What tools do you use when planning and designing a new MOC? Pen and paper? Or there is something more advanced?

I had the insane idea to try LDD to design my MOC and it was a nightmare. Since my MOC uses sets from castle fantasy, there are maybe 3D models ready to use for LDraw or other kind of software suitable for this task?

EDIT: I will go into further details to explain my issues better.

This is the list of sets I want to place in my MOC:

Fantasy Era:

  • 7036 Dwarves' Mine
  • 7094 King's Castle Siege
  • 7079 Drawbridge Defense
  • 10193 Medieval Market Village
  • 7037 Tower Raid
  • 7029 Skeleton Ship Attack
  • 7048 Troll Warship
  • 7097 Trolls' Mountain Fortress
  • A lot of smaller sets like 5614 The Good Wizard that do not take space.


  • 6918 Blacksmith Attack
  • 7187 Escape from Dragon's Prison
  • 7188 King's Carriage Ambush
  • 7189 Mill Village Raid
  • 7946 King's Castle

I want to build a nice terrain where to place all those sets together. for example, a mountain where to place the Mine, and a hill to put the Blue Castle on top. The a river for the Drawbridge, a plain for the medieval village and the the mill, a coast for the harbor, a sea for the two ships, and another coast for the Troll fortress. I have yet to decide where to put the Red castle.

The whole MOC would require 10-14 big baseplates (my estimate). So planning the whole thing is very hard and I got lost with LDD very soon. To make things easier, it would help a lot if the software has the "size box" for the sets, so I have a way to understand how to place each set on the scene without having to build them from scratch, so I can concentrate on the terrain.

I have no clue on how to go forward on this, to design all the terrain and then get the component list (and it's cost) to build everything.

  • 2
    Hi Terix, this question is probably not a great fit here on LEGO Answers as it's really only answerable with Opinions. As TheBrickBlogger points out if you post about the specific issues you're having we can give you some better answers. Commented Jul 30, 2014 at 18:49
  • I've added more details to narrow down my issue, hope it makes a better question.
    – Terix
    Commented Jul 31, 2014 at 15:13

4 Answers 4


Design stage

  1. decide roughly where everything should go

  2. use various boxes to place them at the right position and height

  3. build the bits in the middle once you are happy with the layout

  4. if you don't mind cheating and are good with a ruler, you could build a multi-level base-plate out of wood and just build the very top level of ground.

Buying pieces

(Duplo is relatively cheap and builds big to lay down hills/mountains, use Lego bricks on top to provide a building surface.)

Find a lego store that you can get to easily and often.

The Pick-a-Brick wall will often have useful grass / slope / tile / transparent pieces that can make large and cheap filling areas (pour lots of clear blue 1x1 round plates into a tray for water).

If there is a really useful piece on the PaB wall you can ask for a box full of pieces, (which I believe is known as a K2), this is probably the cheapest way to buy 1000s of bricks at a time, (if they have a box available).

inventories for local Pick a brick walls: http://wallofbricks.com/

  • There is any way to know all the sizes of built sets either in cm or knobs? I have all the sets stored away because lack of space and would be easier to avoid opening everything to check sizes.
    – Terix
    Commented Jul 31, 2014 at 22:08
  • 1
    Official Lego website has all instructions for download as PDF, Brickset.com has a database of most sets that can be used to find pictures and instructions from other sites.
    – Windfire
    Commented Jul 31, 2014 at 22:25

Some of the more popular programs used when designing MOCs are:

There are some other ones available but those three seem to be most preferred editors. They all have quite similar set of features but their user interfaces are very different. I encourage you to try each of them out. If you wish to find most extensible software, MLCAD seems to be rather old and stable platform to build upon.

I myself use pen & paper for concepts and ideas and LEGO Digital Designer for designing.


I'm not sure why are you saying that using LDD to design your MOC was an "insane idea" that turned into an "obvious nightmare". LDD is meant exactly for that; designing MOCs. You don't mention what issue you ran into, but you should be able to build any kind of castle in LDD just fine. If you specify what problems you encountered others could probably help you with solving them. Although LDD was originally intended for children to be able to design their own MOCs and order them directly from LEGO (a feature that has been discontinued), it is very powerful and you can design pretty much anything.

I myself use a combination of planning on paper, real LEGO bricks, and LDD to design MOCs. Paper to get the initial concept, real bricks to work out scale and some details, and LDD to finish the MOC and get the bill of materials so I can order the pieces I don't have from BrickLink.

  • 1
    I looked at your updates to the question. Yes, that is going to be a challenge because unless you virtually build all those sets it is going to be hard to work around them in LDD. May I ask why you want to create this project virtually? Usually for very large projects like this people just build them in real life. Landscaping is not that difficult to tie buildings together; some grass, some trees, a river, a couple of roads... you don't really need LDD for any of that. Commented Aug 1, 2014 at 0:59
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    As far as your question in regards to each of those sets, you should be able to figure out the size by looking at the picture of each set and counting the studs of the foundation. Commented Aug 1, 2014 at 1:02
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    Here is a link to an article I wrote some time back about building a Medieval Village, including landscaping. You might find it helpful: thebrickblogger.com/2012/08/… Commented Aug 1, 2014 at 1:07
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    Since your project is going to be very large, I would suggest that you work with contstruction paper. You can draw out the outlines of the castles and other various buildings, and you can also plan out the baseplates. This should help you build the furniture that will hold it all. Commented Aug 2, 2014 at 15:49
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    Also, I might suggest that you may want to make that furniture modular. In otherwords, instead of making one large table, make i.e. 4 smaller ones that can be configured in different ways. This way you can always expand our layout, or make it smaller, or configure it differenently, depending on your needs. Commented Aug 2, 2014 at 15:51

I know this is an older question but, for anyone else who might be looking for a good way to plan/design/refine a MOC idea, I wanted to throw in my 2¢. For the past week or so I've been working on refining my own MOC idea using Mecabricks. It's taken me a little while to get familiarized with the toolset available and there are probably some features I haven't even looked into yet, but it's a pretty great, online LEGO CAD (computer-aided design) tool for putting together MOC's. If you just want to "jump in" and start building, their Workshop is accessible without any signup, although to save your designs you'll need to register (free) an account.

I've not tried their import functionality, so I can't speak to that at this time. I'm not sure how it works or if it would be a way to bring in the information for existing sets. I couldn't say if there are any bricks "missing" from their available list but you can use pretty much any color, including transparent, metallic, etc. It does not (currently) offer the feature for producing instructions, although that appears to be in the works. It does, however, offer a way to export the parts list when you're done to a CSV file or an XML file that can be used on BrickLink to add the parts used in your MOC to a wanted list.

Just for reference, I hadn't used this site until this week, and I've already been able to use it to create several variations of a pretty simple MOC idea I had (my designs use bricks that apparently aren't available in the colors I've chosen, but this has at least given me an idea of the direction I want to take it).

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