Apply Flux and Wipe Excess

What happens here

Use a small brush to apply a thin, even coat of flux to the cleaned exterior of the pipe and the interior of the fitting. After applying flux, assemble the joint by pushing the fitting onto the pipe. With a gloved finger or a rag, wipe away any excess flux that squeezes out of the seam. This prevents the solder from running down the pipe when heated.

Goal: Coat joint surfaces with flux