I remodeled your mech in low poly form using a lot less split meshes. One thing I disagree with that people above have been saying is that you should use 1 single mesh for characters. This is true for organic characters (except for certain accessories), but you definitely should be using multiple meshes
for this type of character (non-organic) simply because of animation. Simple bone structures dont work for animating robots that have gears and pistons and things that need not deform but simply rotate and move. In these cases, you want to have multiple meshes that you can lock to bones instead.
Here's some screens, the model isn't textured, dont have that much time on my hands, but its 1214 polygons, a lot less than what you had.
Im not doing this to rub it in your face, I just think if you look at this it might help you understand how to properly model things low poly for game-use, and how to deform meshes instead of using single primitives all over the place.
Id recommend looking at some more tutorials on modeling, especially low poly ones, before making a thread like this. Especially since you dont know how to uv map, texture, or animate.
The .3ds file is attached below.
