Fuse metal together by directing huge amounts of energy into small areas.
Mounts and solders ribs to shotgun barrels to form double barrels and for use as aiming sight: Brushes flux onto shotgun barrels to prepare surface for soldering. Files and fits dovetail butts of barrels together and hammers pin through holes in barrels to lock them together. Inserts spacers between barrels and mounts barrels in fixture. Aligns rib between barrels and drives wedges between rib and barrels to secure rib. Heats assembly in gas-fired oven to specified temperature for soldering. Melts and flows solder along adjoining edges of rib and barrels, using gas torch. Positions and secures barrels and sighting ribs in aligning fixture and solders ribs to barrels. Drills vent and bead holes in barrels, using bench drill. Places soldered barrels in wire basket and moves barrels through acid bath tanks and rinse water, using overhead hoist, to remove excess solder and flux.