THW

M Fournier: I have cut damp PT wood (copper rich) on my SawStop. It does not set off the brake. The saw is very well thought out. If something is almost conductive enough to set off the brake, then the saw will shut down without setting off the brake, signaling that you need to make that cut in bypass mode. If you have material that you suspect might be too wet, you can make a cut with the saw in bypass mode, and the saw will signal whether it would have set off the brake. If it wouldn't have, you can make the rest of your cuts in protected mode; if it would have, make the rest of your cuts also in by-pass mode. It's a matter of turning a key on the side of the switch as you start the saw. As several have said, you would need to be cutting wood that was dripping wet to make the saw fire the brake. That's pretty rare, and you'd surely know you were in a situation that was worth running a by-pass mode test.

I have a SawStop saw. The primary reason to buy one is that it's an excellent saw: solid, precise, smooth, accurate. I have not tested and do not intend to test the blade brake feature, but I know a good many woodworkers with years of experience who have cut themselves on their saws. None of them intended to, but all of them spent substantially more on medical bills than the $200 it takes to replace the blade and brake cartridge, and several of them couldn't work with their injured hand or fingers for weeks. Each of them could tell you what they might have/should have done to avoid the injury, but obviously that knowledge didn't prevent the injury.

The questions that people are raising about the saw here are readily answered on the web site for the saw and by understanding the technology. The saw measures the capacitance of the blade and releases the blade brake when that changes in a way that the circuits recognize as characteristic of the capacitance of a human body.

It will cut wet wood: it would take VERY wet wood to activate the brake, but there's a by-pass key that allows you to cut even aluminum, though obviously without the SawStop protection during that cut (it returns automatically to protected mode each time you shut off the saw). The steak-on-plywood scenario is like wet wood: the capacitance of an electrically isolated steak is not a great enough change to activate the blade. The capacitance of an electrically isolated human body, even a small body, is much greater than that of a steak, enough to activate the brake. As I understand it, even a piece of metal embedded in the wood will not activate the brake UNLESS the metal also touches the table at the same time that it touches the blade, which is unlikely since the large table insert is phenolic; it would have to be a very large piece of metal to touch both.

The web site and the manual make clear that the saw will almost always injure you to activate: dry skin is not an excellent conductor. The blade is stopped and dropped below the surface of the table in milliseconds, which in practical terms means within the rotation of five teeth of the saw (look at the pictures of the blade in the brake after activation). So the blade will break the skin, but not much more. Thus, if you're wearing gloves, it will cut through the glove to your skin, nick your finger, then stop, much more quickly than you can read this sentence.

Skeptics keep imagining scenarios in which you could do yourself serious damage, and SawStop certainly does not and could not guarantee that you won't. If you had the blade raised to its full height, reached your hand up to turn on a light just as your dog rushed up to leap on you from behind so that your hand dropped precipitously onto the blade, I imagine you would get more than a nick (though a lot less than if you had another saw). The point is that doing the things that one does hundreds and thousands of times with a table saw, with your hand moving at the speed that it is generally moving when you are feeding wood into the saw, you should be protected from anything bigger than what you might need a BandAid for.