README.md

## Micromachining using Zund G-3 L-2500

Despite being a very large-scale tool, the Zund was surprisingly effective at micromachining with its 50kRPM router spindle.  To fixture the stock, we first faced a sheet of aluminum to provide a rigid surface.  Then we applied PSA tape to both this surface and the underside of the stock.  We burnished the tape using a small stainless rod.  Then we applied CA glue to the tape and bonded the stock to the substrate.

Using a .030" diameter end mill with amorphous diamond coating (<a href='http://www.harveytool.com/ToolTechInfo.aspx?ToolNumber=72030-C4'>Harvey Tool 72030-C4</a>), we machined the flexure from .020" Aluminum 2024 sheet in 2.5 minutes (comparable to the waterjet).  300um step down, 20 mm/s, 50kRPM.

Here is a 50% scale flexure (.010" beams, .015" gaps) machined from .020" thick Aluminum 2024 sheet using a .015" diameter end mill with amorphous diamond coating (<a href='http://www.harveytool.com/ToolTechInfo.aspx?ToolNumber=72015-C4'>Harvey Tool 72015-C4</a>).  This took about 8 minutes, but I think could be run faster.

<img src='flexure-0.5-penny.jpg' width=300px>

Here is a paper about micromachining aluminum using tools with diamond-like coatings: <a href='https://pdfs.semanticscholar.org/a9d5/532adaf5fa1b22940a921fc9cdf2ea76b555.pdf'>Diamond coatings for micro end mills: Enabling the dry machining of aluminum at the micro-scale, Heaney et. al.</a>