Skipton-based Guyson International, a leading UK manufacturer of industrial finishing equipment, has recently installed a specialised version of its Formula 1400 blast cabinet at an aeronautical defence manufacturer, for the selective removal of conformal coating from printed circuit boards (PCBs).

If during testing or usage a circuit board develops or registers a fault then instead of scrapping the entire board, which could incur very considerable costs, selective conformal coating removal can be undertaken so that the damaged components can be replaced or reworking (such as re-soldering) can be undertaken.

This specialist Formula ESD version is based on the well-proven Guyson Formula 1400 blast cabinet that has been specifically adapted for this application and comes complete with a Guyson 21 twin bag dust collector.

Blasting is undertaken with the stand-alone pressure-fed Pencil Blast, with the choice of blast media depending on the type of conformal coating; options include walnut shell, sodium bicarbonate, plastics and wheat starch.

All blasting operations generate some level of static electricity, and if this potential is not conducted away an electrostatic discharge (spark) can occur. Hence, this Guyson Formula ESD version comes equipped with preventative measures to enable safe blasting.

Moreover, this Formula ESD version of blast cabinet is supplied with ultra-violet lighting. This is because some conformal coatings that are UV cured give an enhanced fluorescent response, which makes the coating more visible under these ‘black lights’, so aiding operator accuracy when blasting.