Hide the USB Drive inside a USB Cable

Finished 1
Holy crap-- somebody just went and TORE MY FREAKING USB CABLE IN 
HALF while it was still attached to my laptop!!!
No-- wait-- sorry. That's just my USB drive. My bad. Never mind.
(And after the jump, how to make your own.)

It's no secret that there are a lot of strange USB devices out there,
particularly flashdrives. Not a comprehensive list, but we've sure seen
Lego, twigs, action figures, bowling balls, sushi, anatomical parts,
transparent driveseraserscassette tapesand on and on and on.
Despite all that, the picture above is a little surprising-- because yes,
 it's a working USB flash drive. Here, we give the step by step walk
through of how to make your own.

Kingmax USB 1 GBExposed pads
IMG_5502.JPGIntended use
This is a KingMax 1 GB USB flash drive, one of the smaller varieties out there.
 I got it on eBay for about $10 and there seem to be plenty more available.
 Above, you can see it in between my fingers and in my computer for scale.
The gold pads are just printed pads on a tiny circuit board.

InsideBare board
The plastic cover is attached only weakly, by a bit of silicone adhesive, and
peels off fairly easily to expose the bare printed circuit board of the flash
drive. Not too much to it, really.

USB cableCable to cut
Cut along seamSplit
Next we need a victim USB cable. I started with this new $1.50 USB "A-B" cable. Looking at the end that we'll be cutting up, you might notice a neat injection molding seam that runs around the edge. Using a sharp hobby knife, cut neatly along that seam. Cutting there actually provides some camouflage for you: Since
we expect there to be a seam there, it's very hard to notice an additional cut as well. If you really want your seams to be invisible, you might want to use a black USB cable. Cut deeply enough that you actually cut through to the metal shell underneath the rubber, at which point you can start to peel back the rubber parts.

The metal shell underneath the rubber overmolding consists of two of pieces
of thin steel that are stamped and folded into place. They are held together by
some tabs and slots-- use a small screwdriver to defeat the tabs and you can
pull the flap the "lid" piece, so that you can now get at the inside of the metal

With the one piece of the metal shell removed, you have access to the middle
parts of the shell where the original USB wires and plastic and metal connections are located. Cut them away with your choice of tools. I found that the hobby
knife worked well enough to sever the wires, at which point the remaining
plastic parts could be removed pretty easily. What's left is just the metal
shell-- ready for us to put our own circuit board in.

Insert board...IMG_5621.JPG
Test fit
Now we can start to test-fit the bare-board USB drive into the metal shell.
 Seems to fit okay. Still need to fix it in place, though. 

InsulateFinal test fit
One other final detail to take care of: The back side, where the circuit board
will be resting, has some metal parts that the back side of the circuit board
will be touching-- so we need an insulator there. I had an old piece of clear
 blue heat-shrink tubing that happened to fit well, but a piece of electrical
tape would have done the job too. Once that was added, it all looked safe
and still fit together.

Grace periodNot yet seated
To bond everything together and fill all the extra space inside the USB cable
end, I use gel-style 5 minute epoxy. Fortunately, five minutes gives you
enough time to apply the glue, place the flash drive in place, and put the
rubber molded housing back on. Hold the connector firmly-- paying attention
to the seams for alignment-- until the epoxy cures, about five more minutes.
Finished 3
Last step: Cut the cable as desired. A jagged cut looks different than a
clean cut-- take your pick.



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