Sunday, September 10, 2017

The Workbench, Part 3

Building the bench top was a long, tedious process. First, because the pallet boards were anything but straight, I had to test-fit each board against the preceding board in four possible orientations to find the best fit. Then I drilled pilot holes for the screws. Because the whole point of this massive top was to have a rigid base for mounting the lathe and other machine tools and the boards were 1.25" thick, I used 2.5" screws. This meant I had to stagger the screw locations to prevent the point one screw from running into the head of another.

I used two drills, one to drill the holes, and the other to drive the screws with a driver bit. In the foreground is a "sled" a movable work surface to set tools and materials on. It's a scrap of particle board with short lengths of 2x4 screwed to the underside on each end to keep it from sliding off the boards it rests on. It was especially helpful in the early stages of the process, when I hadn't built enough of the top to set anything on.
I had meant to take more pictures of this process, but it was so mind-numbingly boring, that I forgot. I wore out my drill bit early on. I had extra bits in a few common sizes, but not the right size for these screws. I thought I'd just buy a multi-pack of that size, which was how I'd acquired the spares I had, but nobody seemed to carry the size I needed, except in a complete set. I had actually bought a bench grinder and extra bits several months before, intending to practice sharpening them, but I couldn't master the physical skill. The bits always came out worse than when I started.

I had wanted to try the Drill Doctor, but I hated to spend the money not knowing what results to expect. Reading the reviews, everyone seemed to love it or hate it. I noted that most of the people who hated it were skilled machinists who said it might be good enough if you were drilling wood, but they preferred a precision-ground point when drilling metal, and they could get better results freehand with a bench or pedestal grinder. The Drill Doctor 350X was $55 on Amazon, about the price of 2 sets of bits. At the rate I was wearing them out, if it worked, it would pay for itself on this project.

I placed my order, and it arrived with amazing speed. After reading the instructions it took only a few minutes to get the technique down and produce a point far better than I had ever managed to grind by hand. Is the point exactly like new? No, and a skilled machinist could probably do better. But the lips are exactly equal, the included angle is exactly 118 degrees, and the relief is pretty darn close to the optimal 8 to 12 degrees. We'll see how well it works for drilling metal when I build my lathe, but for now, more than 90 percent of the holes I drill are in wood, and this machine turns a bit that won't drill wood into one that will. Pallet wood wears out bits quickly, and more than once I ruined a point by drilling into a screw. The Drill Doctor has already paid for itself in bit sizes that are not sold separately, not to mention trips to the hardware store.

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