Flashlight Business Card




If you have read my other business card instructables, you will know what this is all about - make a business card that is useful, or that people really don't want to throw away, and you have a successful piece of advertising. This is a variation on my previous flashlight card, but made to look a bit more flash, and to be easier to construct - no PCB needed for this one - just some self-adhesive copper tape. The finished design costs less than a dollar to make, and they are simple enough to make up a small batch of these in an hour or two.

Step 1: What You Need

  • One CR2032 battery (I got them for about 16 cents on ebay when I bought 100)
  • Two blank PVC ID cards (Again, I got these for about 16 cents - find a specialised ID card printing store on the web near you - I used www.digitalid.co.uk)
  • One 3mm High-intensity white LED (Ebay again! I got 100 for about $16, so 16 cents each again!)
  • Some double-sided foam adhesive tape (I got mine from an office supply store for a couple of dollars - you just need tape that is thicker than the battery you are using - mine was 4.5mm thick)
  • Some self-adhesive copper tape (Ebay! Mine cost a few dollars for a long roll of 1 inch thick tape, and I cut it into thinner strips, but you could also buy the thinner version)

You will also need a soldering iron (plus solder), a cutting knife, some spray adhesive, and a way of printing the front of your card - you can use a colour laser or inkjet. I printed on paper and laminated it, but have had success before with printing in reverse on OHP transparency film which can look good as well.

Step 2:

Cut a couple of strips of copper tape about 1/4 inch wide and 2 1/2 inches long. Solder one end of the LED to one of the copper strips, starting about half way down the lead of the LED. Make the connection so that the soldering joint is close to the edge of the copper strip, and dont use too much heat, or the selfadhesive backing paper peels off. Then turn the LED over, and do the same on the other side.

Step 3: Attaching to the Card

One of the leads of the LED will be longer than the other - this will connect to the positive of the battery. Peel off the backing of the copper strip attached to this one, and apply to the middle of one of the blank ID cards. Try and get it so that the LED is poking out just a little from the edge of the card.

Step 4: Attaching the Foam Tape

Apply some self adhesive foam tape around the perimeter of the card, and also around the battery to stop it moving. Make sure that the unattached copper strip is free to go above the battery - it does not need to be stuck to anything.

Step 5: Attaching the Overlay

Design the layout of your card on the computer, and print out - I just printed on plain paper and then laminated it. You might will want the image to be a little bigger than the card (called a "bleed"), so that you can cut it exactly to size later, and not have a white boarder around it. Spray some adhesive on the back of the printout, and attach it to the unused ID card. Then turn the card over, and cut neatly around the outside of the card. Finally, attach this ID card to the front of the electronic assembly.

Step 6: Changes

If you are making a few of these, you can ditch the double sided tape and use foam sheeting, attached with self adhesive spray. By using one of the blank cards as a template and cutting out around the outside, you can get a neater edge on the finished design. You can then just cut holes for the battery, and LED, making sure there is a vertical cut halfway down the card for the top copper strip to poke through. You might also want to fix the LED a bit more securely so that it doesn't get knocked around in use. A blob of 5 minute epoxy does this job well, and is transparent as well.

If I produced these on mass, I would probably change a couple of things. Firstly I would change the CR2032 cell to a CR2016 as this is thinner, and also design a custom self-adhesive foam cut-out for the LED and battery to replace the double sided tape. Getting the cards printed professionally would then allow the cards to be assembled in seconds each, rather than minutes. If anyone is interested in getting commercial versions of this card or another design produced for corporate use in quantity, I can be contacted at info@lightboxtechnology.com. (Or if you want to give your kids a really great time next summer, check out the Tech Camp!)



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    26 Discussions


    6 years ago on Step 6

    Wouldn't the copper tape hit the battery while in a pocket, causing it to stay on even when you don't want it to?

    1 reply

    Reply 6 years ago on Step 6

    The foam is thicker than the battery so it doesn't work unless you've squeezed it. I see from your other comment that you've found the UV version which is a later (and simpler) version of the same basic design that doesn't need soldering so I would recommend it over this older instructable - you can of course still choose any colour LED you want.


    9 years ago on Introduction

    cool i like am am going to make one for my dad bisness
    ( i am a bad speller haha)
    good job :)


    9 years ago on Step 6

    nice, its getting rarer and rarer to find creative people in today's culture. but your definatly one of them! (i know i cant spell definatly right :) )


    10 years ago on Introduction

    Decided to spruse up works giftcards... So much better... (Don't worry, just mucking around. Not showing them either. Just for personal fun.)

    2 replies

    Reply 10 years ago on Introduction

    i read that they have like credit cards and stuff that can do all sorts of things now --- wireless payment, fingerprint reader......................


    10 years ago on Step 6

    I'd just like to say that I really enjoy your business card Instructables. They are creative and unique. Thanks for the ideas.


    10 years ago on Introduction

    I have started a parts box not too long ago and I found a CR2032 battery in it O_O I have two of them cause in the picture when I seen the back of it i am just like Hey.... I think I have a battery like that!


    Reply 10 years ago on Introduction

    This design is self-limiting - with the voltage drop of the LED comparable to the cell voltage, as the current drawn increases, so does the voltage drop of the LED, limiting the current to around 10-15mA tops (LEDs are generally rated for around 20mA). You would need a resistor If you replaced it with just about any other colour (maybe with the exception of blue, which has a high drop as well). The disadvantage is that the light is not very bright, but it won't burn out. If you want a bright version, add a second cell in series, and stick in a resistor.


    Smart idea. Dont count on that card being thrown in the other pile of business cards.