You saw Batman Begins, you've now seen The Dark Knight, and now go on admit it, you want one of those mega spotlights with which Commissioner Gordon summons the help of the Caped Crusader. But you don't have a gigawatt three phase power supply, all you have is a measly little 5V USB... don't despair, that's plenty to work with, and if you follow this instructable you'll be casting the most wicked bat shaped shadows all over your bedroom, living room and office walls.

It's dead easy if you have even the most basic making skills and great to try if you've never done any electronics before. Plus there's a little bit of fun hacking apart a Series A USB plug and using the guts!

You'll need

A couple of old packaging bottle caps (shower bottle and single serving drinks bottle, or something similar)
Some thick tin foil (take out tray, or aluminum roofing / flashing tape) although thin foil will work
A cheap USB Laptop light (or the appropriate LED, wire, correct resistor and USB Plug
A small piece of clear plastic sheet (OHP sheet or bit of old packaging)
Some cardboard and or foamcore (not necessary but nice)
Some low value loose change
Soldering iron
Hot Melt Glue gun
Black and silver paint (spray or markers)
About 1.5 to 2 hours to spare doing this project

Step 1: Find a Couple of Suitable Bottle Caps

Actually you only really need one, for the spotlight itself, although the other cap is useful for the base, the base could easily be made out of cardboard. here you can see the top that I used for the main part and the bottle it came from.

Given the shampoo only cost about 50p for 750ml, it would be worth buying a bottle just to use the cap and then keeping the shampoo as hand wash or shampoo refill.

Note the fact that the cap is translucent, this is quite important, because in the real spotlight there is quite a bit of light leakage through the cooling vents at the side of the lamp, and the translucent cap lets us mimic this effect rather nicely.

The single serving drinks sports cap is nice because the push pull closure also rotates, which means that the finished spotlight will be able to rotate, although this is not really necessary, of course unlike the real one, your USB spotlight won't need a crane to turn it round.

Step 2: Wrap Top in Foil Strips

First prepare the cap by removing the flip up lid part. Cut it off with scissors or a craft knife and then cut off an lumps and bumps, such as hinge ends or catch notches. (discard the flip up part of the lid (or keep in making box for another project).

Put some double sided strips on the back of your thick foil, then cut into strips that are thin enough to fit about 5 strips with small gaps over the height of the cap. My cap had the product delivery hole slightly off center. I decided that I would make this the bottom of the lamp so I made certain that my strips all met at the bottom. We are going to cover the join up anyway.

Step 3: Add Reinforcing

On the real Spotlight the air vents don't go all the way round,so to give this effect, cut some wider strips and stick them across the other strips from the edge of the first strip to the end of the barrel and arrange them at 1/4 intervals round the circumference.

Step 4: Build Power Supply From a Cork

Well it's not a real power supply, it's just for show. Easiest way is to carve it out of an old wine bottle cork. The top side needs to be curved to fit the curve of the spotlight, but nearly the right curve will do. To cover up any poor joins, make the foil at the sides a little longer so it can flap up round the main barrel slightly.

Glue the foil on with hot melt, double sided, or fast setting two part resin epoxy.

Step 5: Attach Power Supply to Base of Spotlight

Stick the power supply to what is going to become the bottom of the spotlight

Step 6: Colour the End of the Lamp Barrel

Either mask off or just colour in with silver marker like I did. Don't colour the sides, leave those translucent.

Step 7: Cut USB Plug Off USB Light

Well I tried to get the wires out without braking them, but it seems impossible as part of the wire is embedded in plastic that was cast in after the thing was put together. So plan B...

Cut the lamp assembly near to the plug using strong pliers.

Step 8: Take Out the LED and Its Wire

The lens almost falls off the end of the device of its own accord. Once the other end has been cut, the LED can be coaxed out easily. For this project you now only need the LED, its wire and the USB plug, everything else goes into the making box or the bin.

Step 9: Fit LED to Spotlight

Crumple up a bit of tin foil and shape it a bit into the shape of a reflector. Make a hole in the reflector and thread the LED through it , secure with glue and take care that the LED leads don't short out against themselves or the foil reflector.

When you've done it should look a bit like this... see second picture

Step 10: Hack the USB Plug Apart

Using a sharp craft knife, carefully slit down one side of the plug rubber outer moulding. Don't worry about cutting anything inside... you won't, it's all protected by a metal case.

Once you have slit it you can peel the rubber cover off the metal parts. It might put up a little bit of resistance because it was moulded into place, but it should come off all in one piece and relatively easily. What you see immediately is a metal case.

The metal case is made up of two parts . to separate them, you first need to unwrap the top part cable grip. Once you have done this the top case part opens up on two little semi hinges and then can be lifted off.

Inside you'll find more messy rubber, you have to pick this off. It does come off quite easily, but you will quite probably break the thin wires in doing so. This doesn't matter at all because you are going to be soldering new ones on anyway.

When you have taken it all apart you can solder the wires that go tot the LED back on to the relevant pins, see diagram. The middle two pins are NOT used.

Step 11: Hack USb Plug Back Together

Putting the plug back together is the reverse of taking it apart, except that the potting agent, is the trusty hot melt glue instead of injection moulded plastic.

Put some hot melt on to the soldered pin ends and quickly press home the top little hard plastic cover. Trim off any hot melt that gunges out the sides.

Slip the white plastic rectangle back into the metal case and put the metal case top back on and close the cable grips back up. Squeeze a little hot melt glue into the metal case to pot up all the wires and provide strain relief.

Offer the metal case up to the rubber outer housing to see where it should go and then as you put it back on put a tiny bit of glue gun glue at the wire end of the plug and wrap the rubber cover back round the metal case.

Stick the slit edge of the rubber cover with Super Glue (Cyanoacrylate). Most soft plug mouldings are made out of the same plastic (PVC, vinyl or rubber) as the wires and Super Glue sticks them very well. (remember it also sticks skin better than almost anything else, so NEVER let children do this bit of the project).

Step 12: Make the Spotlight Lens

Place a sheet of clear plastic (OHP slide or old bit of packaging) over the top of the spotlight and mark a circle (water based ink) just inside the inner wall of the lamp. Add three tags to the circle and then cut it out. Then wash off the marker pen, and then dry. When dry, stick a small square of double sided masking tape to each tag, but leave the backing on for now.

Measure the inner circumference of the lamp and make a foil strip that will fit neatly inside the lamp without sticking up proud from the top.

On a similar piece of foil mark up and then cut out the Batman logo. The logo must fit the area of the lens. Put a strip of double sided sticky tape on the back of the foil before you cut it out.
Get images to copy from off the web, or go to thedadcando batman project where there is a downloadable template of the bat logo (and the mounting yoke, you will need in a minute).

Cut out the bat logo and using double sided tape stick it to the lens in the center. Fold the tags down.

Insert the foil strip into the lamp and then insert the lens tags and push the lens down so it is level with the top. The best way to down this is to peel off only one of the tags double sided, poke this tag in and stick it firmly and then push the other tags in and pull off the double sided backing with tweezers or the corner of your craft knife once the tags are in place.

Make sure that the tags go down in between the foil and the lamp wall, so they are hidden when it is assembled.

Step 13: Glue on the Yoke Mounting

Cut two small pieces of thick strong card into rectangles. colour them in black with a permanent marker and glue them to the sides of the lamp with hot melt.One on each side.

Step 14: Make the Base

To make the base I used a sport cap from a single serving juice drink bottle.

I filled the underside of the cap with 2 pence coins and hot melt and then when I reached the top of the cap I turned it over and stick it to a sheet of stiff card. When it was set after a few minutes I cut round the edge with my kitchen scissors.

While that was setting I made the support yoke.

Step 15: Make the Support Yoke

The support yoke is shaped like a big fat tuning fork. The design is roughly octagonal with the top part chopped out. Download yoke templates from dadcando's Batman project or draw up your own easily.

Measure the width of your lamp with its extra side pieces and just make sure that it is a sung fit in the yoke. I used foam core for the yoke, but you could use much nice materials. Two bits of card glued together, thin plastic or thin wood for example.

Cut the bottom prong so that it fits into the hole in the top of the drinks bottle.

spray or paint both the yoke and the base, black and then stick them together using hot melt or any other quick setting glue

Step 16: Assemble Lamp Into Yoke

Because of the drinks top it will turn, but if you want to to be adjustable for rake as well then you'll have to secure it with pins or thin nails. Form me I only wanted the turning as a gimmick, the fact it sits there next to my computer displaying the Batman logo on the wall is just too cool.

I've loved doing this project, I feel many more USB light type projects coming on, it was so easy and the effects are really cool.