Secret knock-detecting mechanical iris project

Over at the Submitterator, BFarn tells of his excellent maker-meld of "Chris Schaie's beautiful Mechanical Iris, Steve Hoefer's Secret Knock detecting Arduino code, and an engraving made with my scratch-built CNC-Router to make the entrance to my garage/workshop/lab a bit more special."

BFarn's project page

Mechanical Iris on the Boing Boing Bazaar



  1. That’s absolutely gorgeous, and I hope someone will tell me what that Latin phrase is.

    But *UUUUUGGGGHHHH* did the password really have to be “Shave and a Haircut?” So tired of it at this point.

    1. Given the gorgeous design and brilliant engineering, I’m going to give the creator the credit they deserve and assume that this particular knock was only for demonstration purposes. After all, why give away the password to your garage on YouTube? ;-)

    2. I’m sure “shave and a haircut” was only for demonstration purposes. It IS programmable.

      I love this concept! Well done.

  2. Beautiful! As for what it says, shame on you heathens. Did you not read your Bibles in the Latin?

    Petite, et dabitur vobis : quærite, et invenietis : pulsate, et aperietur vobis. (Matthew 7:7)

    Which translates as…

    Ask, and it shall be given you; seek, and you shall find: knock, and it shall be opened to you. (King James Bible)

    1. Stoned guy again: this comment on this post is exactly why I love boingboing. I somehow knew that within 10 comments someone would have posted a translation, and also that the lovely verse would add even more to the wonderful idea above.
      Also, that it was done in just 6 posts is awesome. Thank you for the great translation!

      1. Glad to be of service. It should be noted that you can find mention of weed in the Good book y’know. Well, if you believe every stoned hippie Christian I’ve ever met anyway.

        Et suscitabo eis germen nominatum et non erunt ultra inminuti fame in terra neque portabunt amplius obprobria gentium (Ezekiel 34:29)

        Translated as…

        And I will raise up for them a bud (plant) of renown: and they shall be no more consumed with famine in the land, neither shall they bear any more the reproach of the Gentiles. (King James Bible)

        1. they shall be no more consumed with famine in the land

          Doesn’t that imply that they won’t get the munchies?

          1. Or perhaps it refers to the appetite stimulating properties of weed for those suffering from serious illnesses?

            I’m a former seminarian who has never touched the stuff, but delighted in making those who do smile and say “Wow. God had a PLAN man”

  3. It’s true – Shave and a haircut is for demonstration purposes only. The real secret knock is the opening bars from the Legend of Zelda.

    But holy…. WOW, I’m so glad you guys like it! I really didn’t expect this to get picked up so fast. I hope it inspires more people to do more fun stuff.

    Thanks BB,

  4. David, I may be extremely high at the moment, but don’t hold it against me when I say that is a beautiful synthesis and it was executed with style. Right on, brother!

    1. That’s exactly what I was thinking. If I found a garage door like that I’d probably start groping for the space bar. Beautiful.

  5. The gear transmission should be different, so that you have to spin the handle a lot more (10 times round or more) to open the iris.

  6. I would like to echo the “Brilliant” comments. Our ‘maker’ family, which includes Steve of secret knock fame, is thinking of all sorts of applications and modifications…bwahhahahah. Thanks for your work!

  7. I must have misunderstood the description. I was expecting the Iris to be activated by the secret knock. More steampunk speak easy than MYST puzzle. This is cool too. Honest, I’m not disappointed at all. Maybe you could make guest visit 3 other locations and solve puzzles there in order to get parts of the knock code before they come in.

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