Should I add water to the flux?

Is it normal to add water to the flux, and if so, how do you tell it’s too thin or no longer effective?

Most fluxes are water-based compounds, and the consistency should be thicker than honey. Mayonnaise consistency is best, because when you layer the part in the flux, it should form a protective layer. I’ve seen companies let the flux air dry before the cycle which ensures a nice coating on the part. In all cases, the consistency should be from thick honey to mayonnaise consistency. You can add water to the flux if it’s drying out, but over time you may dilute it too much and it’ll lose effectiveness. Flux isn’t expensive, so using more flux, and thicker flux, is better.