Not the kind in Terminator or the Matrix. But the ones that some of us might have presented in our first science fair. That is, if you, like me, were passing through grade school at some point in the ’70s – Simple machines.
Simply put, a machine is anything that makes work easier. And a “simple machine” is defined as any device that requires the application of just one force to perform work. While Wikipedia reminds us that there is in fact some contention about this, it is traditionally accepted that there are a total of six simple machines.
The six simple machines are: The Inclined Plane, the Wheel & Axle, the Lever, the Pulley, the Wedge and the Screw. And chances are at least one example of each exists somewhere in or around your house.
Simple Machines in the Home
Here are some popular examples of Simple Machines in the Home:
- Inclined Plane – A ramp, for example a wheelchair ramp. Paired inclined planes make a pitched roof.
- Wheel & Axle – On lawnmowers and wheelbarrow. Also, found in cabinet door glides and on appliances. Another common example – door knobs and even inside those locksets.
- Lever – The bottle opener. Tools – the crowbar, and scissors or pliers. Double Levers – a door, a toilet seat, a broom.
- Pulley – Old wood windows, some garage doors, workshop or garage lifting systems.
- Wedge – The shim – used throughout the home in construction. For example, when installing doors, windows, cabinets, etc. Sometimes used to level furniture or chairs.
- Screw – Like the wedge, above, well, you couldn’t build a house without screws. Certain types of plumbing valves. Plus, a jar lid is a popular example.
Now for deeper look at the simple machines found around our homes.
* The Inclined Plane
The most common example of an inclined plane is the simple ramp. But chances are, unless your house is wheelchair-accessible, you will not find a ramp in it.
My mother’s boyfriend recently capped a set of deck stairs with a ramp constructed of plywood, and covered with exterior-grade carpet. Though not the most aesthetically pleasing, it sure makes life easy for my mom’s aging canine. She, the dog, simply glides down and curses back up when she is done with her business.
If you have ever moved yourself, you probably couldn’t have done it without a ramp. Most moving trucks have a that large metal ramp that pulls out from and stows beneath the truck’s bed. Further, if you have ever visited a construction site, building in progress, you might have noticed the temporary stairs. OSHA probably doesn’t love it, but you’ll find a 2×12, angled from ground to the entrance. It provides a runner for quick entry.
In terms of your house, it is common to see two planes placed back to back. The roof, though maybe not the truest example, certainly has an incline. And unless you live in a contemporary, your roof probably pitches. The pitch allows the roof, with little effort, to shed rainwater. On a much smaller scale, think of a knife as two inclines set back to back. You use them when you are cutting bread or insulation.
You likely have one or more ceiling fans hanging in your house. The blades of these things, tilted at an angle, do a wonderful job with cutting through and moving air. Also, think of some of the surfaces on the outside of your house. When done correctly, your exterior porches and sills (door & window) should have a slight pitch outward. This incline (or decline) allows gravity to do its thing on any water that should find its way to these surfaces.
* The Wheel & Axle
I guess it would be silly if I went into a dissertation on the wheel. I mean, in my eyes, the wheel has to be one of the most significant inventions in all of human history. Without it, would over-land transportation be possible? Ok, you got me with the helicopter (uses inclined planes by the way.) But that is not the point of this article.
Including the obvious lawnmower and wheelbarrow, you find wheels all over your house. They appear in cabinet drawer glides, on the bottom of your refrigerator, on your vacuum cleaner, and in sliding/pocket door hardware assemblies. In each case, the wheel makes movement possible.
This may get overlooked, but a doorknob is just a wheel rotating on an axle. Even if you have leversets on your exterior doors, or fancy lever-handled doorknobs, the internal mechanism usually consists of some sort of axle rotating, retracting the strike and allowing for opening of the door.
* The Lever
Basically, a lever, with its partner the fulcrum, assists in movement. There are three types of levers, each represented in your home.
The most recognizable lever has to be the see-saw. I am not certain how many people have see-saws in their yards; they do require space and can be dangerous with younger children. So we’ll look elsewhere for examples of the lever.
First, there are the levers you might guess: the bottle opener, the crowbar, and scissors or pliers. The last two are “double levers” and are all tools. Then, there are the ones you might not guess: how about a door, a toilet seat, a broom and even your arm or your jaw. Nowhere near as exciting as the wheel, the level is still tough to imagine living without.
* The Pulley
The pulley is probably the most sophisticated of all our simple machines, and it, coincidentally, is the hardest one to provide examples for. Car guys will tell you pulleys are used in several places in automobile engines. But us house guys have to admit, much less popular in the house.
Unless you have older wood windows, there is a good chance that your house currently contains no pulleys. Pulleys work with rope or chain in extension ladders and are helpful when transporting material up several levels of scaffolding.
That’s it; that’s all I got. I will say, however, that I am currently consulting on a project in Fells Point, Baltimore. We were looking for ways to make it easier to lift heavier things up to the third floor though a narrow attic access. I suggested, in the spirit of the watermen that built those houses, a rope and pulley system.
* The Wedge
Of this bunch, the wedge might have the most reason to be thankful. Defined as a moveable inclined plane, does it really deserve its own category? All doubts aside, it is treated with the same respect as the rest.
– The Shim
The wedge separates or supports two objects. And stopping there, this section is dedicated exclusively to the carpenter’s good friend and go-to, the shim – an example of a wedge. Especially if you live in a newer home, and since paired shims have become standard building practice with door and window installations, chances are, your house contains them.
Shims have so many practical uses, it is hard to imagine the end of the examples I could provide. The most common shim is probably the white cedar shake. Industrious types and seasoned carpenters make their own. And for you, there might be more than one occasion when it is a good idea to make one of a scrap piece of pressure-treated lumber. (Note to self: Good idea for a how-to).
A shim can be made out of something as simple as a scrap piece of cardboard or an old playing card. Carpenters use them to change the angle on their miter saws just that discretely. For me, I find these machines indispensable. When trying to make a small adjustment to a door, a window, or a mitered corner, nothing works better than a piece of cardboard. It is recycling & it is usually free.
* The Screw
The screw is a mechanical device that. . . Just kidding. I won’t even go into it here. To be quite frank, I feel it desires its own homage. So that why we produced the guide – Household Guide to Common Screws.
Six Simple Machines
You may be sitting there scratching your head wondering why you read through this blather. Why even write a piece about simple machines? None of this information is really quite practical. It couldn’t be used for a 3rd grader’s research report.
Well, I guess I am of the thinking that by understanding the parts, the elemental mechanics of a system, it helps in demystifying the system. And while the goal is always a complete system, in its whole, it is best if you know that this system, our house, is equal only to the handful of, often simple, simple as 2nd grade, parts that come together to assemble it.
Maybe for you the simple machines unlock some hidden memory that gets you inspired. Or maybe it might help you work smarter, at least more aware, on your next home project.
For more relatively useful info (but some our Best), please visit our etc top level category. Thanks for reading. ~jb