Amazing Keychain (with a Bike Chain)




About: Electronic+Mechanical Engineering Student at National University of Colombia. Bike Mechanic and Cyclist

Hi! and welcome to my first Instructable.

Searching on internet about bicycle parts I found this keychain in the comments on the page made me think ... why not do it yourself?

Tools and Materials

  1. Keys
  2. Bike Chain
  3. Chain Rivet Tool
  4. Pressure/Locking Plier
  5. Cutting Tool (Mototool with carbide disk or Jewerly Saw)
  6. Drill with 7/16" Metal drill bit
  7. Abrasive Paper

Warning: this lifehack is not advisable if the key is subjected to a high torque in the lock

Teacher Notes

Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.

Step 1: First, a Little Explanation

The chain is composed of several parts: Outer plates, Inner Plates, Rivets, Rollers. Generally, the chain has a space between rivet and rivet of 1/2 "and depending on the use can vary the width of it. For bicycles with a single speed the roller is wider than a chain for multiple speeds.

For this tutorial, the goal is to replace the rollers with the keys.

Step 2: Organize the Materials

First, dissasembly the chain preventing the rivet from leaving one of the outer plates and separate the parts, select the keys to build the keychain, Keep in mind that the number of keys it's as the number of rollers.

The chain that I used I took the last change of chain of my bicycle, a KMC X10SL chain

Step 3: The First Hole

For precaution, the top of the key is retained and a 7/16 "hole is opened in the center of the key, with a file the hole is adjusted so that the inner plates fit very well. With the help of inner plate the edges are marked

Step 4: Cut the Keys

With the help of a mototool cuts are made to the key, you can also use a jewelry saw or a soft saw.

Step 5: Finish the "rivet"

Using the same mototool, or using jewelery files, the edges of the new rivet are polished so that their size is not greater than the edge of the outer plate. Using abrasive paper softens the edges

Step 6: Keychain Assembly

This part should be done with care, it is sought to reassemble the chain using the keys instead of the rivets, a way to do it quickly is with the help of a clamp of pressure, taking care that the rivet does not deform the outer plate. With the help of the chain tool you can adjust the rivet so that the key can move in the chain

Step 7: Test the Keychain

If the lock is in good condition, and the assembly has been correctly made, the chain will perfectly withstand the torque of the key. To increase this resistance can be used a thicker chain (this one is 5.6mm, 10 speeds) or fix the key in the chain by tightening the outer plates. When the assembly is not performed correctly or when the lock requires additional effort the chain does not resist and disarms

Step 8: ¿Optimize the Keychain?

Performing the instructable I thought, how close can you leave the chain in the key? Then note that the chain edge can serve as a stop for the key. (As the photos show)

Step 9: Same Steps, in to the Limit

To make the same key at the limit of its length, the key is marked with a straight line (marking the stop of the key) and the outer plate is placed as a reference and the same perforation and the same cuts are made as described from step 3

Step 10: Finish and Test the 2nd Version

There is an advantage when making the key this way, as it is much easier to assemble and occupy less space.

As shown in the second image, the chain serves as the limit for the key to fit correctly

Unusual Uses Challenge 2017

Runner Up in the
Unusual Uses Challenge 2017

Be the First to Share


    • Home Decor Contest

      Home Decor Contest
    • Furniture Contest

      Furniture Contest
    • Reuse Contest

      Reuse Contest

    15 Discussions


    2 years ago

    I love the concept... but I worry about the integrity of the key's strength after being reduced so much... can you vouch for the strength of the keys after reducing it so much and after using it for at least a few months continuously?

    Again, great concept! Doubly great if the keys survive as long as a normal unadulterated version is it does as well.

    2 replies

    Reply 2 years ago

    Hi! If the lock is
    in good condition, and it does not take much force to operate it, the
    bronze with which the key is made can withstand that normal deal, now,
    if the force is excessive, it is more likely to disarm the chain (the rivet release the outerplates) to damage the key

    That's why I warned you at the beginning

    Mortimer Wisa_k

    Reply 2 years ago

    Well keys are essentially just specifically shaped pieces of metal, so as long as you don't cut the key any narrower than its connection to the tab, it should hold together. Because, the tab of a key doesn't offer much strength to the key, it's just for the convenience of the user.


    2 years ago

    This is a great idea for just a few keys. I really like it, and I like the looks of it. But I used to have a ring of 10 or so. I can imagine how long that would be.


    2 years ago

    Very cool. Voted.


    2 years ago

    Very nice, thanks for sharing. I'll make one soon

    You got my vote!


    2 years ago

    brilliant and very creative nice work


    2 years ago

    oooohhhh i want to do this!


    2 years ago

    I love this. Very clever!


    2 years ago

    That's an awesome keychain! My nephew would love this :)