Rusting Iron Cold-Cast Experiment



Rusted Iron Cold Casting ExperimentI've been dying to rust some cold-cast pieces and just got my iron powder order in. Since I worked on making a silicone mold this weekend, I figured I would go ahead and experiment on some smaller pieces during my downtime. Ultimately, I plan to apply the same technique to the Baby Doll Head candle holder that I will be casting more of in the coming days.

  1. I used the standard cold-casting technique of applying a thin layer of iron powder to the inside of my silicone mold.
  2. I then poured the resin into the mold and let it set. I used Smooth-Cast 300 resin for these pieces.
  3. I de-molded after around 15 minutes and cleaned up the flashing from the edges.
  4. I wiped them down with some mineral spirits and let them dry.
  5. I used a homemade recipe that I saw online to oxidize metal. It consists of salt, vinegar and hydrogen peroxide. I mixed the salt and vinegar together and kept the peroxide separate. I brushed on the vinegar/salt mix and then the peroxide. As I was experimenting a bit, I poured some salt on the pieces and let it sit for a while as I repeated the process. Overall, it took around 30 min to get the effect that you see in the photo.
  6. I'll put a coat of clear Sculpt Nouveau metal wax on these to seal in the effect and call these pieces done.

Overall, this was a very successful experiment and gave me better results than I anticipated. I'll be repeating this technique on a larger scale in the coming days.

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