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.

This is the homemade riving knife I had made for our Rockwell Unisaw. I was unable to located the original owners manual anywhere in the office or the shop, but found a digital copy of the original owners manual for this saw on OWWM.com and discovered that this saw originally came with a riving knife! Unfortunately for me, it was probably lost somewhere along the way. I called a local tool retailer and asked them if they could order me a replacement one. The guy on the other line said he could but it was going to cost me about half as much as a brand new saw: $500! Instead I walked to the machine shop next door and asked them if they could help me out and one hour later I had a homemade riving knife in my hand, cut from scrap steel, costing a total of $0!

Here is a picture of the installed riving knife.

Here is a shot of what it looks like while a board is being cut. The riving knife prevents the board from clamping down on the blade, thus preventing kickback and injury.

The second safety feature I installed, or more appropriately, had installed for me, was an emergency off button for the table saw. Many woodworkers hang a board down in front of the on/off buttons that, when kicked, hits the off button and turns the saw off. I didn’t like that (it seemed like it would come with it’s own safety risks), so I had an electrician install a large round button close to the ground that is easily kicked if the user needs to shut of the saw for any reason.

From now on things should be a bit safer around here!

Jared Patchin started woodworking professionally in 2008 when he set-up  J.Alexander Fine Woodworking in Boise, ID, where he builds custom crafted furniture and cabinetry.