I find, when I am painting a miniature and I use the color white, it either ends up with too translucent or, after enough coats to make it opaque, it ends up chalky. Anyone know a work-around for this?

Are you using acrylic paint? Acrylics are usually very solid and non-translucent. Maybe also your brand is off

Acrylic, and I've used several brands. It's an issue when I'm working with a darker base or a metallic base. I'm doing a lot of steampunk-esc stuff, so a lot of my basecoats are metallic.

Huh, haven't experienced enough with metallic bases to give a good solution. 

Have you tried thinning with a binder medium? If not enough of the white pigment is being held to the surface, that may be the answer.

I have struggled with the same problem and I've found a good enough method to fix this. I first paint the area very light gray, then couple layers of thin pure white and finally apply a thin layer of glossy finish, like Games Workshops 'Ardcoat to erase most of the chalkiness. This mitigates the problem enough for me that the white looks quite solid and a bit glossy.

Huh, I haven't tried either method. I'll give both a shot and see what I get.