Step 1. When the temperature of the nozzle is 300-360 ℃, the regenerative operation is performed.
Step 2. Put the weld in the resurrection ointment and wait for a few seconds.
Step 3. Clean welding nozzles with solder sponge or copper wire.
Step 4. Tin is plated on the welding nozzle. Repeat 2-3 steps when the regenerative effect is not obvious.