I should add that things are healing pretty nicely, 3+ weeks after the accident. I should have near-total range of motion and feeling in those digits, which are almost as long as they used to be. The major difference going on is that I won't have much of a thumbnail left, and will have some scarring.
I was tempted to let this sorry incident disappear without blogging it, but my friends at Make717 urged me to document the failure so that others may avoid it. Sigh... hate being the "Don't be that guy" poster child, but perhaps there is some redemption thereby.
Here is the instrument of my doom - a brand-new drawer-lock bit:
It's the old story of being pulled into the router bit when things go wrong. Since the accident I have heard a dozen or more stories from woodworking friends about their similar mishaps, which helps a little, I guess. Here's what I've figured out:
1. FAILURE TO USE PUSH STICKS. Might as well get this one out of the way right away, because I feel SOOOOO stupid about it. There were no less than three different push sticks on the router table while I was making this cut, but in that moment of being focused on the bit and what it was doing, I reached forward with my hand instead of picking up the push stick. Dumb, so let's just agree never to speak of this again, shall we?
2. POOR FENCE SETUP. Like many router tables, my fence has adjustments to bring the fence in as close to the bit as possible, and I had made those adjustments. But with a bit this big, it still leaves a dangerously large gap:
Better is a setup like this, with a custom fence for every type of bit profile. My commitment to myself is that I will always do this from now on. Honestly, I think a fence like this would have prevented or minimized the accident, even with the stupid move in point #1. Sadly, I had already made this fence for a previous job, but just didn't think to install it. Never again.
3. INADEQUATE UNDERSTANDING OF INADEQUATE INSTRUCTIONS. Frankly, I give the Freud tool company part of the blame for this one, because there were no use instructions with this bit. The sole instruction was this, as part of the packaging:
The only dimension they called out, bit height at 33/64", was very specific, and I set that using a digital height gauge. But this is one of those bits that you address from both orientations, so to speak. The front (which their picture has at 3/4" thick) goes across the bit flat on the table , and the side (1/2" thick) is passed by the bit with the workpiece standing on end, guided by the fence.
I was attempting the latter cut in stock that was a full 1/2" thick, and actually was using a wide piece to make the cut "safer" in my mind. But my inadequate understanding of the setup led me to have the fence too far back, making a deeper cut than pictured in the diagram. The joint would actually work that way, but when I found the piece of wood many days later where it was thrown across the room, I realized the nature of the failure - one that might have been avoided with a shallower cut:
As you can see, the piece actually sheared off at the cut. My theory is that, as the end of cut was reached, the workpiece tilted into the large gap in the fence and was dragged back into the bit. The bit basically chewed the workpiece to shreds and threw it off the table.
It also taught me at a much more visceral level something I had read many times: a router will pull you into the bit faster than you can react! In this case, my right hand was at the gap, and the bit threw the work to my right in a few milliseconds. Since I was exerting downward pressure, I basically slammed my hand down into the bit.
4. EXCESSIVE BIT SPEED. Here's another place where I give Freud part blame - they could have so easily put bit speed suggestions on the package. Since I mostly use smaller bits, I had my router set at full speed, and it didn't occur to me to slow it down without some prompting. But I should have, because the cutter speed increased drastically as the bit diameter increases. Not sure if that played in the accident, but it easily could have.
5. HASTE. This is it in a nutshell - all of the above happened because I was in a hurry. I had a little bit of time in the shop, and thought, "I'll try that new bit!" This has been an excessively harsh reminder to slow down and think things through.
When I was doing my Master's work in Choral Conducting at Penn State, I was the assistant conductor of the University Choir with Dr. Tony Leach. In Friday rehearsals, he would often exhort the students to be careful over the weekend, ending with an evocative phrase that I'm going to print, laminate, and hang on the wall behind my router table:
Awesome way to close out this experience! Well documented.
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