The most obvious work that needed to be done to the arms was scratchbuilding the curved shoulder and forearm armor parts which really distinguish the Gaz-R/L from the Galbaldy-ß. I wanted to make sure that these were suitably large and stylized so the models would really stand out.
I tackled the shoulder first, since it seemed easier. I first brought a front view of the Galbaldy-ß model into Adobe Illustrator and drew the basic shape of the shoulder armor over it, then printed it to scale with the kit. This drawing included both the large curved armor, and the reshaped base of the shoulder. I pasted the drawings onto sheet plastic with rubber cement, and used these as templates for cutting out the basic shapes I needed.
The base shoulder part is basically the same as the Galbaldy-ß shoulder, with a more rounded shape at the bottom. I glued the plastic profile shape (cut from the template) to the back of the kit shoulder part (I only needed the lower half), which gave me a base for fairing in the rounded shape with putty. I also glued on some thin plastic strips to help me keep the channel around the rectangular upper part and form a base for mounting the big curved armor. Then I glopped on some Bondo polyester putty and sanded the putty to shape. This had to be done to both front and back of one of the shoulders (the other shoulder is the same as the original kit). I later ended up sawing off the outer flared part, since it would be covered up by the new armor part anyway.
I also filled the back of the upper half of each shoulder part with epoxy putty (not pictured). This would make it easier to cast the parts later (since they're not so thin), and provide a larger mating surface for gluing the resin casts together.
The big curved shoulder armor was constructed out of 3 pieces cut from sheet plastic. The front and back were from the templates I printed, and the top piece was just a trapezoid cut to the correct measurements. After gluing these together and verifying that they fit the shoulder, I went crazy building detailed inner surfaces out of layers of plain and pre-scribed sheet plastic, and glued these inside of the armor (the side pieces were glued in at a slight angle, so the top of the sides is thicker than the bottom). These served to add detail and thickness to the armor. It's hard to see in the photos, but there are tons of little plastic rectangles forming an interesting pattern on the upper inside of the part.
I glopped some polyester putty on the top of the new armor part, then sanded it to a curved shape to round out the piece. After a few priming/sanding runs, I had everything looking smooth and uniform. Finally, I scribed a light panel line across the armor near the pointed tip (this is the separation point where the tips will be painted red or blue).
Thanks to careful measurements, the armor fits perfectly over the reshaped kit shoulder part, I wont even need putty when I glue it all together.
The forearm armor was constructed using completely different techniques than the shoulder. The compound curve made it impossible to just build this part out of sheet plastic. One of the Suku-Suku scratch articles in Dengeki Hobby magazine showed the builder cutting the basic shape for a Zaku leg out of styrofoam, skinning it with epoxy putty, then digging out the foam to form a hollow part. Seemed like a good method...
I used a knife, files, and sandpaper to cut the basic shape for the armor out of a piece of styrofoam (the stiff brittle kind found at craft stores, not the soft packing stuff, which was probably not the best choice). Then I mixed up some epoxy putty (eww...brown) and wrapped it around the foam, getting it as smooth as I could (not very smooth, that really was crappy putty). After the putty cured, I sanded and filed it smooth. Note to self: do not buy that cooper/brown colored plumbers putty again! It was hard to mix (I ended up with lots of bits of uncured putty to dig out and fill), hard to smooth when soft, and VERY hard to sand.
Next I dug out the foam. It stuck rather well to the putty, so I ended up melting the last bits of stuck in foam with MEK. The inside surface looked like a Nestle Crunch bar because of the texture of the foam. If I were to do this again I'd use a much denser foam. Lots more sanding and some spot putty took care of this problem. I shaped the round openings at the front and back of the armor part with sandpaper wrapped around appropriately sized cylindrical tools, and glued a plastic peg to the inside so it can plug into the original kits shield mount (I'll probably end up gluing it in place though). The 3 ridges were made from half round styrene rod with the ends rounded with sandpaper, glued on with CA after priming. This part ended up being a lot more work than it had to be, but I learned a lot, and the result looks great. Whew!
Below are some photos of the finished shoulder and forearm parts after priming and polishing.
Like most kits from this era, the elbow articulation leaves a lot to be desired. This is the result of problems with the original design (most designers didn't bother to actually plan for workable joints), and lack of good engineering on Bandai's part. Since the Gaz-R/L rely on some interesting melee weapons, I wanted a lot more articulation in the arms than is possible with the original parts. I spent a lot of time drawing different possible elbow joint configurations, and after several failed attempts came up with a joint system that sticks to the look of the design and allows a good range of motion.
The first problem is that unlike more modern designs, neither the upper or lower arm design allows much of a cutaway to make room for the elbow block to move. The solution was to build an elbow block that can extend out of the upper arm to allow the elbow to bend, and retract when the arm is in a more relaxed position.
Using a routing bit in my dremel, I first ground away the plastic inside the upper arm that holds the original elbow block to make room for a retractable part. I needed a new double jointed elbow block, which I started by building a simple rectangular box out of sheet plastic (some trial and error was necessary to get the length right). I drilled holes near the corners of the box on both ends to accommodate plastic rods (cut from the kit sprue), and installed t-joints which were cut down so they'd fit. Then I cut slots in the side of the box to allow the t-joints to rotate about 80 degrees..
Inside of the upper arm I installed a polycap to connect the new elbow block. It's held place in by a 3 sided box (u shaped). Since the elbow block is just plugged into this polycap, it can be pulled most of the way out of the upper arm, which gives it clearance to rotate (the polycap in the upper arm rotates a bit when this happens as well). The other end of the elbow block connects to a polycap in the forearms (allowing the same extension/rotation), which is held in place with short sections of plastic tube glued inside the arm halves.
The elbow was now able to bend well over 90 degrees, woohoo! Unfortunately, the power connectors (or whatever they are) that run from the shoulder to about half way down the bicep don't allow for a rotation point in the upper arm. So I had to add a rotation point at the center of my scratchbuilt elbow block.
I used a miter box to squarely saw the elbow block in half, and installed a simple polycap/rod rotation point. The parts are so small that I didn't have much space to work with, and the rod that plugs into the polycap is very short. I didn't want this to be popping out all of the time! From sheet styrene I cut end pieces to cap the sawed off ends of the elbow, and installed the rod and polycap before gluing them in place. I heated up a knife blade and melted the end of the rod flat. The mushroomed end of the rod keeps it from unplugging from the polycap. Then I glued the two elbow block halves together with the new rotation joint in the center, and sanded the whole assembly square and smooth. The assembly is a bit complex (and I still have to build 3 more!), but 7 points of articulation make for a nice poseable elbow. :)
After playing with it a little bit, I decided that I didn't like the squared off exposed edges of the elbow block when the arm is bent. So I filled the ends of the block with epoxy putty and sanded them to a rounded shape.
The arms don't need much in the way of added detailing. I did cut away the molded in vent next to the wrist and replace it with pre-scribed sheet plastic (I hate trying to fix seams in the middle of parts like that!). There is also a vent of sorts by the elbow on the forearm, which wasn't very well molded on the kit. I chopped this off with a hobby knife, and built a replacement out of sheet plastic. Basically it's a rectangle cut out of pre-scribed sheet, with a frame built up around it using plastic strips, then the frame was sanded to a beveled shape. It's small enough that it was quite a bit of work to make, so I took a mold and cast enough for the elbows on both kits.
The kit hands are no good, though at the time it was released articulated fingers were a big deal and were super cool. I planned to scratchbuild replacement hands which would be attached with ball-joints To simplify installation of the hands, I filled the end of one of the arms with epoxy putty to make a plug that fits snugly inside the forearm halves. Then I can just drill a hole to plug the ball joint peg into when I'm ready to attach the hands.
That's all I have documented on this build. I've done most of the molding and casting that will be required, but there's still a long way to go. Another project benched for now. If you'd like an email when I get around to working on this again, drop me a line.