Introduction: Friendly Folding Keychain

So ever since I can remember I have haaaated carrying keys. They're uncomfortable sitting in your pockets all day, they make it hard to find change when you need it, they scratch up everything around them, be it cell phones, cameras, etc.. and when you really think about it, your standard keychain is really just a terrible design. Why would you subject yourself to that? Well I've decided enough is enough and set out to make what I think is a much more friendly and functional keychain. My criteria for this new design are as follows:

- Compact and foldable
- Comfortable in the pocket
- Easy to distinguish from all other possible pocket contents
- Not rough or abrasive
- Aesthetically pleasing
- No jingling!

Step 1: Crank Brothers M5 Multitool...

I found this great little Crank Brothers M5 Tool that was the perfect start. It is designed for cyclists and as such is very lightweight. Not only would it be the perfect housing for my keys, but it also sported a variety of allen wrenches and a philips head screwdriver as well. Sweet! If that wasn't motivation enough, it was cheap at only 12 bucks!

Step 2: Take It All Apart...

The first real step was to take the M5 apart and see what kind of tolerances I would be working with and how everything was going to fit together. I ended up adding a couple flat washers to make up for the space differences between the allen wrenches I removed and the keys I added.

I was pleased to find that your standard house and car keys are the perfect length to fit snugly inside the folded M5, so you don't have to worry about adjusting the position of the keyholes. The only part of my keys that really required any modification at all were the little square holes. I imagine there are key blanks out there that have a large enough hole to work right out of the box with no modification at all, but alas, I would had to make my square keys fit a round peg.

Step 3: Make Sure the Keys Fit...

Time to grab my trusty metal file and go to work. After I had filed proper size holes into all three keys (2 house keys and one car key) all that was left was to put everything together and admire my work.

Step 4: File Away the Excess Key Bits...

I could have just left it at that but I'm picky and didn't like how much the outside edges of the keys poked out on each side. So, once again, I grabbed my file and went to town re-shaping the exteriors of the key. Normally you would want this wide part on a key to provide proper leverage when turning the lock, but since my keys would be firmly attached to a larger piece this wasn't a concern.

I filed each key down until it had a nice rounded shape. I also opted to file a little corner into each key so that I could easily flip them out with just the tip of my thumb.

Step 5: Ta-Da!

Ta Da! All folded up it measures about 3.5" x 1.25" x .75" For reference, you could fit two of them inside the footprint of a credit card. I wanted mine to be as small as possible, but if you didn't care about a small form factor, or you needed room to accommodate more keys you could always go with the Crank Brothers M-10 which is the same length as the M-5 but twice as fat.