Introduction: Zip Triggered Bag Light
Stop feeling for stuff inside you bag/purse in the dark ! instead follow the instructions below to add this mini LED lamp inside your bag to spot exactly what you are looking for..
You don't need to be an electronic genius to build this project as it includes basic stuff that you can get at your electronic/hardware store, but you need have basic sewing skills.
Based on the size of the bag this should take you about 1 hour 30 mins to make.
Step 1: Things You'll Need
Here are the items you'll need for the build
-Bag/purse with the zip made of a metallic slider and teeth made of plastic
- sewing needle
- normal sewing thread
- velcro straps
- super Glue
- flexible plastic which you can find as part of toy packaging or Shirt collar plastic stay
- super bright white LEDs
- conductive thread
- jewelry pins(has two parts that is pin end and the snap), i think you should be able to use safety pins instead
- 2 AAA batteries
-bread boarding hookup wire
- power source to power the LED, here are a few options, choose the appropriate one based on the size of your bag/purse.
- battery holder for 2AAA batteries
- coin cell.
- Lipo battery for small bags
Step 2: Planing - Deciding What Goes Where
Using a pencil or a crayon sketch out which components goes where, basically you'll need to decide
#1 where you will place you battery holder with the LEDs
#2 decide which zip, if you have multiple zips you will have to select one to trigger the lamp
Once your done with the above, you will need to measure approximate distance between the zip and the battery holder .Cut a piece of hookup wire, remember to add 3 cms to your measurement to accommodate for soldering.
Note: Ensure that zip of the bag that you plan to use to trigger the light is made up of a metallic slider and the teeth are made of plastic, as shown in the next step.
Step 3: Basic LED Zip Test
Before you get any further , it is a good idea to check if you zip is metallic and conductive enough to light up the LED's, do a quick test by following the instructions below
Load up the 2 AAA batteries in the battery folder
Check if the Led lights up when you connect the Red wire(+ve terminal) from the battery folder to the longest leg of the LED and black wire(-ve terminal) to the shorter end of the LED, this means the LED is working.
Now connect the LED short end and black wire using two finger, touch the longer end of the LED on one side of the Zip slider and the red wire from the battery holder to the other end. If the LED lights up it means you are good to proceed ..
Step 4: Soldering LEDs,Wire and Snaps
Connect two high brightness white LED's in parallel, that is the two long end (+ve terminal) and the two short ends together.
Connect the battery holder red wire to long end and black to the shot end, check that both LEDs light up.
Fire up the soldering iron and solder only the black wire to the short end of the two LEDs.
Once done solder the red wire from the battery holder to one metallic snap .
Solder the other wire that you cut as part of Step 2 to the other metallic snap and other end to the Longer legs of the 2 LED's, as shown in the picture.
Once done validate that the LED's glow once you touch both the snaps together.
Note: Depending on the size of your bag and the brightness of your LED you can decide to go with one LED.
Step 5: Raising the Zipper's Bottom Stop - Creating the Trigger
Now that you have all your electronics components ready to go lets work on the bottom stop of the zipper from where your circuit will get triggered.
For a quick test, and to get a feel of where the snaps need to be pined and the distance between them, so that the slider can make contact, pin them and with the batteries in the battery holder run a quick test to check if the LEDs light up.
Now once you are satisfied with the distance between the snaps ,cut out a piece of flexible hard plastic from the packaging of a toy or cut a plastic shirt collar stay. You'll need two pieces, one for the inner and other for the outer side of the bag.
Insert the pin end of the Jewelry Pin into flexible hard plastic and insert it just above the bottom stop of the zipper as shown in the picture and insert the other plastic piece on the inner side of the bag.
Note: Plastic piece's are added for strength, so that there is NO contact between the snap when the zipper is closed and your on the move !
Step 6: Sewing With Conductive Thread
For a couple of days,I used my zipper triggered bag light without out the need for Conductive thread, to find out that the LED's would not light up because of a loose connection.This is when conductive thread from RadioShack came handy !
Using conductive thread,needle and pliers if required . Sew 1.5 cms above the newly installed custom bottom stopper to the pin.
Also as shown in the picture a great tip is to take the thread under the hard plastic and around pin for a better connection.
Once done do a quick test as show in the video.
Step 7: Adding Super Glue
Once you are done with sewing , apply super glue to the under side of the plastic and let it dry for about 5-7 minutes.
Also apply super glue below the outside hard plastic where ever possible and let it it dry for another 5-7 minutes.
Step 8: Super Glue Velcro to the Battery Pack
Super Glue Velcro to the battery pack lid and let it dry for about 5-7 mins..
I managed to salvage velcro from an old winter glove.
Step 9: Adding Velcro Inside of the Bag and Sewing
Depending upon where you plan to place your battery holder you can either sew the velcro to the bag or use super glue..
Sew both the red wires to the side of the bag, using normal sewing thread as show in the picture.Here don't sew the wire end to end as we will need to get/replace the batteries.
Pull the battery holder off the base , pop open the lid, insert the 2 AAA batteries and you are good to go!!
Step 10: Safety Tips
Here are a few safety tips
- use electrical tape over the snaps inside the bad and pins outside the bag to prevent the lamp from being triggered when the bag is placed across a metallic table/chair
- if your bag gets wet in the rain, get the batteries out of the battery holder and leave it to dry.