While the high operating efficiency impact rammer is fundamentally a dirt tool, its role in municipal asphalt repair is crucial. When a water main breaks in the middle of a city street, we have to saw-cut the asphalt, excavate, fix the pipe, and then patch the road. The "throw and roll" method—dumping cold patch asphalt into a hole and letting vehicle traffic pack it down—is a recipe for a massive pothole in two weeks.
To do a permanent utility cut repair, I use the jumping jack on the base layers of the asphalt. However, running a steel shoe on sticky, hot-mix asphalt (HMA) or aggressive cold-patch is tricky. The bitumen binds to the bottom of the shoe; within minutes, you are lifting a five-pound pancake of asphalt with every stroke, throwing the machine completely out of balance. To combat this, we use dedicated water kits or constantly spray the bottom of the shoe with an environmentally safe release agent. The trick is to hit the edges of the cut first. I run the rammer tight against the vertical saw-cut face of the old asphalt, pinching the new mix against the old road to create a watertight seam. Then, I work my way to the center. The sheer percussive force of the rammer achieves a density in the patch that a small vibratory plate simply cannot match, ensuring the repair survives the winter snowplows.
