Drills and Gimlets

In the mid-nineteenth century, the advent of malleable cast iron put into workmen's hands mechanisms that once existed only in great windmills. Each turn of the large gear on the hand drill gives multiple turns of the smaller gear and its attached drill bit. An increase in speed is always made at the cost of torque, but the difference in the size of the circle described by the hand crank and the diameter of the drill more than compensates for this.

Many drills also have a smaller driving gear concentric within the larger one to use with larger diameter bits. Larger bits also need more pressure and a steadier bearing to keep their broader cutting edges shearing the wood or metal beneath them. The breast plate on heavy-duty hand drills lets you employ the mass of your body, freeing one hand to hold a side handle while the other hand turns the crank.

Reciprocating drills such as bow drills, pump drills, and push drills that work on an Archimedean spiral do well in a narrower range of the density-to-diameter continuum. In other words, they bog down in softer wood and lack the torque for larger holes. But when it comes to making pilot holes for small screws, I'll reach for the push drill or the bradawl. This last is a tool like a sharpened screwdriver that is first pushed in across the grain and then twisted to push the severed fibers away.

On the business end, straight-fluted and spiral bits are much the same, two shearing edges radiating in a conical point. The same pattern that drilled rivet holes in Henry VIII's armor helps you hang a curtain rod today.

Then there are gimlets. Who looks on their gimlets with affection? You may not appreciate the speed and ease of a hand drill until you have had to put a few miles on a gimlet boring holes for a pegged shingle roof. No more than a T-handle on a small drill bit, they are a nuisance to sharpen, easily broken, kill your arm, and split the wood. Other than that, they're great.

Gimlets come in various configurations, most often screw-pointed with either a crescent moon or spiral-fluted cross section. They cut on the sides as well as at the point, and any re-sharpening has to be confined to the interior hollow. A scraper ground from the hard edge of a file will do, as will a round slipstone. I've read that you can sharpen spiral-fluted gimlets by boring a hole with the gimlet, putting oil and emery powder in the hole, and then turning the gimlet back and forth within it. I don't know anyone who bothers.

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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