A near-miss on a table saw accident got Jared Patchin at J. Alexander Fine Woodworking to think long and hard about saw and shop safety. Here's his recount of what happened in 2008, and how it lead him to change his woodshop. This is reposted with permission from Patchin's blog
Safety is very important! Woodworking is not the safest thing to do all day everyday. In just about every step of the construction process there is a chance to smash, cut, slice, and grind your fingers. I plan on building custom furniture for a very long time, and I plan on dying with all ten fingers intact.
The reason I mention the safety thing is because we had a bit of a scare at work today.
Sometimes wood does weird things when you cut into it. While cutting a board today, the cut-off side began curving back into the saw blade – essentially sandwiching the blade between the two pieces of board! The blade whined under the increased pressure, the wood smoked as the friction built up, and my mind raced wildly as I tried not to panic.
It is amazing how fast your mind can think when it is stressed. In a split second I had three distinct thoughts:
1. I scolded myself for being so careless. The table saw is an incredibly useful tool for cutting wood. It is also an incredibly useful tool for throwing wood around and for slicing flesh.
2. I felt the blade heat up, saw it wobble, saw smoke as the friction increased, and wondered how the heck I was going to extricate myself from the mess I was in.
3. I vowed to install two safety features as soon as this ordeal was over.
I knew that I couldn’t let go of the board for fear that the blade would catch it, bounce it up, and send wood and metal flying everywhere, but I needed to turn the saw OFF! I held the board as steadily as possible and yelled to a coworker to turn it off, which he was able to do.
Once the blade had stopped, I thanked God for not teaching me a lesson the hard way, and assessed the damage. The blade was scalding hot from the friction, dull as a butter knife, and probably too warped to be used again. The board sported some fancy burn marks.
As noted above, I decided after this little scare, that it was time to install a few safety features on our 30+ year-old table saw. The first and, in many woodworker’s opinions, the most critical safety feature on a table saw is the riving knife. A riving knife is a piece of metal, the same thickness as the blade, that sits directly behind the blade. It prevents the material that is passing through the blade from clamping down on the blade itself (as happened to me). The riving knife ends up being the thing that gets squeezed if a board was to tweak during cutting, and this allows the blade to continue spinning away unimpeded.