Spot Cleaning Flux Residues Using the Chemtronics BrushClean System

Chemtronics manufactures a large variety Flux-Off brand flux removers to satisfy many different requirements, for example if the cleaner needs to be nonflammable, safe on sensitive plastics, or have extra cleaning strength. Many Flux-Off cleaners are available with the BrushClean™ system with allows for controlled application of solvent.

When a large area needs to be cleaned or rinsed, the trigger sprayer can be used without any attachment. For spraying into tighter areas, like under low standoff components, the straw attachment can be used. The BrushClean system allows you to clean in a more controlled way, avoiding cross contamination and preventing solvent from reaching sensitive components and coatings. It also minimizing solvent usage.

• No attachment for cleaning or rinsing large areas
• Straw attachment for spraying into tight areas, like under low standoff components

Chemtronics Coventry brand consists of a variety of swabs and wipers dedicated to precision cleaning of sensitive electronics.

The 4” x 4” (10.2cm x 10.2cm) Coventry Econowipe™ (part #6704) is a polyester-cellulose lint-free wiper that is ideal for use in combination with the BrushClean system because it is both strong and absorbent. For areas that are more likely to tear the wipe and create particulates, like the underside of a through-hole PCB, use either the Chemtronics Twillwipes™ (C900) or Coventry Poly-Wipes (6209).

There is a common misconception that you can spray flux residues or swab with isopropyl alcohol and the contamination will evaporate with the solvent. What actually happens is the solvent evaporates but leaves the residue behind. This might hide the problem, since the flux is spread over a wider area, but the potential for corrosion and dendritic growth from ionic contamination hasn’t changed. Using a wipe in combination with the brush allows you to not only break down and dissolve the flux residues, but also remove them from the PCB surface.

Before you start, take necessary precautions to avoid electrostatic discharge, like a grounded wrist-strap. Next attach the brush to end of the spray nozzle and remove the plastic safety-lock tab.

To use a Flux-Off flux remover with a BrushClean system, place the wipe over component connectors to be cleaned. Lightly spray or dribble out a small amount of solvent while pressing down on the wiper firmly with the brush. Move around or scrub with the

brush over the wipe to provide addition agitation. Shortly you will see the solvent with the dissolved flux wick up into the wipe.

Repeat this step for each side of the component, moving to a fresh part of the wipe each time.

Lightly spray and scrub over connectors

Availability

Flux-Off Products with Brushclean System: ES835B

Flux-Off Rosin 5 oz / 141 g aerosol: DEL892B        

Flux-Off Delta 6 oz / 170 g aerosol: ES7208B         

Flux-Off CZ 5 oz / 141 g aerosol: ES897B                       

Chemtronics Coventry Econowipes

6704: 4x4" (10.2 cm x 10.2 cm), 1200 wipes/bag

6704F: 4x4" (10.2 cm x 10.2 cm), 100 wipes/bag

Chemtronics Twillwipes

C900: 9x9" (22.9 cm x 22.9 cm), 150 wipes/bag

Chemtronics Coventry Poly-Wipes

6209: 9x9" (22.9 cm x 22.9 cm), 150 wipes/bag