I made a little more progress on my Primaris-scale Mark V Dreadnought, building up the sarcophagus and the shoulder armor.
The basic shape was already there, but because I had removed the outer sarcophagus covering, I needed to move the shoulder armor in, make it taller, and then trim the outside edges. My plan was to affix layers of thick plastic card over the existing armor plates. First, I cut four sections that were the width I wanted (no precise scaling measurements here; I just eyeballed everything), and I glued a square rod along the inside edge. I also sliced off the rivets on the armor so the plates could glue on flush.
I glued the new panels over the front armor plates. (The armor wasn't glued to the dreadnought body; it will be kept separate and attached after painting.) The inner edge is aligned closer to the sarcophagus, and significantly overhangs the original plate.
Then, I glued the top and front armor plates together at the corner. I trimmed the front panels along the corner line, and then glued the new armor over the top.
Here you can see how I cut the angle of the square rod to fit against the front plate.
Next, I trimmed the top plate and sanded the corner to match the angle and create a seamless join.
The outer portion of the original armor was then trimmed to the width of the new armor plate.
I also built up the little flange at the bottom with more styrene card.
The flanges were trimmed and sanded to match the shape and angle.
All of the imperfections along the seams were filled with Aves Apoxie Sculpt, and the bottom of the front panel was extended to align the edge at the corner.
I let the putty harden and then sanded everything to get smooth edges and sharp corners.
With the armor panels finished, it was time to add surface details. I marked out the panel lines...
...and then etched them into the plastic with a sharp sculpting tool and a metal ruler.
I glued on some rivets, and the shoulder armor was just about finished.
The thicker armor plating sat at the same level as the sarcophagus. But the sarcophagus needed to protrude farther forward, so I extended it extended with some square plastic rod and Apoxie putty.
Here's how everything looks so far. Now I need to build the boxy covering for the arms.