Micro-Shaving Procedures
Introduction
Micro-shaving or micro-blasting, as it is sometimes called, is a method of removing rock in small
manageable portions. The principle behind its success involves the detonation of a small charge
(blank .22 cartridges) deep in a predrilled hole. Not only is the immediate area of the detonation
affected, but will often shatter and send fracture lines radiating from the point of impact. With the aid
of a chisel, additional rock can be chiseled off in a safe and controlled manner. When used properly,
micro-shaving is extremely safe.
Who uses micro-shaving?
Many folks have enjoyed the pleasure of safe rock removal. Our micro-shaving kits are in use by
Search and Rescue teams, commercial cave owners (for trail modification), geologists, excavators,
contractors and caving expeditions. In fact, if you have ever seen “too tight” on a cave map, this
may give you a new option to extend that map.
First things First
Wear Proper clothing
• Long pants
• Gloves
• Long Sleeve shirt or Jacket
• Goggles for eye protection (provided in our kit)
During detonation, rock shards may be blown off with enough force to strike nearby objects. Users
should always protect themselves from getting hit by rock fragments when possible, however good
protection can be easily achieved by wearing the proper clothing.
Tools you will need
Your micro-shaving kit has everything you need to break rock except a hammer drill. Be sure you have a charged battery and a working hammer drill.
Included in this kit:
• Micro-Shaving Rod Assembly
• Spare Detonating Rod
• 5/16” x 6” SDS Drill Bit
• Power loads in waterproof bottle
• 1/2” cold chisel
• Safety goggles
• 8” Safety pad
• Hammer
• Blow tube
• Cinch bag
• and, of course, these instructions
You will need to provide:
• Hammer Drill with a charged battery
• Proper clothing and gloves
• A rock in need of removal!
Placing the hole
Drill your 5/16" hole about 3-4" from the edge to be removed. Drill
in solid rock - not in a preexisting crack. Drill to the full depth of the
drill bit (approxima
tely 4"). DANGER! Drilling a shallow hole will
result in small rock pieces flying in every direction. A 4"
deep hole will dislodge nice 3-4" chunks of rock and
reduce small shrapnel.
Do not bear down on the hammer drill. Let the natural
weight of the drill determine the force used by the
operator. If drilling against gravity attempt to provide about
12 pounds of pressure to the hammer drill while drilling.
Cleaning the hole
To clean the hole, FIRST put your safety goggles on. Place one end of the blow tube in the drilled
hole, the other end in your mouth, and stand to the side. Blowing hard while moving the tube up and
down in the hole will remove most of the dust. Polishing with a hole brush is important if placing a
bolt, but unnecessary for micro-shaving.
Placing the load
Shake one or two loads from the waterproof bottle. Two will provide the maximum safe charge.
CAUTION! - Never use more than 2 loads and NEVER use 22 caliber live bullets. Delicate rock
removals can be achieved using just one load per charge. Drop the load(s) into the hole - crimped
end facing the bottom and the rim facing the top of the hole. If the load(s) falls into the hole upside
down there should be no significant difference in the detonation.
Detonating the load
• Prior to detonation, verify that all safety gear (gloves, goggles, etc.) are in place.
• Place the detonating rod through the middle hole of the blasting pad.
• Place the detonating rod into the drilled hole.
•
Thread your hand through the detonating rod lanyard.
• Securely grip the detonating rod handle.
• Using a moderate blow, strike the end of the detonating rod with
the hammer. A firearm hammer strikes the back of a bullet with
only a moderate force. That same force is all the that is
required to detonate the load(s).
• If the load does not fire, it may be a dud and an additional load can be added if only one had
been originally placed.
NEVER place more than two loads in a hole or attempt to drill out the load(s). Drill a new hole!
NEVER use the spare detonating rod without its handle!
NEVER use the drill bit as a detonating rod!
Finishing the job
After detonation, chunks of rock will roll aside and you can now see new cracks and fractures. With
the supplied hammer and chisel it is easy to remove additional rock. Repeat as needed.
Replacing the Micro-shaving Rod
On occasion the rod of the micro-shaver may be caught in the rock. By removing the lanyard from
the micro-shaver and inserting the supplied spare rod as a T-handle, you can often extract it from the
rock. Should this not be enough, unscrew the rod from the handle and replace it with the spare.
Drilling a nearby hole and detonating another power load should allow the first rod to be extracted.