Picture of RJ-45 key chain and rack
This Instructable will show you how to make a cool colorful key chain and a rack for storing those key chains out of RJ-45 jacks and plugs.
Remove these adsRemove these ads by Signing Up

Step 1: Materials

Picture of Materials
there are two parts to this instructable.
the first part is the key chain, in order to make the key chain you will need the following:

1. RJ-45 plug crimper
2. cutting or sleeving tool
3. scissors

1. 2 pair or more network cable
2. RJ-45 plugs (male)
3. colored rubber protector for RJ-45 plug
4. key ring

the second part is the rack for the key chain. it is optional. in order to make the rack you will need the following:

1. depending on the type of wall and the type of mount.

materials : 
1. wall mounted box for RJ-45 jacks
2. RJ-45 jacks (female)

Step 2: Key chain step 1 : disassembling and cutting the cable

Picture of key chain step 1 : disassembling and cutting the cable
the standard network cable consist of multiple parts, the only two parts we will be using are the insulation and the wires (4 wires to be exact).

disassemble the cable, identify the parts and keep the parts mentioned above.

the minimum length of cable we can use is 10cm because that gives a little tail popping out of the rubber protection. you may use more if you want a longer tail.

choose the color of wires you want and cut them to the desired length.

Step 3: Key chain step 2 : final preparations and assembly

Picture of key chain step 2 : final preparations and assembly
take the 4 wires and fold them down the middle to form a U shape.

order the colored wires however you like.

using a pair of scissors cut the tip of the wires in a straight line.

gently insert the wires into the RJ-45 plug. be careful not to mess up the order.

while holding the wires in and making sure they reach the very end of the plug crimp the plug using the crimping tool.

check the wires are in place and not coming out.

cut about 3cm of insulation and insert the folded wires into it, then push it as far as it will go into the plug.

put the rubber protection over the wires and plug.

insert the key ring into the loop created by the folded wires.

Step 4: Rack step 1 : assembly

Picture of rack step 1 : assembly
well, this part is pretty straight forward.

most wall mounts will include the RJ-45 jacks built-in, if not just put them in yourself - its just a couple of clicks.

make sure the jack is sturdy enough. the jack will get connected and disconnected many times, this is not regular use, regularly you would connect a cable once or twice in a relatively long period of time.

mount the box(es) on the wall.

Step 5: Final thoughts

i recommend tagging the ports so you know which key goes where
you can also use flags to tag the keys
if you have different colored rubber protectors you could color-code the keys and divide them into groups by type or location of the lock they open.

« Previous41-57 of 57
harari (author)  rbarone23 years ago
There are crimper tools for 1$ in eBay (metal not plastic)
and 10 jacks for 2$

check out DealExtreme.com too.
Very cool idea for us geeks. Thanks
tqwerty3 years ago
Great idea!
cbatchelor3 years ago
I can see it using scrape cabling, an old patch panel, and free space on a rack for a key box.
Lindie3 years ago
Cool idea!
headdezoysa3 years ago
its looks like WIRELESS KEY!!!!!!!!!
Exocetid3 years ago
You need to sell these. Just a clever and imaginative idea. I could see these in the ThinkGeek catalog!
chamunks3 years ago
THIS ... IS .... Awesome!

How about you find a way to integrate a small LED and wire it a bit logically so that it can also double as a simple Continuity tester?
Mark AJA3 years ago
Many years ago I saw in an electronic magazine using a jack plug as a key.
A different resistor connected across the two pins was used.
If the correct resistance was read and did not change for a second or two then the electronic lock was opened.
The timed delay was used to not open if a variable resister was used.
Brad I.3 years ago
Love it! A great idea for organizing all the server keys I have to keep up with.
przem3 years ago
Nice and geeky idea :-)

I think this can be also used as a simple electronic coded key. By connecting the pairs of pins inside RJ plug in different combinations you can code several different keys. Then some circuit to interpret the code and there you go :-)
dodland3 years ago
Pretty cool idea! I like how one uses snagless cable, especially since they go in your pocket. Could also build a shelf with an old unmanaged 5 or 8-port hub or switch laying around.
crapflinger3 years ago
extra extra points if you make it an ethernet loopback at the same time, then you can take down people's layer 2 switches whenever you like
mrmath3 years ago
Pretty cool idea that could easily be implemented in a data center or some other such place. Extra points for geekiness are scored if used at home. Just a nice idea. Two thumbs up!
harari (author)  mrmath3 years ago
This was actually implemented at a server farm where i used to work (still being used today - should have put my name on it...). i don't use this at home but a couple of ex-co-workers walk around with similar key chains on their house keys (just for show, they don't have the rack at home)
jefersonrod3 years ago
very cool, nice.
matbh3 years ago
what a nice idea!!! i really enjoy it!
« Previous41-57 of 57