@@ -28,11 +28,13 @@ We toolpathed the microspline part at the full ~2" long scale. This would be cut
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@@ -28,11 +28,13 @@ We toolpathed the microspline part at the full ~2" long scale. This would be cut
Given the long machining time, we ultimately decided to do a 1/3-scale test cut from a stack of 0.01" brass sandwiched between 0.25" aluminum. The perimeter of this toolpath measures 17.5 inches. With an expected cut speed of 0.18 inches/minute, the expected cut time is just about 100 minutes or 1 hr 40 mins.
Given the long machining time, we ultimately decided to do a 1/3-scale test cut from a stack of 0.01" brass sandwiched between 0.25" aluminum. The perimeter of this toolpath measures 17.5 inches. With an expected cut speed of 0.18 inches/minute, the expected cut time is just about 100 minutes or 1 hr 40 mins.
## Micromachining
## Micromachining using Zund G-3 L-2500
Using a .030" diameter end mill with amorphous diamond coating (<ahref='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).
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.
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 (<ahref='http://www.harveytool.com/ToolTechInfo.aspx?ToolNumber=72015-C4'>Harvey Tool 72015-C4</a>). It was fixtured using burnished PSA tape to both the substrate and the stock, with CA superglue applied between the tape layers.
Using a .030" diameter end mill with amorphous diamond coating (<ahref='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 (<ahref='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.
