3D Scanning a Silver Coin

The Problem:

The Republic Metals Corporation is one of the world’s leading precious metal refineries.  They are based out of Miami, FL, and provide services such as refining, assaying, minting, vaulting and hedging.  For their minting services, Republic Metals is able to fabricate large amounts of bullion of any design.  Republic Metals approached NeoMetrix Technologies wanting a digital copy of a new 1 oz. silver coin deemed Freedom, and do so with a high level of detail.

Traditional Method:

In order to replicate the design of a coin, one would traditionally have to find the original die, or cast mold, for the coin.  There would only be the physical piece itself available as a reference, and accuracy may be lost if it were to be replicated physically.  

NeoMetrix Solution:

Our solution is to provide digital data that provides unparalleled precision and accuracy of the coin’s surface. Among our list of capabilities is to scan any item at any size.  The coin has a relatively small volume being only 1/8 inch thick and taking up approximately 1.5 x 1.5 inches.  Capturing the seemingly microscopic level of detail can be accomplished using the Comet L3D scanner, which is capable of an accuracy less than 0.001 inches.  It is a versatile machine due to its ability to scan various volumes and its ease of use. The L3D setup includes a turn table that automatically turns the coin capturing scans at numerous angles in a short time frame.

The challenge with scanning the coin is its highly reflective surface.  A scanner cannot accurately capture data due to the projected light bouncing off the surface.  Our solution is to spray a layer of white powder on the coin while making sure that it will not disturb any of the details.

Within fifteen minutes, we have the scan completed start post processing of the STL mesh file.  Using Geomagic Wrap, we can quickly edit the mesh and eliminate any discrepancies like holes or spikes that may have been created during the scan.  Once that is completed, the final product is finished and can be seen in the image below.

NeoMetrix Advantage:

This case demonstrates some of the capabilities that we demonstrate on a daily basis:

• Highly accurate model.
• Capture small details.
• Quick turnaround for the customer.
• Eliminates guess work.
• Digital file can be preserved for future use.