how do i get paint off of my models?

I am looking to repaint some of my army that i did a while back, but its already half painted. Badly.

Any way, i was wondering if anyone knew if its possible to strip the paint off of the models, and if so using what?

( and just to say, the models i want to de-paint are a mixture of plastic and metal)

any help would be greatly appreciated!

 

http://www.lustria-online.com/threads/stripping-minatures-both-metal-and-plastic.5461/

Check that thread out.

 

Thanks!