Yes, you need to season a cast iron Bacon Press to prevent it from rusting. Seasoning is the process of coating the metal with oil, which creates a barrier that protects the metal from moisture.  You can season your Bacon Press by rubbing it with vegetable oil and then heating it in the oven for 30 minutes. Be sure to let the Bacon Press cool completely before using it. If your Bacon Press does rust, you can remove the rust by scrubbing it with a stiff brush and then re-seasoning it.