Sometimes when you need light in the dark it is very inconvenient to carry a flashlight, so you wear a headlamp, which is quite good for its job but isn't very "stylish" :) to wear in public. Using this instructable you can learn how to build a handy and "stylish" hat-lamp that is barely even noticeable until you turn it on.
Step 1: Materials That You Will Need
-battery (maxell CR2016 3v +)
-two LEDs (5mm high brightness white)
-strip of cardboard (about 2 in. by 3/4 in.)
-baseball cap (probably not your favorite one unless you don't mind cutting it up)
-thread (probably as close as you can get to the color of your hat unless you don't care if it doesn't match
Step 2: Put the LEDs on the Cardboard
1)First put four holes in the cardboard strip using your sewing needle (the pictures below will help you to know where to put the holes). The holes don't have to be in any exact position, but make sure that each set of holes has enough space in between the set to fit the LEDs legs without bending them and putting stress on them.
2)Put your two LEDs in their positions with both identical sized legs facing the same direction, either right or left (this is just so you know which ones to wire together in future steps even when it is hard to tell their sizes after they are bent).
3)Bend your LEDs so the bulb part sticks over the edge of the cardboard and the legs stick straight out the bottom (again, pictures are below).
Step 3: Wiring the LEDs
1) Cut four pieces of wire 2 1/2 to 3 in. Strip both ends of each of the wires.
2) Twist all four wires on to all four legs of the LEDs (try to twist them tightly but gently because you don't want the LED legs to break).
3) Wrap each connection in a small amount of electrical tape to avoid short circuiting.
4) take the wires that are connected to both of the long LED legs and twist them together, do the same with the short wires.
Step 4: Connecting the Switch
1) Slightly untwist either one of the twisted together wires connected to the LEDs.
2) Put it through the hole in any of the legs on the switch (at this point it doesn't matter which one).
3) Wrap electrical tape around the connection.
4) Cut a slightly shorter wire than the other ones and strip it on both ends.
5) Twist one end of the shorter wire into a leg on the switch that is next to the last wire.
6) Wrap electrical tape around the connection.
Step 5: Connecting the Battery
1) Take the positive wire or the negative wire from the LEDs depending on which one you connected to the switch and press it to the positive side of the battery (if it's positive) or the negative side of the battery (if it's negative).
2) Put one end of a two inch long piece of electrical tape on top of the wire and battery.
3) Find the short wire that is attached to the switch and take the end of that wire and press it to the other side of the battery.
3) Wrap the two inch long piece of electrical tape all the way around the battery and all the wires attached to the battery.
Step 6: Turning It On
If the lights did not turn on when you connected the battery you might need to slide the switch to the other side. The switch should be on the side that the two wires are on.
Step 7: Putting It in the Hat
1) Cut a slit on the seam in the bill of the hat about four inches long. Try to just cut the stitches instead of the actual fabric.
2) If the hat has more stitches in the middle of the bill cut those also.
3) Put the LED circuit in the hat with LEDs pointing out the front of the bill.
4) Feel where the switch is underneath the fabric and make a mark there.
5) Cut a small hole in the fabric where your mark is.
6) Put the LED circuit back in the hat the same way as before and stick the sliding part of the switch through the hole you made.
Step 8: Sewing It All Up
1) Thread the thread through the needle and tie a knot at the end of the thread. Stitch through the cloth and the metal hole in the switch on both sides of the switch. Tie a knot in the thread when you are all done to keep it from becoming undone.
2) Thread another piece of string into the needle and sew up the front of the hat and tie a knot at the end.
3) When it is all stitched up slide the switch over to the on side and put your hat on. Wait till night and try your hat out while your reading a book or something.