(a) Breakdown of fields and currents in an arched, line-tied MFR. The foot points are anchored onto the conducting photosphere with a separation of 2x_f. The external fields, B_s and B_g, are generated by the Sun, while the internal fields, B_Pi and B_Ti, are generated by the currents in the rope. The figure is reproduced from Myers et al. (2016) and adapted from Chen (1989) and Chen & Krall (2003). (b) The MRX vessel used to create arched, line-tied flux ropes. An arc discharge is created between two copper electrodes and separated from the magnetic field coils by a glass substrate. The model in panel (a) corresponds to the pink plasma arc in the center of the image. Four coils were inserted into MRX in order to control the profiles of both the guide and strapping fields. The orange coils contribute to the guide field along the rope, while the blue coils control the strapping field across it. Control of the vacuum fields allows for control of the instability parameters for the torus and kink instabilities. The figure is reproduced from Myers et al. (2015).