This pair of mining wrenches arrived from north of the border today, made by Rastall in Canada, complete with built-in thumb detection and locating systems. One of them is for my brother. It was much cheaper to have them sent together to me, and then send one to my brother via USPS than to have them sent by Canada Post to two different addresses in the US.
What makes them mining wrenches? More precisely, they're mining jack leg rock drill wrenches. A jack leg rock drill has a pneumatic leg that's planted into the bottom (floor) or rib (wall) of a drift or crosscut (tunnel) to drill into the face (end of a drift or crosscut) or into the rib or back (ceiling). The pneumatic leg is attached to the impact drill and drives the drill bit into the rock. Watching a good driller drifting (generally horizontal drilling) or stoping (drilling vertically) is like watching a ballet.
The hole in the handle is a 7/8" 12-point, the most common size of faceted drill bit and the most common size of fastener used on jack leg rock drill couplings, which have both pneumatic and water lines running to the drill. The jaws open wider than a normal 12" to the width of a standard 15" making this lighter on the mining belt. An adjustable wrench should never be used as a hammer, unless one is desperate to detect and locate where their thumb is, having misplaced it while working. This has said device on the opposite side of the fixed jaw. That portion of the head is hardened specifically for use as a hammer, allowing it to be used quite vigorously without damaging the wrench. Partway down the handle on both sides is a 6-inch mark with an arrow. That is the minimum "bootleg" distance for drilling another borehole from a failed one, either from drill (bit) failure, or from charge failure when the explosive charges were fired. The primary use of "bootleg" is a borehole with a failed charge that didn't fire or did not fire completely and is still intact. One must deal with charges that haven't fired and the procedures are something the powder monkeys know how to do. There's an entire heuristic "science" to blasting in underground mining. The charges are timed in rapid sequence to leave nothing more than a pile of muck (rock rubble) to be removed with an underground loader, with minimum dust and zero debris flying around. What you see in the movies is pure fiction.
One of the principals in the Rastall company observed how adjustable wrenches were being used in drift and stope drilling in underground hard rock (mineral) mines in Canada and created the design. Having done underground hard rock copper mining in central Arizona during the misspent halcyon days of my youth, I knew exactly what this wrench was and how it would be used in mining. I was not a driller, but was around them enough to know how it's done.
Amazon sells a couple different mining wrenches like these, which obviously copied the Rastall design, but they're not nearly the quality of Rastall, which is considered the definitive maker of these wrenches. They're excellent quality forgings with very good finishing and assembly, and are popular among the Canadian miners. I wish these were around when I was doing hard rock mining decades ago. Most of us carried 12" or 15" adjustable wrenches.
John
