Spent the last year testing different elements of a sander to see how they performed. This is the first machine with all of the components purpose built into it. Of Course as soon as I finished it I found about a dozen ways to tweak it for improvement. Will incorporate those changes in the next machine. I will build a few of these until I feel I have found and incorporated all of the beneficial modifications. The aluminum cuts like wood on my miter saw and welds like metal. The close tolerances of the extrusion deliver an accurate frame with little effort and reduced fabrication cost over steel. It is powered by the 3HP, 3PH, 400HZ, 220 Volt, 24,000 RPM, Liquid cooled, 11 pound spindle motor that has been in testing on my old test frame for the past 9 month and earned a place on this machine due to its very impressive performance. The top belt speed it over 7100 sfpm. If you have seen my older videos then you know that I like a powerful and fast machine. My original 2 x 72 had a 5HP motor so I feel the bar was set high for this tiny motor and also feel that it met the challenge during torture testing and exceeded expectations all around.