I'm currently working on the fuselage and cockpit designs, letting them run in my head for a while mainly to incorporate how the hip will connect to the fuselage. With it was an incessant itch (that I have had since the initial build) to add a dual opposing piston that will run and connect the back of the thigh to the front of the knee in between the knee intermediary. This serves both as void filler, as well as functional mobility to the leg, which theoretically speaking, gives the leg more hydraulic power and support.
Instead of the usual exposed piston barrels like what I have done previously, I decided to encapsulate these in a plaplate "box." On very rare occasions, I do use superglue for quick bonding work, as well as the fact that these tubes are unaffected by cement. I glued the pistons on a slab of 1mm HIPS, cut it to size, and glued the other side. I then cemented a small piece of HIPS on each end, boring holes aligned to the tubes. I then cemented 0.5mm HIPS on the sides.
I drilled holes 1mm + 0.5mm deep on the wider side of the box, rounded the tips of 3mm round beams, and cemented them into place. I made the usual T-shaped beams for the shafts.
This box piston will be held in place by the side pegs, which in turn will move freely along the length of the knee intermediaries. I ran this scenario over my head quite a few times as I was doing the foot and the shin armor when I realized that that section will look rather empty.
I modified the thigh and shin frames to fit the box piston by cutting away a bit of material from each that come into contact when the leg is folded. I also added a few strips on the calf section of the leg, both to reinforce the part and as detail prep. The thigh and shin "cheek" frame intermediaries were also "slightly" modified to hold the T-shafts of the pistons. Though the modifications were simple enough, I made a few mistakes aligning the holes, so I had to plug and re-drill a few times, which took a lot of time just waiting for the cemented plugs to cure.
Without actual measurements and just basing it on visual estimates, the box piston fits perfectly inside the void of the legs (which I had to modify) when the assembly is folded.
In order for this to work, the intermediaries had to be modified as well. I drilled 1mm holes 2cm apart and drew a straight line between them, drilled a few more holes, and progressively enlarged the holes to 3mm to fit the box piston pegs. I shaved of the excess plastic with a knife, then filed the surface smooth.
Test fit. I wasn't sure if this will work, or will lock the entire knee assembly, ruining hours upon hours of work and imagination, but sometimes, I do amaze myself when something this random actually works the first time I do it.
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Trivia: This is one of the rare posts wherein I didn't need to include a thumbnail...
1 comment:
a mix of modelling and engineering... impressive!!!!
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