over the FeCl
  • Tom
    I feel like the answer would be no, but I’m not 100% sure on that
  • Jeff Kushen
    Ferric chloride is NOT repeat NOT food safe! A simple method is as follows:
    Sand blade to the desired finish.
    put on fresh latex gloves
    Clean blade to remove all traces of oil, grit, etc.
    Heat apple cider vinegar to boiling... DO NOT DO THIS IN THE KITCHEN OR YOU WILL REGRET IT! DO NOT INHALE!
    Place blade in hot vinegar, pull out to check for even coverage. If not, sand and re-clean blade. if even, submerse again and let sit for at least 20 minutes for 1095, 30 minutes for O1. Experiment with times for your steel of choice.

    Remove and rinse in HOT water only. DO NOT use dish soap at this time!

    Dry thoroughly!

    Boil 2 quarts of water (this can be done in your kitchen if you wish.
    Once boiling, add ONE FULL CONTAINER of Nescafe Dark Roast Classico Instant Coffee (Walmart Great Value brand also works well, just get DARK ROAST). Mix well while maintaining boil.

    Insert blade into coffee mix. Check for even coverage. Let soak as long as you want. I have let a blade soak for 12 hours with no ill effects, and it looked GREAT!

    This coffee mixture can be reused for months, and I find 1 Gallon Glass Pickle jars work well for storing it. I re-heat it before etching the next knife, but I am told you do not need to do this.

    I hope this helps you! Let us know!
  • JR Knifemaker
    this is awesome thanks Jeff. I’m going to try the mustard/vinegar finish too that’s been mastered by @Swift Knives UK
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