I have purchased a Telwin 22 Kva spot welder second hand.It has been modified in this respect that both the timer switch and the current flow switches have been bypassed with a seperate switch called a "electro multirange" which is graded from 0 to 60.The person who sold it to me said that this switch does the function of both the other.By playing around with this switch it appears to me as if it only controls the timing.Is the seller correct with his statement??Secondly, I want to weld Brass onto stainless.I have brazed tungsten tips onto the electrodes.Can somebody help me with the correct settings on the machine for this ??