The MixTrain is an advanced stand-alone device that enables sum or difference frequency mixing of single frequency CW laser beams in periodically polled crystals. High mixing efficiencies are achieved by precision temperature control to ensure optimal quasi-phase matching over the entire tuning range of the Matisse®. When combined with a high power fiber laser, sum frequency output exceeding 2 W is readily achieved. The MixTrain is equipped with all optics needed for combining input lasers, mixing in periodically poled crystals, and separation of the desired sum (SFM) or difference (DFM) frequency mixing output from the residual input beams. The platform includes a lens to collimate the output, and an isolator to protect the fiber laser from damage due to back reflections. Periodically poled mixing crystals are mounted in a removable configuration to allow for alternate fiber input wavelengths. The mixing crystals are housed in a temperature stabilized oven with motorized control, providing hands free tuning over >100 nm of the visible spectrum. When pumped with the Matisse C and the appropriate fiber laser the MixTrain provides hands-free, all solid state output from 422–670 nm for SFM – a attractive and versatile alternative to a CW dye laser. Flexible configuration of mixing and separating optics enables output from 1.1–4.2 μm for DFM, depending on fiber laser input.