After I built the Torus Pedestal table I was still intrigued by the possibilities of creating joinery by milling chunks of aluminum. In designing a new dining table I chose to use a similar technique to create the joint where the leg meets the stretcher.

My first step was to mock up the bracket which I had drawn in my sketch book. The wood mock-up allows me to check proportions and really visualize the steps that are needed to create the bracket.
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I start with a large piece of aluminum It is 1 3/4″ thick, 8″ wide and 36″ long.
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Step one is cutting this massive chunk into more manageable pieces.

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Then I am back at my horizontal mill precisely squaring the blocks. In this photo you can really see the coolant and chips flying everywhere!
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The blocks are measured with a large micrometer.
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The Blocks have been squared up and now the vise is rotated and I change the cutters. The heavy cutting is about to begin.
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The chips build up quickly.
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The grooves get cut and then the remaining triangles are removed with a saw. You can see the offcuts on the right side of this picture.
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Next I am off to the vertical mill. This machine, made by bridgeport, is more accurate, but less powerful than the horizontal mill. Here I will refine the surfaces created by the mill and saw.
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The cutting begins
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A smaller Micrometer is used to measure the thickness accurately.
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Things are looking good.
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The bottom corners are roughed out on a saw, then put back on the horizontal mill for finishing. Check out how the chip gets peeled off as the cutter just breaks the edge of the metal.
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The brackets are getting close. Time for some drilling and tapping.
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The through holes are drilled and countersunk.
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The rest of the holes are drilled and tapped.
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And finally the before and after on the scales. Almost 4 lbs of metal removed- about half the weight!
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Next stop, building the rest of the table.