G'day Lenny, SawStop LLC is a company formed to develop and market improved active safety technology for woodworking equipment. They say, "Our goal is to make woodworking equipment better and safer for the user. SawStop was started by Stephen Gass after he invented the SawStop technology. Steve is a lifelong woodworker with a doctorate in physics, which puts him in a unique position to develop the SawStop technology. The SawStop 10" cabinet saw was developed from the ground up with a particular focus on safety and quality. It features a revolutionary safety system that stops and retracts the blade (within 5 milliseconds) upon accidental contact, drastically reducing the severity of user injury. The safety system provides invisible protection (doesn't interfere with your work), is always "on" and performs continuous self tests. The saw also includes a European style riving knife (secured via a quick-change mount) that helps minimize kick-back.
SawStop Saws are the most advanced saws in the world. Each saw is equipped with a safety system that detects when someone accidentally contacts the spinning saw blade, and then stops the blade in milliseconds. In most cases, such an accident would result in just a minor nick on a SawStop saw , instead of the devastating injury which would likely occur on an ordinary saw. The photo at the right shows what happens on a SawStop saw when a hotdog (representing a finger) hits the spinning blade at a speed of about 1 foot per second. The SawStop safety system includes an electronic detection system that detects when a person contacts the blade. The system induces an electrical signal onto the blade and then monitors that signal for changes. The human body has a relatively large inherent electrical capacitance and conductivity which cause the signal to drop when a person contacts the blade. When the detection system sees dips like these, it knows a person has touched the blade. A fast-acting brake stops the blade when contact is detected. The brake includes a heavy-duty spring to push a block of aluminum, called a brake pawl, into the teeth of the blade to stop the blade from spinning. The spring is held in compression by a fuse wire until contact is detected. When contact is detected, the system sends a surge of electricity through the fuse wire to burn the wire and release the spring. The spring pushes the brake pawl into the teeth of the spinning blade, and the teeth cut into the aluminum and bind, thereby stopping the blade. All this happens in about 3-5 milliseconds, or 1/200th of a second. At the same time, the angular momentum of the blade causes the blade to retract below the table and the power to the motor is shut off." For more info: http://www.sawstop.com/about.htm There are a couple of amazing online video's on this Web Site which are really worth a listen! John Melbourne Australia. From: Lenny McHugh To: Handyman-Blind Sent: Friday, September 21, 2007 12:50 AM Subject: [BlindHandyMan] totally safe power saw Hi All, A few years ago on hgtv Ron Hazelton had a home improvement program. Occasionally he would show some new products. He had a man who had a totally safe power saw and was trying to get someone to manufacture it. It worked on the same principal as plaster cast cutting saws, that is where he got the idea. Instead of the blade making complete revolutions it had very short reciprocating motions. If it came in contact with your fingers the skin would move and maybe receive a minor cut but your fingers would not be detached. He cut a lot of hardwoods and from the description it did a great job. I have been patiently awaiting for such a product. Has anyone heard of such a product? I did write to Ron Hazelton but never received an answer. Lenny http://www.geocities.com/lenny_mchugh/
