Casting Knuckle-Duster or Meat Hammer. Aluminum Melting and Casting

I've seen an interesting design of a meat hammer which looks like a knuckle-duster and decided to make one.

Step 1: Cutting Polystyrene

First step is to cut a pattern of a knuckle-duster using a polystyrene.

Step 2: Making a Mold

During the next step a mold should be made.

Step 3: Casting Aluminum

When aluminum is melted it's time to pour aluminum into the mold.

Step 4: Open the Mold

After opening the mold I don't see a lot of issues. Knuckle-duster looks not bad.

Step 5: Final Process

After sanding the knuckle-duster is finished. Very comfortable to use as a kitchen tool for meat tenderizing.