How to Tighten Up a Loose Figure
There are three things you need to check and might have to fix for a loose figure. The o-ring, loose neck or arms, and a loose knee joint.
The easiest thing to check and replace is the o-ring. Remove the back screw and take the torso apart. If the o-ring looks stretched out, cracked, or is broken it will need to be replaced. You'd be surprised how just by replacing a stretched out old o-ring with a new tighter one, the figure will tighten right up.
Loose Neck or Arms
If the figure has loose arms or a wobbly head, a drop of super glue will go a long way. Put a drop of glue in the head socket, arm socket, or at the bicep swivel and then move the part around while the glue dries. It is best to do this for about ten minutes or so to make sure the parts do not stick together. The glue will fill in any spaces and make the joint much tighter.
For loose knees, you first have to take the legs apart at the thigh screw. If the peg is intact but still lose you can use the superglue trick here. Place a drop of glue on the peg, put the leg back together, and work the leg joint for about 10 minutes. If the glue trick does not work you can use a very small piece of a plastic bag. Pull the piece tight over the peg and insert through the hole on the top of the foot part. You may have to cut any extra plastic away before putting the leg back together.
Peg broken off
If that still does not do it, you may have a broken peg. If the peg is stuck in the hole, first gently remove it with pliers. If it won't give then you may have to just drill the peg out with a dremel. Now, take the broken off peg or a peg from a "donor" that fits through the hole and glue it into the hole on the thigh. Once it dries put the leg back together. This should leave the knee joint tight. If it is still a little loose you may have to use the drop of glue or plastic bag trick to tighten it up.