Laser Cleaning Railroad Signal Lamp

Brass knobs look brown and sticky at the start. A stopped pass leaves them golden, not salmon-colored and powdery on the knob itself.

Cast iron arrives under rust and foundry scale. After the pass those films are gone and the graphite stays in the metal, not blasted out of the face.

Soda-Lime panes arrive under paint, soot, and soil. After the pass the laser leaves the clear glass intact, not checked, scratched, or hazed.

Carbon steel looks scabby with outdoor rust before work starts. Afterward the operator has bare iron that is still sound, without a pit track.

Iron arrives under rust and mill scale that hide the face. After the pass those films are gone and the metal is bare, not abrasive-blasted or pitted.

Alabaster arrives chalky under soot and handling soil. After the pass that soil is gone and the soft hydrate is still intact, not grooved or sugared.

Aluminosilicate cover glass arrives filmed with soil and fingerprints. After the pass those films are gone and the pane stays clear, not starred or marked.

Borosilicate flasks look filmed and cloudy at the start. Once the operator stops, the residue is gone and the vessel is uncracked.

Copper looks brown and dirty before a stopped pass. Afterward the piece shines and the dirt is gone, without ripples or a wrinkle.

Mahogany arrives under varnish and stain that hide the figure. After the pass the laser leaves that open grain in place, not sanded flat.

Nickel arrives dull under oxide and heat tint on plate. After the pass the laser leaves the metal bright, not thinned or pitted through.

Redwood siding looks coated and weathered before work starts. Afterward the operator has bare boards that are still sound, without a char streak.

Slate roofing looks stained and sooty before work starts. Afterward the operator has cleaved sheets that still hold together, without flake-off.

Tin stock arrives dull under oxide on a soft, low-melt face. After the pass the laser leaves that metal smooth, not beaded or rough.

Tool steel dies look filmed and oxidized before work starts. Afterward the operator has a still-hard working land without a blue temper stain.

Aerospace parts arrive painted, primed, or oxidized. After a dry pass the coating is off the metal, and the surface is not chewed or filled with grit.

Battery busbar faces looked dull and filmed before joining. Once the head finished, the land showed through so amps could move across.

Heritage architectural work looked stained and tagged on the elevation. Once the head finished, the stone showed through and the old character remained.

Paint and coating sit on steel and aluminum as a thick film. After the pass that film is off and the metal is ready to inspect or recoat.

Rust sat as a flaky orange crust on damp field plate. Once the head finished, the metal showed through and a fresh coat could go on.