Purchased parts from a website but the parts ain't threaded
 

So I recently purchased a HPI 4.3x15.5mm Ball cup for my HPI sprint 2 flux and I've noticed that the ones built onto the RC was threaded and the ones i bought weren't. Is there something I'm missing? How do I thread my own parts? Was this supposed to happen?

I've never bought a ball cup that was threaded. If you can't get the rod that goes into it to cut the threads you can use a tap to start the threads and then use the tie rod to continue the threads as deep as you want to make them.