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Excerpted with permission from Ready the Cannons! Build Wiffle Ball Launchers, Beverage Bottle Bazookas, Hydro Swivel Guns, and Other Artisanal Artillery by William Gurstelle (Chicago Review Press) © 2017 by William Gurstelle
Excerpted with permission from Ready the Cannons! Build Wiffle Ball Launchers, Beverage Bottle Bazookas, Hydro Swivel Guns, and Other Artisanal Artillery by William Gurstelle (Chicago Review Press) © 2017 by William Gurstelle

Science marches forward but not always in the direction we want it to go. Sometimes things get invented that, really, I wish were not. Choosing the “worst invention of the century” is a pretty subjective exercise no matter how you go about it. Still, some ideas are just terrible no matter how you look at them.

First, take the 20th century’s worst idea: the baby nuke.

During the dark days of the Cold War, nuclear war meant one thing — mass devastation on a scale so horrific that the mere thought of it normally stops the conversation right there. But in the middle of the 20th century, U.S. Army war planners hit on the idea of waging small-scale, limited nuclear war. Thus was born the idea for something called “tactical” nuclear weapons.

The first artillery-based nuclear weapon was the M65 cannon. Nicknamed Atomic Annie, this weapons system fired a 15-kiloton shell about 7 miles. Soon after Annie’s inception, an even smaller nuclear cannon was developed.

Figure A. Worst 20th-century invention: Battlefield nuclear weapons
Figure A. Worst 20th-century invention:
Battlefield nuclear weapons

Code-named Davy Crockett, the small weapons system consisted of a recoilless rifle and small, portable nuclear shell (Figure A). In my opinion, Davy was a terrible rendition of a terrible idea on many levels. The nuclear payload would destroy most everything within a half mile of where it landed and release a cloud of deadly radioactivity in the process. Since the rifle had a maximum range of only about 3 miles, the gunners were bound to get a good dose of radiation themselves, especially if the wind was blowing their way.

Worse, it’s not hard to imagine that if one side used a small nuke, then the other side would respond in similar fashion. After a few rounds of retaliation and counterretaliation, the big ICBMs would likely start flying, after which cockroaches and tardigrades would emerge as the dominant species on the planet. So that’s why I think tactical nukes are the worst idea ever.

OK, enough with the serious stuff. The second worst invention of the 20th century is the leaf blower (Figure B).

Figure B. Second-worst 20th-century invention: Leaf blowers
Figure B. Second-worst 20th-century invention: Leaf blowers

Your local home center has lots of gas- and electric-powered outdoor machines that really can make your life better. While I can’t say I love my lawnmower or snow blower, they do serve important purposes. But the leaf blower? Like the Davy Crockett, it’s something that should have never been invented. To subjectively paraphrase Shakespeare, a noisy, consumer-grade leaf blower is a device used “by an idiot, full of sound and fury, and that does almost nothing.”

My former neighbor Big Pete loved his leaf blower. For him, any time was leaf blower time. Instead of using a rake or broom to clean up his yard, he’d joyfully shoulder up his leaf blower and spend a merry hour or two shattering the neighborhood peace with a 100-decibel roar, doing a job that could have likely been done in half the time with a manual tool.

Not only that, these breathtakingly irrational wasters of energy are highly polluting. The typical leaf blower’s tiny and primitive two-stroke gas engine (in which oil is dumped directly into the fuel tank and from there, spewed into the atmosphere) puts out more pollutants per minute than a 3-ton Ford pickup truck, and has a carbon footprint 30 times greater. It’s true that electric leaf blowers are less polluting than gas-powered ones, but they’re still noisy and, in my opinion, they work poorly when compared to a regular garden rake.

So is there any reason on Earth for a leaf blower to exist? Surprisingly, yes. It makes a terrific Wiffle Ball Launcher.

The Wiffle Ball Launcher will accurately (by Wiffle ball standards) pitch ball after ball for games or practice. Made from $25 of plumbing supplies, some scrap wood, and your leaf blower, this project shows off your DIY chops to their best advantage. A key component is an easy-to-find PVC plastic fitting called a “low heel inlet elbow.”

By a miraculous quirk of fate, the 3″×3″×2″ low heel inlet elbow couldn’t be better for turning your leaf blower into a Wiffle ball pitching machine. First, it accepts a 3″ diameter PVC pipe, which is the optimum-diameter barrel for a regulation Wiffle ball. Second, the 2″ inlet matches up exactly with most round leaf blower nozzles.

But here’s the magical part: because of the fitting’s geometry and a fluid mechanics principle called Bernoulli’s Law (see my Remaking History column “Giovanni Venturi and the Venturi Effect”), an object like a Wiffle ball inserted in the top of the fitting will be sucked in and shot out the barrel.

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Project Steps

1.

Drill two ⅛”-diameter holes and insert the small screw eyes into the thick part of the low heel inlet, as shown in Figure C.

Figure C
Figure C

2.

Refer to the Wiffle Ball Launcher Assembly diagram below during the remaining steps. Attach the 10-foot-long, 3″-diameter PVC pipe to the 3″ horizontal opening on the low heel inlet. Don’t reduce the length of the barrel because a short barrel won’t provide as much range or velocity.

leafblow
Click for larger version.

3.

Attach the 18″-long, 3″-diameter loading tube to the 3″ vertical opening on the low heel inlet.

4.

Place the barrel, loading tube, and low heel inlet assembly on the sawhorses. Center the assembly and rotate it so the loading tube is vertical. Attach bungee cords from the sawhorses to the screw eyes to hold the loading tube vertical.

5.

Some leaf blower nozzles fit well into the 2″ opening on the low-heel inlet. If yours fits, skip ahead to Step 6. If not, insert the 4″-long, 2″-diameter pipe into the 2″ hole on the low heel inlet and use reducing fittings as necessary to make it fit.

6.

Align the nozzle of your leaf blower with the 2″-diameter pipe on the low heel inlet. Use duct tape to securely seal the connection (Figure D). You’re ready to go.

Figure D
Figure D

BATTER UP!

Turn on the leaf blower, insert the Wiffle balls in the loading tube, and watch them shoot out. My shooting chronograph shows a muzzle velocity of about 50mph using my moderately powerful leaf blower. You can elevate the barrel with wood blocks to adjust the trajectory of the ball into the strike zone. Because of the Wiffle ball’s holes, each pitch will flutter and curve, making the batting challenge extra fun.

Most leaf blowers don’t produce enough power to propel a Wiffle ball with a high enough velocity to be really dangerous. Still, Wiffle ball trajectories are erratic by design, so be aware you’ll frequently get hit by a pitch. Wear a batter’s helmet and eye protection.

VICTORY THROUGH AIR POWER

lukens-air-rifle

girandoni_air_rifle
Two different air rifles, by Isaiah Lukens (top) and Bartholomäus Girandoni (bottom), believed to have been carried by Capt. Meriwether Lewis on the Corps of Discovery’s expedition of 1804–1806.

Air guns, in one form or another, have been around for thousands of years — much longer than gunpowder weapons. If you think about it, blowguns are a type of air gun that has been used for hunting since prehistoric times.

The use of mechanically powered air guns goes a long way back as well. The first were simply blowguns powered by a bellows attached to the breech. Instead of huffing into the pipe, some clever large-game hunter came up with the notion of putting a squeezable bag on the end. When the bag was squeezed, the compressed air shot a dart or pellet out of the gun. And if the bag was squeezed using the mechanical advantage derived from a system of levers (imagine a fireplace bellows), then the gun could be made to shoot much more powerfully than could be accomplished through lung power alone.

The oldest existing mechanical air gun is thought to be a specimen in the collection of the Livrustkammaren museum in Stockholm, Sweden. Inside this old gun, which the museum dates to about 1580, a spring mechanism operated an air bellows located in the stock of the gun. When the shooter pulled the trigger, the spring caused the bellows to force a powerful air gush that shot a specially shaped bolt, or dart, toward the target.

By roughly 1600, air-powered darts were being shot for sport across Europe, in a variety of ways. According to the people who study such arcana, spring-powered air guns activated by a moving piston (which was a big improvement upon the earlier bellows-reservoir technology) quickly appeared. An early, exceptionally detailed description of such an air gun is found in the Elemens d’Artillerie by David Rivaut, who was preceptor to Louis XIII of France. He ascribes the invention to a man identified only as “Marin, a burgher of Lisieux,” who presented the first air gun to England’s Henry IV. By the turn of the 19th century, air guns had developed to the point where they were likely more accurate and more powerful than black powder weapons of similar size.

Circa 1800, air guns of any size and quality were frightfully expensive to make. It took months of time, arcane knowledge, and excellent tools to make a device of this type because the components — valves, locks, cylinders, and reservoirs — had to be very carefully machined. Consequently, an air gun cost far more than a simple black powder rifle and was beyond what most people of the time could spend on a sporting piece.

But for those who could afford them, air guns offered a lot of advantages. By comparison with a smoothbore, muzzle-loading musket, air guns were a hunter’s dream. For one thing, they could be fired several times a minute, far more readily than the muskets of those days, which required a load-tamp-fire procedure.

Second, they didn’t emit any smoke. This made it easier to aim the next shot if it was needed; line of vision wasn’t obscured by powder smoke. Third, a shooter didn’t need to be concerned about keeping his powder dry; it worked as well in damp weather as in dry.

Probably the most famous air gun in American history was a rifle carried by Meriwether Lewis during the Lewis and Clark expedition of 1803–1806. The actual gun may reside (there is controversy surrounding its pedigree) in the Virginia Military Institute’s museum of historical weapons. The VMI museum claims that the .31″ caliber, flintlock-style pneumatic rifle in its collection is the one built by expert clockmaker Isaiah Lukens in Philadelphia and hauled to the Columbia River Valley and back by the Corps of Discovery. But recent scholarship suggests Lewis carried a Girandoni air rifle, an Austrian repeater that could empty its 20-ball magazine in 1 minute. In either case, Lewis’ air rifle demonstrations astonished the Native American tribes they met along their epic journey.