sandite

Sandite refers to a type of industrial cleaning compound, primarily used in the United Kingdom. It is a thick, paste-like substance, often reddish-brown in color, composed of abrasive grit, such as sand or silicon carbide, mixed with a binding agent and a cleaning solution. Historically, sandite was widely used by railway companies to clean the surfaces of steam locomotives and their associated infrastructure.

The abrasive nature of sandite allowed it to effectively remove stubborn deposits like carbon, soot, grease, and rust from metal surfaces. It was typically applied by hand or with specialized equipment and then scrubbed or blasted away, taking the accumulated grime with it. While effective, its use has declined significantly with the phasing out of steam locomotives and the development of more modern and environmentally friendly cleaning methods.

Sandite's composition varied, but a common formulation included silica sand, oxalic acid, and sometimes detergent. Oxalic acid acted as a rust remover, while the grit provided the mechanical abrasion. Concerns about its potential environmental impact and the health risks associated with inhaling airborne particles contributed to its reduced usage. Modern industrial cleaning often employs high-pressure water jets, chemical cleaners, and other less abrasive or hazardous techniques. Despite its decline in widespread use, sandite is still occasionally encountered in heritage railway preservation settings.