Things You'll Need
Instructions
Separate the action figure's arm from its torso.
Use a razor knife to shave off any old joints or protruding pieces of plastic. Sand the connection areas on both the arm and torso until they are flat and smooth. Continue shaving and sanding until both pieces fit together tightly.
Mark the center of the joint on the torso where the arm will attach. Mark the center of the corresponding area on the arm.
Drill a 1/8-inch-diameter hole, 1/8-inch deep, into the mark on the torso. Place a drop of super glue inside the hole.
Screw the pointed end of a 1/8-inch-diameter 1/2-inch-long rounded head screw into the torso hole with a cross head screwdriver bit. Leave 1/8 inch of the screw sticking out.
Pack sculpting clay around the head and stem of the screw, creating a 1/4-inch-diameter ball on top. The sculpture should resemble a lollipop.
Add or remove sculpting clay until the sculpture protrudes from the torso 1/4 inch. Make sure the diameter of the ball stays consistent at 1/4 inch. Let the sculpting clay dry for four hours. This will be the ball portion of the ball and socket joint.
Drill a 3/16-inch-diameter hole into the mark on the arm; this will be the socket. Make the arm socket 3/32 inch deep.
Heat up the socket with a heat gun. Press the arm onto the torso while the plastic is still hot and gently move the arm back and forth so the socket begins to contour to the ball. Allow the plastic to cool for one hour.
Cut a slit in the top of the shoulder on the arm. Make the slit the same width as the stem of the ball and move the arm up and down, making sure the stem of the ball locks into the slit. This slit will allow the arm to move up and down on the ball instead of just around in a circle.
Remove the arm and paint the ball and inside of the socket to match the figure.
Heat up the socket with a heating gun and press the arm back onto the torso. Add additional sculpting clay to increase the diameter of the ball if the socket seems too large.
Repeat the entire process for the other arm, both legs and head if desired.