Black or yellow solder joints?

Cause 1: the exposure of the tungsten needle is too long to cause the insufficient protection of argon

Solution: adjust the tungsten needle to keep the exposed part around 8mm.

Cause 2: the output power of the cold welder is too large

Solution: adjust the pulse time and pulse current of the machine

Cause 3: the surface of the workpiece is dirty

Solution: removal of oil and oxide impurities on the surface of the workpiece

Cause 4: argon has no or no argon gas

The solution: when stepping on the foot, check whether there is argon gas ejection from the ceramic mouth. If argon is not felt, check if the valve is open and the pressure relief valve is working properly.