I want to build some wooden molds tomorrow. Would you please help me figure out something? If I'm wanting to build a 1lb oil weight mold that is 3.5" wide, and make my bars 2.5" tall, how many inside inches would the length need to be? All inner measurements. What would the length need to be for 2, 3, 4, & 5lb oil weights? I know you figure it by using LxWxHX.40 but for some reason I can't figure out the lengths they would need to be. My wood is 4" wide but that doesn't matter because I'm only making my bars 2.5" tall. Please help me if you will. I want to make them as soon as I wake in the morning. Thanks in advance for your generosity in helping me with this.