Silver Coin: Congrats, Jeremy!

Goal: design and manufacture a coin made of silver and gold to celebrate my brother's coming marriage in September 2014. 

Materials:
  • Plate of 11 gauge fine silver
  • 10 gauge 14k gold wirel
  • 1/4", 1/8", and 3/64" square end mills
  • 1/16" ball nose endmill for surfacing
  • 45 deg single lip engraving tool 
  • Aluminum plate (for fixture)

Processes:
  • CAD work (SolidWorks)
  • CAM work (MasterCAM)
  • CNC machining and fixture design



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Back of coin. The hamsa represents protection from the evil eye, and the "5" refers to the names on the front -- as well as the hamsa figure.
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Front of coin, with initials of immediate family members. The center piece is a 14K gold inlay. The swirling pattern is a natural artifact of the toolpath used to machine the coin. I love it when that works out so well!
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Inlays were created by press fitting the gold wire into a hole that I milled out of the silver sheet. Then I used a flycutter to make the surfaces flush, and used an endmill to create a reference point at the corner of the sheet. The reference point was key in making the flip possible.
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Fixture plate used to machine the coins.
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The front of the coin immediately after cutout (I used a Dremel tool for this operation).
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Fixture plate post coin-machining. The contour cuts were full depth, but I left 4 tabs in to keep the coins in place throughout the final machining step.
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A closeup of the tabbing in action.
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The back of the coin after cutout.