Do solder beads form during your selective or wave soldering process?
Are you applying the right amount of flux?
Check the amount of flux applied. Place or stick litmus, plain fax or thermal paper in your product holder or on your product and see how much flux actually reaches the process point; if possible, reduce the amount of flux applied.
Do you preheat your product to activate the flux?
If so, is it the right duration with the right temperature gradient? Implement trackable thermocouples and see what really happens on your product to be soldered.
How quickly do you dive in and out of the selective wave with your product?
Optimise the travel paths depending on the geometry and energy requirements of your product.
Does your selective solder wave have a defined solder return that prevents rising beads and warm nitrogen gassing?
If none of this helps, we recommend our Brush module with variably adjustable speed, brush monitoring, ionisation unit, suction and much more.
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