09 April 2020

LEGO® Reverse-Engineering Challenge: Days 2-5

Posted by Admin
On the weekend we mentioned Ryan Howerter is running an advanced daily building challenge and showed you the first one. They appear on their Instagram at 11am Mountain Time every day but we know not everyone uses Instagram, so we've started publishing them on New Elementary's Twitter and now here are a bunch of them for those of you who are yet to catch up! We will try to keep this up but if not, there's always Ryan's Instagram!

Welcome back to the Reverse-Engineering Challenge, or REC for short. Simply look at these small LEGO builds, and try to figure out how they are built. Always assume the hidden side is identical. The colours are irrelevant. No rubber bands and no flex tubing allowed! It's not a contest, there are no prizes – think of it more like a daily crossword puzzle. Solve as many as you like, at your own pace. Solutions are posted every Sunday at https://linktr.ee/rhowerter.

REC5 by Ryan Howerter

REC4 by Sandro Tagliaferri

Special rule for this one: no Brick, Modified 1 x 1 with Studs on 4 Sides (4733) allowed! That's the Dalek Brick/Travis Brick.

REC3 by Ryan Howerter

REC2 by Ryan Howerter

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  1. Train of Thought LEGO Brick Creations9 Apr 2020, 19:20:00

    I think I've got it for the 1st three! These are super fun!
    Here's my guesses: https://flic.kr/p/2iNCciF

    1. So glad you're enjoying! You can compare to the 'official' solutions on Sunday!

    2. Train of Thought LEGO Brick Creations10 Apr 2020, 02:28:00

      Thanks! Will do! These techniques are so interesting to discover, they may prove useful for future builds.

    3. Shoot. I tried a similar solution for REC2, but with a different element that put the studs in the wrong place.

      Your REC3 solution uses some of the same elements as mine. I just realized my "sturdy" solution leaves some tiny gaps that aren't visible in the depicted model, so that's out. The more fragile solutions are valid, but unlikely to be the one used for the sample model.

      And I had the same idea for REC5, but apparently did it very differently.

  2. I bumped into a legitimate solution to REC2 before I had a chance to figure out one of my own.

    I lined up REC3 in MLCad, and all I can tell is that you need some sort of goofy SNOT technique that I'm not aware of, because nothing lines up cleanly on the inside.

    I found a few solutions to REC4, all based around the same type of part, but some of them are very fragile and hard to line up. The best solution looks like it belongs in a museum.

    And I've got a solution for REC5, but it helps that I recently did some similar work on a vignette base. This one is a little tricky because you have to be careful about what colors you use. Pick the wrong one, and you'll reveal the secret.