Volkswagen 4GB USB Flipkey for My MK2




I thought to myself: "Hey, I've got this Volkswagen Flipkey laying around. Let's see about cramming a 4GB USB drive in it". The one thing I did not want is to see the USB sticking out of the key. I wanted to keep it original looking.

I thought about trying to fit my retractable Cruzer drive, but upon further inspection, decided that it would be a huge challenge, plus I wanted to keep it original looking when closed. I happen to have a male - male USB cable that a friend gave me. This is why I went with the female USB connector here.

For this Instructable, I have already knocked out the laser side-cut key that went to my friend's new Beetle. I used a the key for my 1991 VW Golf and trimmed it to fit in this Flipkey.

Additionally, I was at a big box retailer and found a Kingston 4GB Micro SD w/ USB adapter. The USB was normally $25 - Marked down to $14.90. Add to that a $10 mail-in rebate - this whole project cost on the order of $5.00.

If you have to purchase the Flipkey or a USB, your costs will vary.
On with the Instructable.

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Step 1: Getting the Pieces Together

You will need the following items:

Volkswagen Flipkey
Micro SD card with USB adapter - I used a Kingston MBLY/4GBKR
A male USB connector
A female USB connector
4 wires or 4-wire ribbon cable
Dremel tool - Very handy!
Exacto knife
Low-Temp soldering iron and solder
Super glue
Baking soda - Trust me on this!

Step 2: Getting Started

First, take the key apart.
Use a pulling and bending motion to separate the two parts of the key.

Set the key half aside and open the electronics part. It is snap fitted together. The easiest way to get it apart is by using your two index fingers to pry it open where the tip of the key would rest when closed.

Once open, remove the electronics, battery, and battery clip.
Notice the tactile switches on the circuit board.... keepers?
Lift off the red rubber panic button and set it aside.

Step 3: Dremel Your Way to Happiness

Use a Dremel tool to remove excess plastic innards from the flip key.
Look at the USB adapter, it has a raised lid on one side. Dremel into the bottom half of the housing some to make room for this. Visualize the thing together and you can imagine where to remove material to make it fit.

Carefully measure and remove material where the Panic button was. This is where you will install a female USB connector. Go slow so you don't make the opening too big.
Frequently test fit your female USB in the opening to make sure you get a good fit.

On the top half of the housing, push the alarm buttons in as much as possible and trim off the 3 inside portions that protrude into the housing. These contacted the tactile switches originally. This will keep the buttons from interfering with the innards later. Trimming these tabs will not affect how the buttons feel from the outside.

Step 4: Fixin' Up the Micro SD

I took a male USB and remove the metal housing. I also used my Dremel to sand the top portion at an angle to take up less room in the bottom of the housing.

Mate the Micro SD housing to a male USB. I took the male USB apart, only keeping the white inside part. Connect it to the Micro SD adapter housing and test the fit in the key housing.

Step 5: Need a Little More Room...

I tested the fit and it still did not want to snap together.
I peered down the inside as I held the two housings together. I noticed that if I trimmed the female USB housing down, it was going to fit.

I took the Dremel tool and cut off just the top portion of the housing. Then I sanded down the white plastic portion a bit to make the fit.

Step 6: Solder Up the USB's

Lay out the Micro SD adapter, the Female USB, and the stripped male USB.
When you lay this out, make sure you always flip one piece over the other. Don't twist.
This is difficult to describe. Worst case scenario is that your computer will not recognize the drive and you will have to resolder after reversing your wiring.

After soldering, slip the stripped male USB through the USB opening first, followed by the female USB in its final place.

Glue the female USB in place using the good ol' baking soda trick. Glue both sides and get some underneath it. Cover liberally with baking soda and pack it in with a small screwdriver. Dump and blow off the excess baking soda.

Step 7: Making the Fit

It took me several attempts to get this to fit. It will be close. If it does not fit, you can remove more material in the bottom of the housing.
*I decided against it, but you could remove the plastic cover from the micro SD adapter by cutting or sanding. I wanted to keep this intact in case I ever wanted to do something else with the adapter.
A little more work on the bottom of the housing or the female USB will make the fit.

If you see daylight through the bottom of the housing - you went too far!

Step 8: FINAL ASSEMBLY, (Then Show N' Tell!)

Once you get the USB housing fitting nicely, you can connect it back up to the key.

Next, replace the red panic button over the USB opening to serve as a dust cover.
Mine took a small amount of trimming to compensate for the metal of the USB sticking up around the edges of the opening.

I thought I'd try placing the panic dust cover under the closed key for safe keeping while the USB was in use and replacing it to cover the USB when not in use.


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    16 Discussions


    Reply 9 years ago on Introduction

    Pretty easy. Take your VW MK2 key to a locksmith. I recommend getting a fresh code-cut key (versus using a worn out key to start this project, a code cut key costs about $18)
    Buy a MK2 Key with a metal head only - no plastic!
    Next, partially open the flip key and knock out the pin that secures the laser-cut key in place (Use a tap hammer and a small drill bit or something to tap it out - keep the pin!!!!)
    Compare the laser key to your MK2 key, line them up and etch a trace around the laser cut key onto the MK2 key.
    Now, take that to a grinder and go to town, get close and finish with files until the MK2 key and the laser cut key bases look the same. Test fit.
    Next, notice that the laser cut key has a vertical notch where that pin would line up and hold it for the flipkey. Using the edge of a file, make a shallow notch on the MK2 key that matches the laser cut key.
    Reinsert the pin using needle-nose pliers and a small tap hammer. Test, it should work great!

    The alternative is to cheat and buy a pre-fab VW HAA keyblank that will fit the flipkey. Check out - Will run you about $20 w/ shipping

    If you make it yourself, you have something to brag about! Good luck!

    Project Dryan97128

    Reply 8 years ago on Introduction


    The EuroVan, during the Mk4 years, also got the switchblade key, but still utilized the AH style locks. That is the specific application of the HAA blank for those trying to find it, Eurovan 2000 thru 2003 (at least in U.S. production).

    Hope this helps open some people's options!


    Reply 9 years ago on Introduction

    ooH, ok cool man thanks a lot!. I never noticed that there was a pin holding the key blade on there. I thought the key and they moving part was all one piece, I will definitely be doing this soon.
    by the way what MK2 do you have?


    Reply 9 years ago on Introduction

    A 1991 VW Golf.
    Check it out:


    Reply 9 years ago on Introduction

    whoa that's a pretty wicked system you got there. Those cross-hairs look pretty good too.


    Reply 9 years ago on Introduction

    Thanks, I bought it for $600 at a police auction, then I lowered and tinted it, put the wheels and badgeless grill/headlights on, stereo, etc. Lots of lookers


    10 years ago on Step 8

    I don't know what I just looked at...but it was very interesting. I am now going to hide all my electrical the way I'm missing my VW key did I leave it at your house? Love Mom

    2 replies

    10 years ago on Introduction

    hello this was a very cool project I made two of the one with a 16 gb flash drive and one with a card reader and a 16 gb transflash card, but I used a micro usb female instead of a reg sized usb sorry for the photo my camera is old wtserg


    10 years ago on Introduction

    could you somehow replace the key with a usb drive so when u press the key release button the usb drive flips out?

    1 reply

    Reply 10 years ago on Introduction

    Due to the mechanics of this keyfob, it does not look like one could easily do that. With that said, someone could probably re-engineer the fob. For myself though, I use this as my car key, so I wanted to keep that function. If you decide to take on the task of a flip-out USB connection, I want to see it!! Thanks


    10 years ago on Introduction

    Nice work, the clever soldering definitely make the final thing look more professional than having a usb plug sticking out all the time!

    1 reply