alphamaping textures

i made a texture for a disk break and used alphamapping for the holes and it looks great but when i put something behind it i see through that too! cani fix this?

from your pic it looks like the holes in the rotor are not holes, but just white dots. If your texture is white dots, then you actually need to negative Alpha apply the texture to the rotor. Then the parts of the rotor mesh that have a white dot will be transparent. Ensure you have turned on Ztransp in the rotor material, and you should see the black post through the dots.