Diplodocus Brick MOC: Build a 4-Legged Giant
The short version: this Diplodocus MOC uses about 520 parts, measures 36 cm long when finished, and takes roughly 1.8 hours to build. The two things that make or break it are the slender S-shaped neck and the four-legged stance — the centre of gravity sits in the middle of the torso, all four legs share the load evenly, and the model stands firm and looks good from any angle. Full instructions are available on brickplan, so building from the plans is a zero-barrier job.
Step 1: Prepare and Sort the Parts
Start by sorting parts by colour and function: dark grey for the internal frame, light grey for the limbs, green for the body armour. Set aside two 24x8 baseplates as the torso foundation, plus eight hinge pieces and eight ball joints. Sorting takes about 10 minutes and will roughly halve your build time later on.
Step 2: Build the Torso and Spine
Connect three torso frame segments with hinge pieces to create a gently arched back curve. A Diplodocus torso is actually short — around 10 cm — so the real work here is shaping the spine's arc, which sets up the long neck and tail that follow. This step determines the whole animal's posture, so make sure both sides line up symmetrically.
Step 3: Form the Slender Long Neck
String 12 ball joints together into an S-shaped curve, run a flexible hose through the inside as support, and wrap the outside with 1x2 plates. The neck is about 14 cm long — nearly 40% of the total length — and it is the Diplodocus's most recognisable feature. Tighten each ball joint one notch so the neck does not droop.
Step 4: Build the Four-Legged Stance
Each leg uses 8 parts: a ball joint at the thigh and a foot piece at the shin. The key trick is to make the front legs slightly shorter and the rear legs slightly longer, tilting the body forward about 5 degrees to match the real animal's stance. The four contact points form a rectangle, and the centre of gravity sits in the middle of that rectangle — that is what keeps the model standing securely.
Step 5: Add the Long Tail and Finishing Details
Build the tail from hinge pieces in decreasing sizes so it narrows section by section, about 8 cm long, with the tip curling slightly upward. Finish with eyes and back-armour patterning, and keep the head small and conical so it contrasts with the massive body for a bit of charm. On a display shelf, it draws attention.
FAQ
Q: How do you build a Diplodocus MOC?
A: Sort the parts according to the plans first, then build the torso frame and work outward through the neck, the legs and finally the tail. The brickplan plans include a rotatable 3D view and a parts list for every step, so following along takes about 1.8 hours.
Q: Does it stand up securely?
A: Yes, very securely. The design keeps the centre of gravity in the middle of the torso, with the four leg contact points spread in a rectangle and the front legs shorter than the rear to create the forward-leaning posture. As long as the ball joints are seated as shown in the plans, it will not topple during normal display.
Q: How many parts do I need?
A: About 520 in total, the vast majority of them common basic bricks, plates and hinge pieces that most builders already have in their collections. If you are short of anything, you can fill the gaps by part number through the brickplan community — no rare pieces required.
Q: Is it suitable for beginners?
A: Yes. There are no complicated mechanical linkages; the only real challenge is the S-curve of the neck, and the plans include close-up step photos for that section. Beginners should sort the parts before starting — following the steps in order gives a high success rate.
Q: How big is the finished model?
A: It is about 36 cm long and 16 cm tall, with a big span from nose to tail tip, so it stands out clearly on a desk. Every part is a standard brick with very tight dimensional tolerance, so it looks perfectly at home displayed next to official dinosaur sets.