I began by CAD modelling the front thigh plates by drawing curves in 2D, then pulling them out into 3D. I have never modelled leg armor before, so to get the curvature of the surface took some trial and error. I’m thinking that modelling curvy objects like this would be easier in a 3D sculpting program like ZBrush, but for now, Rhino will have to do.
After the model was done and sized correctly, I split it into 4 separate batches of several pieces each, and sliced it for printing.
After everything was printed, I assembled and glued all pieces together with superglue, and then used my ABS/Acetone sludge I use on my printer beds for adhesion to smooth out and fill in the seams. Since the sludge contains the exact same type of ABS as the printed parts, once the goo dries, it creates a permanent bond with the plastic underneath, fusing the parts together. (NOTE: this was more of an experimental approach to gluing parts, and is actually not the best; sanding these seems leaves behind a porous surface that needs a bit of work to fill in. I have started using epoxy putty for this step with fantastic results).
Next, I sanded the surface down with an orbital electric sander using 120 grit paper sanding disc.
I primed the parts, and used more spot putty to touch up the areas that need it, followed by sanding, priming, more spot putty, until the parts were perfectly smooth and ready for molding.
Next, I used some foam to build up the empty spaces under the masters to elevate them off the table...
… measured out and mixed up some Rebound 25 silicone,
… degassed it in my vacuum chamber as I do with all my silicone,
…and brushed on the first layer.
I did two more layers after this, before adding a silicone thickener called Thi-Vex to the fourth layer to thicken the mold.
Once the silicone cured, I mixed up some Plasti-Paste in a reusable container, and applied it to the molds to create the support shell.
Once this cured, I demolded the masters, and using the cold casting technique I explain in some depth on this page I cold cast the final pieces in aluminum-infused 65D resin.
After demolding and trimming, the pieces were ready for polishing with #0000 steel wool and painting.
A quick coat of black primer...
… followed by these colours which I used for the rest of the armor.
I then painted the edges of some of the details silver, and the recessed areas with a black acrylic colour.
I used elastic straps to connect the two halves in the same manner I did for the thighs, and epoxied some metal braces to the shins to ensure that the two halves would stay put lined up, and not slide off one another.
Adding some velcro loop strips to the inside for padding completed the lower legs.
Thanks for looking!
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