Building your own external hard drive is easy, and it allows you to choose all of your own parts, giving you control over capacity (disk space), interfaces (such as USB3 or eSATA), size, power requirements, and case styling. We’ll break the steps into three categories: choosing your requirements, shopping, and assembly.

Build Your Own External Hard Drive: Requirements

There are several things you can customize about your drive, but most of them come with trade-offs. For example, a physically small drive will probably cost more than an equivalent physically-larger drive. Here’s a list of things to consider:

• Capacity: how much storage space do you need? The more capacity, the higher the price of the drive. Also, above a certain number (which keeps changing), a very high capacity drive forces you to use a magnetic drive rather than a solid state drive.
• Type: traditional magnetic drives are cheaper per gigabyte than newer solid state drives, but solid state drives are faster and sometimes use less power. Solid state drives are also a little bit more resistant to damage from being dropped.
• Power: small drives can often be powered using a single USB connection, so you don’t need any extra cords. Other drives require two USB connections—one for power and one for data. High-capacity drives will often require a separate power cord which needs to be plugged into the wall, making these drives less portable.
• Interface: if all the computers you plan to use the drive with support USB3, that’s currently the best option to use. Older computers may support eSATA, so if you plan to use those older computers, make sure you get a drive enclosure with eSATA support.

Building An External Hard Drive From An Old Hard Drive

If you have an old hard drive lying around the house, it is easy to turn this into an external hard drive. After all, external hard drives are only hard drives in external cases. There is absolutely nothing special about them. But here are a few tips if using an old hard drive:

1. Older hard drives could use different connections like IDE instead of SATA so take note. You will have to buy an external box to suit.
2. Older hard drives might not have a large capacity. I know I still have 20gb hard drives lying around my house. Now days they are very small when it comes to storage space.
3. An old hard drive might be nearing the end of its life.
4. A used hard drive might have old files of photos that you might delete if you use.
5. You might not know the history of the old hard drive and sometimes it is better to start off fresh.

Build Your Own External Hard Drive: Shopping

Once you’ve decided on your requirements, it’s time to go shopping for the parts you need: a drive, an enclosure, a data cord, and (if necessary) a power cord. You may also want an optional case to keep your drive protected in your backpack.

The drive you’ll buy will be an internal hard drive—you’ll convert it into an external hard drive by putting it in an enclosure. All consumer internal hard drives these days have a SATA connection, which is what you’ll need. Some people see all the parts you need and resort to buying a ready made external hard drive, but bare with us and you’ll see how easy this is.

Look for a drive that meets your requirements for capacity, type, and power. If you decided on a single-USB cord for both data and power, you may need to buy a pre-built drive, as low-power USB drives are not generally available as internal drives.

The main choice you’ll be faced with is whether to by a 2.5-inch or 3.5-inch drive. The smaller 2.5-inches will typically work with a two-USB cord power/data connection but tend to cost more per gigabyte. The larger 3.5-inch may require a separate power cord that gets plugged into the wall, but they can currently provide up to several terabytes of data storage.

Once you select a particular drive, choose a drive enclosure. The main thing you need to know about the enclosure is its size so you can ensure that it matches the size of the drive you chose. Next, look at its data connections—USB3, eSATA, or (on older enclosures) USB2. Make sure it supports the interface you plan to use.

Look at the drive’s power interface to make sure it matches your requirements. If it’s a 3.5-inch drive enclosure that requires wall power, make sure the enclosure comes with a power adapter (or you know where to buy one).

The last thing to look at for the enclosure is its appearance—there are lots of enclosures to choose from, so choose one that you like. (Or, if you like crafts, choose a plain one you can decorate yourself.)

Finally, add the necessary cords to your shopping cart. Some enclosures come with all the cords you need; others just include the enclosure. You always need a data cord (USB3 or eSATA) and you may need a power cord (USB or wall adapter). When buying a data cord for USB, make sure it’s a USB3 cord—a USB2 cord (which are currently the most common) will give you much slower USB2 speeds.

If you decided to buy a case, you can shop for that now also. Remember to get a case that fits the size drive you have, and also remember that you’ll probably have to carry cords with you to use the drive, so you may want to buy a case with an outside zippered pocket to store the necessary cords.

Build Your Own External Hard Drive: Assembly

After all that work outlining your requirements and finding compatible parts, you’d think assembly would be really difficult—but it’s not. Read the instructions for your enclosure, put your hard drive in the enclosure, seal the enclosure (usually requires a screwdriver), and you’re done. Just connect the external hard drive to your computer and (if necessary) format it by right-clicking on its icon and clicking on Format in the menu. See how to format an external hard drive.

Conclusion

Building your own external hard drive is all about defining your requirements and making sure you buy compatible parts—so make sure that when you add parts to your shopping cart, they’re really compatible. (Or that the shop you buy from has a good return policy in case you make a mistake.) The actual assembly is so easy that anyone can do it.