I have a Thermal Dynamics CutMaster 51 on a PlasmaCAM bed that has quit right in the middle of a job. It spits an arc three times, pauses, and spits three times again. Air continues to run freely. It will not stay on. I'm sure someone has seen this before and will know exactly what the problem is. Based on the Googleing I've done, it's either a circuit board, a bad switch on the torch, or a bad solenoid. Changing out the combustibles and O-rings had no effect. Both lights stay green on the unit, the cap on the torch is not screwed on too tight, air pressure is 90psi. Help! I was not able to get my movie down to 508.8kb, so here is a link to my YouTube Channel with a ten second video of it misbehaving: