Pure water jets are not as effective as abrasive water jets for cutting hard materials at large scales. Pure water jets can have kerfs as small as 0.076 mm, which is approximately the width of a human hair. This allows for small detailed cuts on workpiece material . Research into using pure water jet to machine aluminum at small scales is important, as this will allow small scale and precision machining of the work piece material. At micro scales, water jet cutting with typical abrasives is not possible because the abrasive particles are typically in the micron range which is around the size of the cut. At small scales a pure water jet is more effective than abrasive water jet machining, as special nanometer size abrasives would be needed at small scales. A pure water jet only needs the correct size orifice to conduct machining at the small scale. These are the reasons why this study uses a pure water jet to conduct small scale machining of aluminum. This study investigates the use of ABAQUS’s Smoothed Particle Hydrodynamics to simulate pure water jet machining of metals and compares the simulation results of a water jet machining of Al6061-T6 to experimental results using the same material. The simulation results compare favorably to experimental results with only 2.81% error in the width of the cut. The predictive FEM modeling is then conducted for other combinations of machining parameters (orifice diameter and inlet pressure). It is found that orifice diameter and inlet pressure have substantial influence on the width and depth of cut. The results of the study open new possibilities for machining metals using a pure water jet at the micrometer scale and at smaller scales.