Glue or screw « MainGear » to « NeckHinge »
Use « GearHolder » and set « ServoGear » through it. Screw the actuator wheel sold with your HS-805BB servo to « ServoGear ».
Use your Arduino board and set your HS-805BB servo to 90°.
Puch it in the turntable.
This a bit tricky but can be achieved using a magnet on your screwdriver. Using the screw delivered with the servo, you need to screw the turntable to the servo inside « ServoGear ». Keep your servo at 90°.
Mount this assembly to the assembly « MainGear » and « NeckHinge »using some grease to ease the rotation. « GearHolder » should be aligned with « NeckHinge » and your servo should be still at 90°.
Fix the « LowBackRight » and « LowBackLeft » or « Temporary » to « GearHolder ».This will be the back of the skull.
Screw « Ring » to « MainGear ». Try to avoid slack between parts.
Use your favoriet pliers to mount « FaceHolder ».
You can mount both of them.
Now lets build the jaw. Take « JawPiston » and turn it inside « JawHinge » until you get 1cm offset between them.
Mount screw this on the turntable of your HK15298 or similar servo. Set your servo at 0° with the arduino board. Keeping the 1cm offset, « JawHinge » should be mounted at a 90° angle compared to the servo.
Mount screw « SkullServoFix » over the HS-805BB servo.
Put all 4 screws. Don’t mind the wires on my pictures they come from cameras.
Glue with acetonethe two « JawHolders » on both sides of whole assembly. It comes/fit on the « FaceHolders »
Now take your HK15298 assembly and slide it through.
Put all 4 screws to fix your HK15298 servo.
Remove the pre-support from « Jaw ». My « Jaw » shown on this picture is only a half part. It was a previous test print I did. Your « Jaw » is one piece print.
Screw « Jawsupport » to « Jaw ». Make sure the flat surfaces of the « Jawsupport » are on the inside.
Fix in « ThroatHole ». Mine looks different than yours. Sorry for this picture but « ThroatPiston » and « ThroatPistonBase » shouldn’t be already mounted, it comes in the next steps.
Screw « Neck » to « ThroatHole ».
Fix « NeckHinge » to « Neck » with a 8mm bolt (or print one from the hand)
Assuming you have already fixed your HS-805BB servo in the Torso assembly. Set your servo at 90° with arduino board. Turn « ThroatPiston » and « ThroatPistonBase » in a matter to get « NeckHinge » straight flat.
Screw « ThroatPiston » to its turntable keeping your servo at 90°.
Fix « ThroatPistonBase » to « NeckHinge » with a 8mm bolt (or print one from the hand)
Now the whole head should be able to go up and down if the servo turns from 0 to 180. Make a test with the arduino. Run this test carefully.
Leaving the head up, Slide the jaw assembly in to the head.
Bring the « JawSupports » through and mount them to the « JawHinges » and « JawHolders »
Using washers, set screws in.
Run a test on the jaw mechanism with Arduino.
ATTENTION: the jaw servo can only turn from 0 to 20° (I think) if more it might break something. Please Run your own test to check. (At the moment I write this I don’t remember exactly to how much mine could go. When I will plug it again I will rectify this)
You can run the cables of your servos in the « Neck ».
Now you should be set to move the head and the jaw through your Arduino.