I haven’t been real happy with my first attempt at the Zaku’s lower legs, so recently I’ve been trying to do better. The first version I did, the plan was to build the common parts of the leg (the area above and in front of the pods – as these areas are the same on both sides of both legs… so I could sculpt this stuff once and copy it for the two legs.) – however, the plan quickly (and rather haphazardly) changed to include not just the common parts but also a full sculpt of the two inner halves of the lower legs, stuck together. From there the plan was to recast the thing and then alter one half of each of two castings to form the asymmetrical lower legs.
If I kept working on that first sculpt I could probably improve it quite a bit – but there were some problems with how I addressed that sculpt that I think would have made it needlessly difficult. First, the whole lower leg was built up out of just five cross-section pieces: a center line, two offset 5mm from the center, and two incomplete profiles that I did for my initial plan of sculpting just the common parts of the leg… But sculpting the whole leg instead of just half of it meant it would have been a lot harder to take a contour gauge to the thing, or to compare halves in different ways to check symmetry…
So the first alternate approach was to use more cross-sections. Instead of profile cross-sections, I used horizontal cross-sections, spaced at 5mm intervals.
However, what struck me about this approach was that, as with the shoulder armor I did a while back, sometimes it’s not the exact curvature that counts, but rather the exact placement of edges… In this case, the ridges near the knee and the boundary of the pod are probably the most important for now, and the boundaries of the thruster openings and so on will be important later. Working with just horizontal cross-sections meant that the diagonal and horizontal pod edges were almost completely ill-defined by the cross-sections, and the vertical leading edges were poorly defined and very sensitive to errors in placement of the templates… Continuing with this approach, I’d ultimately wind up in a situation like what I got with the shoulder armor – having to refine the sculpt to try and correct those edges.
So I tried again: this time, I started with the edges I was interested in. I drew out the path the edges followed, I picked out elevation data along that path using the Blender model, and created strips that could be bent along that path. Then, when filling in between the templates with epoxy putty, I’d be able to know (almost) exactly where the pod boundary should be… So long as the strip was placed correctly, and so long as it remained more-or-less perpendicular to the center plane, I’d have a good indicator of where the boundary should be.
So after I got my plans together for this method, I started putting together one half of one leg (the inboard side of the right lower leg) – it took a while and it was difficult to get the strips to follow the paths… When that was done I used the horizontal cross-section patterns I’d made for the previous attempt to flesh out the shape of the pod, and then started filling in with epoxy putty.
I think this approach has worked out very well! Easily the best-looking of the three attempts so far, and this is before doing any refinement work on it. I think the method of making elevation strips to follow the paths of prominent edges is a lot easier to deal with than using cross-sections to flesh out the volume of the part. Though the real test will be to see how the other three turn out – will the matching parts match? Things like that. Like I said, Mitsuaki Misaki I ain’t. In the Scratch Build Manual he built these lower leg parts at least three different ways, and they all matched… I don’t know how much time he spends on something like that, but damn, man…
As a side note – my last update to the site was four months ago. I spent some of that time trying to complete projects for Tekko (I failed) – but then there was a huge flood. Our garage filled with water and some of it seeped into the basement, too. My workspace carpet was ruined and I had to spend a ton of time tearing the place apart and I’m still picking up the pieces. It feels good to be getting some model work done again.