Tips on how to build large Rebrickable MOCs? (sorting of the pieces)

[HibiscusDrive]

The nice thing about building Lego sets as-is is that the pieces come in numbered bags, and you can spill them out and never be digging through too many to build away.

But when you download and build others' MOCs, whether you bought one or more large sets and the pieces from the next pieces needed could be ANYWHERE in the set, digging for the pieces is tedious. I've built a few downloaded MOCs that were up to 1400-ish pieces. I usually spill them onto a stackable Rubbermaid bin that has the edges, so when I dig for them, they don't fly off the bin. And I need to stay in the basement so I can access my own supply of pieces for my own modifications. 1400 pieces makes the top of the Rubbermaid bin really full, but manageable. I am about to embark on a 4400 piece build, which is obviously won't fit on top of the bin, and as you know, the next step's piece could be anywhere in the pile.

Do any of you have strategies for how you build these large sets?

[MAB]

I sort roughly by part type, then by colour. So all bricks are at one side. When getting the parts ready, I tend to have bricks bagged by colour and type and keep them in the bags. So if I need a blue 1x2, I just lean towards the bricks, reach to the blue area and pick up the 1x2 bag.

If it was much bigger, I might sort by type and brick ID (like my main parts collection) rather than type then colour, but that can take up way more space if you have huge numbers of part types.

[JesseNight]

I don't know better than not having numbered bags with pre-sorted stuff from my young Lego days. Back then, the bags were still sorted but in a different way. Bricks together, plates, small tiles and lights, Technic axles and bushes.
That's the same system I would still use when building a bigger project. Sort out the parts per type and color somewhat. Take your time sorting and make sure to have some space available, and a safe way to keep the small parts together. Don't see it as a chore, because the building experience after will be a lot easier.

[Stereo]

I usually go by category in small trays, with one tray being "rare parts" so that if a set had 500 plates in various colours, but only 1 blue 1x2, the blue one is in the rare parts tray.  For system builds it's usually plain plates (1x1 to 1x12), modified 1x anything plates, larger plates, bricks, and 'everything else'.  Though if it was very plate-heavy it'd split further into 1x1 to 1x3 and 1x4 to 1x12, and so on.

 

Sometimes I don't follow a MOC's colours exactly, and in that case I'll also sort by colour, so that it's easy to find the right substitutes.  Eg. if a set needed 100 1x4 yellow plates and I was using some brown ones, then I could see them in the yellow bin.

Edited December 5, 2025 by Stereo

[HibiscusDrive]

Thank you all for the advice. It all makes a lot of sense and will definitely make pulling 4400 pieces a LOT easier.