Leg Assembly

Specifications: The legs must be mounted on a Plate 8x8 base. No part of the legs may extend past the base. The legs must be at least five bricks high, not counting the Tile 2x2 with Pin.

Interfaces:

1. Torso: To mate with the torso, the leg assembly must have a Tile 2x2 with Pin (or equivalent) at its top. No part of the legs may extend above base of the pin.

Torso

Specifications: The torso must be at least 3 bricks high and only 3 or 4 bricks wide. It can be as deep as the designer wants but may not extend below the base.

Interfaces:

1. Shoulders (x2): To mate with the shoulders, the torso must have two Technic Brick 1x2 With Holes*, one on each side. No part of the torso can extend sideways farther than these pieces. There must be at least two bricks' height in the torso below this piece.
2. Leg assembly: To mate with the leg assembly, the torso must accept a vertical Technic pin in its base. This might be done with a brick, Technic plates, or SNOT construction using a brick with a Technic hole

*To achieve an offset, it is permissible to use a Technic Brick 1x4 with Holes instead. The extra hole should be filled with a Technic Pin 1/2 with the stud facing the inside (or similar) if possible so that only one position is possible for the shoulder.

Shoulder

Specifications: The shoulder must be 2 or 3 studs wide. It extend as many bricks up from the torso interface as the designer wishes and can decend up to two bricks below the torso interface--but no more, to allow the torso to turn freely. It can extend in front or behind as far as the designer wants so long as it won't overbalance a Mech.

The shoulder should be built exclusively for the left or right side of the Mech, so that any weapons mounted on it face the front of the Mech when attached to the torso.

Interfaces:

1. Torso: To mate with the torso, the shoulder must have a Brick 1x2 with 2 Pins on one side. No part of the shoulder may extend sideways past this part.
2. Arm: To mate with the arm, the shoulder must have one Technic hole on the opposite side from the Brick 1x2 with 2 Pins. This interface may be higher or lower than the torso interface but its depth must be within the Brick 1x2 with 2 Pins. This hole could be in a Technic Brick 1x1 with Hole or a Technic Brick 1x2 with Hole, among other possibilities. The shoulder may extend sideways 1 stud past the Technic hole, as long as the hole itself is not blocked.

Arm

Specifications: The arm has no mandatory dimensions, but should be built so as not to overbalance a Mech. The arm should be built exclusively for the left or right side of the Mech, so that any weapons mounted on it face the front of the Mech when attached proper-side-up to the shoulder.

Interfaces:

1. Shoulder: To mate with the shoulder, the arm must have a Technic pin (preferably a friction pin) at its end. This pin must allow for free rotation in a space no larger than a brick, so it should be provided on a Hinge Arm Locking with Single Finger and Friction Pin, or as a Friction Pin attached to something else narrow such as Technic Axle Joiner, another Hinge Arm piece, or Technic Pin Joiner.