I was posing my arcadia YF-19 and noticed that the ankles had loosened. I had dropped some future into the ankle joint around the time that I got it, and that seemed to work. Well seeing as to how they had once again become un-pose-ably loose, I decided to do it right.
This is not for the faint of heart. If you have an reservations about harming your figure, please do not attempt. Removing the ankles in this way will slightly stress the plastic on the inside of the foot.
Make sure your feet are fully extended to allow you the best access to the ankle.
Remove the foot covers. There are 2 covers that are pegged in and held by a screw.
Remove the screws on the inside of the foot. The rear of the feet will require you popping the foot piece off of the metal pin in order the access the screw.
Rotate and bend the ankle joint to work the pins loose. I had to apply a lot of force to do this. Go steady and slow, applying more force as you go. Just do a little at a time.
This was the gap I was left with after removing the foot. I ended up with small stress marks on the inside of the foot where the metal pin holds them in place. I consider this to be a minor issue, because the foot covers will go back on covering this area.
I used a q-tip to apply future polish to the ball joints, and I also lightly coated the inside of the ball socket on the foot. I waited 20 minutes, and than applied a second thin coat.
A little over 8 hours later I reassembled the feet and now have a 19 that won't topple over.
I hope this helps you if you decide to fix yours.