How to protect paint jobs on miniatures??

[Firestorm]

In the past, I have purchased the Deluxe Ogre and Deluxe GEV games, several boxed Ogre miniature sets, and several individual packaged Ogre miniatures.

I have assembled and painted most of them. I painted them with acrylic paints. I have noticed that the acrylic paints seem to wear off some parts of the miniatures relatively easily as the miniatures are handled. Up to this point, I have gone back and touched up the paint jobs as needed.

My sons and I are anxious to try playing some Ogre/GEV scenarios with the miniatures, but I am hesitant to use them because I am afraid to cause the paint to wear off while handling the miniatures during gameplay.

Richard Kerr has done an excellent job at painting the miniatures that I have seen.

Is there a better way to protect the paint jobs on the miniatures and make them more durable?

Is there a finish I can apply that might help?

Thanks.

Randy