Recently my USB drive was stolen, fortunately everything was backed up.
It got me thinking, what if there was sensitive data on it? Or top secret government files?
That is when I came up with this, an USB drive with an physical data lock. With a few switches the no one would be able to access the data. Of course there is already software to secure data, but what is the fun in that.
It is an easy and quick project that requires little skill. I finished it in an hour.
The project is very low cost as well, most parts are already laying around the house.
Step 1: Materials and Tools
For this project I used these materials:
-A marker pen/case
-An USB 2.0 drive (use an cheap one, it might get damaged)
(-Or an USB 3.0 drive, but these are more difficult, because they require more wires/soldering.)
-Small wires (at least 15 cm or 6 inches)
-A few switches (The more switches,the harder it is to crack the code)
And these tools:
-A soldering iron
-A small hobby knife
-A hot glue gun
-A lighter or dremel (optional)
Step 2: Schematics
I have made some simple schematics to make this project more understandable.
I basically took one of the 4 connection pins and I put two switches in between.
When I want to use it both switches should be in the right position. Two possible positions per switch, so there are 4 possible "codes". If one of the switches is not in the right position the usb drive won't function.
The other 3 wires are just extensions from the port to the circuit board.
Step 3: Opening the USB Drive
To open the USB drive you can use you fingers in most cases. You just need to find the split line on the side and pry it open. If this doesn't work you might need a knife to get in between the two parts of the housing.
It is also possible that there are screws hidden under stickers.
Step 4: Disconnecting the Port From the Board
After a few tries I found out that the easiest way to remove the port from the board is to place the port against a solid object, so it won't slide.
Start heating the pins on the circuit board with the soldering iron after it is hot enough to melt new solder. Then take the soldering iron away and directly push the knife under the pins. Try to loosen one pin at a time and work your way from your side to the other side.
After the four pins are loose, there are 2 bigger pins connected to the board on the side. These are not connected to any electronics, so they can be cut or pushed out.
You can push them out by laying the USB port on a slightly raised surface, than use a knife or screwdriver to push the circuit board down while heating the solder with the soldering iron.
Step 5: Soldering
The soldering is quite easy. Just keep 6 (or more) wires with stripped ends ready. You can use a knife for this step.
Now start soldering 1 wire from the top pin on the port to the top pin on the circuit board.
Solder 1 wire from the third pin on the port to the third pin on the board.
And solder 1 wire from the bottom pin on the port to the bottom pin on the board.
Now solder 1 wire from the second pin on the port to the middle pin on one switch.
Solder another wire from the bottom or top pin on the switch to the bottom or top pin on the second switch.
And solder another wire from the middle pin on the second switch to the second pin on the circuit board.*
If you use switches with multiple rows, only use one row, as displayed in the images.
*It is not necessary to use the second pin for the switches, you can use one of the 4 pins, but you always have to connect pin 1 on the port to pin 1 on the circuit board, etc.
Step 6: Making the Case
To make a case for the new USB drive I used an old marker pen, but you can use just about any thing to put it in.
First I opened the marker up in a way that the opening could be used for the usb port. Make sure that you can still put the usb port in a computer.
Next remove the ink reservoir. Use some paper towels, because this can get messy.
When the inside is clean, cut out an opening for the switches. If your case is plastic an hot knife works best. Just hold the knife above the lighter for a few seconds and cut. Alternatively you can use a dremel.
Insert the electronics in the case and secure it with hot glue.
Step 7: Improvements
If you want you can make the drive more secure by adding more switches. Every switch you add makes it harder to crack the code. You can use the same steps and schematics, just add more switches when soldering the second pin.
You can also try other switches, some have more than 2 positions. these make your drive harder to crack.
Good luck and have fun building!!