In late August, Kim Thomsen from the LEGO CEE Community Support team contacted myself and the Eurobricks team with a challenge. They are impressed with the database of alternate build MOCs that Rebrickable has accumulated and wanted to see what the community could come up with under some quite restricted conditions. These conditions just so happened to be similar to those forced on internal LEGO designers :)

Create an alternate build from a single City themed set:

  1. City themed alt build
  2. Designed in LDD (quite a challenge for noobs!)
  3. Buildable in real like (to ensure it is structurally stable)
  4. Target audience of 7-10 year olds

The requirement to use LDD was quite purposeful. Everyone who has used it knows that it is quite restrictive with the type of joins you can use - basically only rather simple designs are possible. Which is exactly what LEGO are looking for to target 7-10 year olds.

What was a little different to the normal alt build submissions on Rebrickable is that the MOC could not use any spare parts, only the parts from the printed inventory. I guess an admission that the spare parts can not be guaranteed, or maybe just leaving room for lost parts :)

A number of Rebrickable and Eurobricks MOC designers were picked at short notice (based on their past submissions/experience with LDD and alt builds), and each received a random City 2014 themed set. They had less than one month (depending on delivery timeframes which were quite painful in some cases) to design, build, photograph, render, and submit their entries.

At this time, not all of them have been submitted as MOCs to Rebrickable but they will come in due course.

The list of MOCs on Rebrickable.

The list of MOCs on Eurobricks.

A big thank you to Kim, if you are reading this, for thinking up this challenge and including Rebrickable!

Just a few samples...


  • 5 years, 4 months ago ouroboros Level 7
    According to the manual, there is a button called "filter bricks by LEGO set," but clicking on it doesn't do anything. There is an option for "Hero Factory," but that's it. And, according to the manual, this "Filter bricks by LEGO set," does exactly what I am asking for here...except that it doesn't. Do you have to somehow manually load the sets into the program or something else I am missing?
    • 5 years, 4 months ago JKBrickworks Level 21 MOC Designer
      See my reply to your previous comment...
  • 5 years, 4 months ago ouroboros Level 7
    This is related to a question I have posed on other sites like the Lego Facebook page and hit a dead end. Perhaps you have a better answer: Regarding LDD and full Lego sets, why is there not an option to restrict the parts available to build with in LDD to a certain set or list of sets? In other words, similar to what Rebrickable.com does, where you can enter sets you own so it tells you what else you can build based on the parts in your inventory, why is there not a similar option in LDD to build a set in the program and while you build it? The program could tick off the parts you have used in an internal database so that when you have used up the number of parts you own based on the sets you own, it somehow highlights that part red or tells you you have run out of that specific part so that you can know when you have run out of a given part and don't use more parts than you own for a given design. That seems like something the Rebrickable community and the Lego community as a whole would want. But it seems like an option that is devoid of even being considered for LDD. I realize many people order specific parts for their collection. But what about the rest of us who just buy complete sets and expect to be able to build other things with those pieces? At just under 30,000 parts now, it has become troublesome to keep track of the parts I own, without some sort of database. Hence, Rebrickable. There should be some sort of option in LDD for the same thing.
    • 5 years, 4 months ago dulsi Level 12 MOC Designer
      LDD does have the ability to use an lxf file to restrict what bricks/colors/quantities you can use. I don't remember what you need to do to use it. I used it when initially building my Man-Bat's Rocket Blast. It's useful if you have one set you want to build an alternate from and can find the lxf file online. Inputing multiple sets could be done but would take some work.
      • 5 years, 4 months ago ouroboros Level 7
        Interesting. Can you elaborate a bit? What is an lxf file, and how does it restrict the usable list of bricks? Can multiple sets be combined into one file?
        • 5 years, 4 months ago dulsi Level 12 MOC Designer
          See JKBrickworks reply. You could copy and paste multiple sets together in LDD I believe. Not sure if LDD has some limits. Sometimes the lxf files people make are missing a piece that isn't in LDD. The Man-Bat set had that problem.
    • 5 years, 4 months ago JKBrickworks Level 21 MOC Designer
      You can do this by creating a custom palette. How to do this is documented on Eurobricks.

      You can read this thread here: <a href="http://www.eurobricks.com/forum/index.php?showtopic=78072">http://www.eurobricks.com/forum/index.php?showtopic=78072</a>;

      For building an alternate model it is even easier. If you can find the lxf file in eurobrick's official set model repository you only need to do Step 4 and drop the lxf file in the user palettes folder.

      Once that's done a button should appear on the bottom of the palette in LDD that allows you to switch between available bricks.

      You can find lxf files for LEGO sets in this forum on Eurobricks: <a href="http://www.eurobricks.com/forum/index.php?showtopic=41226">http://www.eurobricks.com/forum/index.php?showtopic=41226</a>;

      It would be pretty sweet if Rebrickable had links to these lxf files for those sets that have them.
  • 5 years, 4 months ago Meiko Level 6
    This was a really cool challenge. Awesome idea of Kim's and congratulations to Rebrickable for being noticed and chosen by LEGO for this! What a great way LEGO is engaging in the fan community. :)
  • 5 years, 4 months ago jantjeuh Level 28 PRO
    Hah, I was wondering where all these alternate MOCs were coming from all of a sudden :D Now I know.
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