Break it Down: A lock with brains

The August Smart Lock is an excellent example of today's technology enhancing a centuries-old device. Its clean design makes it easy to install, and its wealth of handy features are simple to use. The technology is useful, yet unobtrusive.

And this lock is no dummy, with a 32-bit ARM Cortex MCU, Bluetooth system-on-chip, eight LEDs and even a microspeaker. Controlling it all is August's app, which lets you manage digital keys, lock and unlock it via your smartphone, and even automatically lock or unlock your door when you get close.That's a lot of tech packed into the August's 3.25-inch-by-nearly-2.25-inch cylindrical body alongside the motor and gears needed to turn a deadbolt.

Disassembling the August Smart Lock

Unlike most of the gadgets and gizmos I crack open (such as the Samsung Gear Fit featured in the Winter 2014 edition of CNET Magazine), the August doesn't require special tools for disassembly. I began my project by removing the lock's faceplate, batteries and a pair of stickers from the back cover. One of the stickers was hiding a screw. Sneaky. I then used a standard Phillips screwdriver to remove the four external screws that hold the lock together.

Once the screws were out, I lifted the back cover away from the lock body. A small speaker is attached to the back cover, and I had to disconnect its wire before completely removing the plastic cover. Next, I removed the large metal ring, which also serves as the lock's outer shell. With the back cover and ring out, the August's internal components were easily accessible.

After removing a thin internal ring (a support for the metal outer ring), I very carefully removed the lock's drive gears and their pins. To ensure I could easily put each gear back in the proper spot during reassembly, we took pictures throughout the removal process.

The last component to come out was the circuit board and drive motor assembly. The whole teardown process took less than 30 minutes -- quick by my Cracking Open standards.

What the teardown tells us

Minimalist design, both inside and out: There isn't much to see on the outside of the August. The clean, uncluttered design helps the lock blend into the background.

The same efficiency and simplicity extend to the inside. You can disassemble the lock quickly with standard tools, the parts are easily accessible, and there isn't much empty space inside the body.

• A good balance: August's designers did a good job blending metal and plastic parts. Parts that need to be strong and take the most wear, like the outer ring, gears and locking clamps, are metal while other components, like the front faceplate and back cover, are plastic to save weight. The August is well built and feels sturdy. The outer ring and gears move smoothly as you turn them, but the lock isn't heavy or cumbersome.
• Replaceable components (sort of): Many of the August's components, such as the outer turning ring, inner support ring, gears, back cover and even the tiny speaker, can be individually replaced. Unfortunately, the brains and muscle of the unit can't. The motor and drive assembly are basically one solid piece that's soldered to the main circuit board. Likewise a second, triangular circuit board, which holds the notification LEDs, is also soldered to the main board. If the motor burns out or one of the board components fails, you would need to replace the whole unit or break out your soldering gun.
• Plenty of tech inside, with one noticeable exception: August has lots of tech, minus a Wi-Fi chip. Why? Because Wi-Fi drains batteries. By sidestep-ping it, August claims that the lock's four AA batteries should last a year.

A leap in the right direction

I was impressed by what I found inside the August Smart Lock. Is it perfect? No. Lack of Wi-Fi is a limitation. The need to use four AA batteries means the body is larger than it need be.

In the end, the lock is only as smart as the app that controls it. And, as Executive Editor Rich Brown wrote in the CNET review , "From the free e-keys and logical user management to the reliable automated lock and unlock settings, this lock can legitimately make a small element of your life easier." Easier is good.

This story appears in the summer edition of CNET Magazine. For other magazine stories, go here.