You can make a rigger who can't hack, it just isn't an overly good idea because people can hack your drones and you can't do jack about it. Also, there's a significant overlap between stuff you need to rig and stuff you need to hack (eg, a good commlink). I would suggest starting by looking at the two riggers in my sig: the Mercenary Rigger for a mundane rigger with secondary skills in hacking and street samurai, and the Info Savant for a technomancer rigger with secondary skills in hacking.
You could in theory take the Mercenary Rigger and just drop the hacking skills and gear and buy other things with it. There's not much room to actually be better at rigging by doing so, though, and like I said, it isn't a terribly good idea. If you want to do it anyways, though, by all means. I would suggest that a better way to think about it is "be a good rigger, then spend leftover points being a good hacker."
