How to make a flux usable for the dropjet fluxer

Introduction
The standard dropjet fluxer orifice has a diameter of 130 micrometer. To prevent the clogging of this nozzle the fluxes to be used for this system should have a low solids content up to about 5%. Depending on the flux viscosity and tackiness of the flux, even a lower solid content should be used.
Since most customers want to use the same flux as is used for wave soldering, one should check if that flux can be used as it is in the dropjet fluxer.
In case the dropjet fluxer nozzle is clogging up or is contaminating too fast, we advise to use the following method where still the same flux can be used.
Making flux suitable for the dropjet fluxer
If the flux is too thick or has a too high solid content, one can dilute the flux with the proper thinner, which is advised by the flux supplier. This has to be done to a degree that the flux functions with the dropjet fluxer, without clogging or too much contamination.
With the degree of thinning the amount of supplied flux should be corrected, so that the correct amount of flux and activator are applied on the area to be soldered.
Example
The amount of 'standard flux' to be applied should be F. The flux in the flux tank is diluted with 1/3 of the original flux volume to give the flux the correct dropjet properties.
Now the flux that should be applied must be 4/3 of the amount of the original setting, so 4/3 × F to get the right flux composition on the area to be soldered.
To put it in a general formula:
If the flux should be diluted with a factor X in relation to the original flux content, the flux application setting should be corrected with a factor (1 + X), to apply the correct amount of flux to the area to be soldered.
Alternative
If the amount of diluted flux to be applied becomes too large for the system to handle, then alternatively the use of a nozzle with a larger orifice of 270 micrometers could be a solution. The spraying behavior of this orifice may however give a larger overall contamination of the fluxer area.Information Sheet 059