Break out your Pink Floyd albums, because it is time for you to have your own personal laser show. In fact, it cannot be stressed enough just how much "awesome" you are getting out of such an easy to build device. Watching the patterns spiral out of this little box onto a large wall is much more mesmerizing than it really has any right to be. Most people of the people form whom I demonstrated this for have agreed that they could probably watch the laser patterns dance all day without getting board. I can only imagine how your cat might respond. There is only one way for you to find out! You're going to have to build one.
Step 1: Go Get Stuff
You will need:
- (x4) Paint storage cups
- (x3) 1" round mirrors
- Project Enclosure (7x5x3") (Model: 270-1807 | Catalog #: 270-1807)
- (x3) 1.5-3VDC Metal Gear Motor (Model: 273-258 | Catalog #: 273-258)
- (x3) 25-Ohm 3-Watt Rheostat (Model: 271-265 | Catalog #: 271-265)
- Pen-Style Laser Pointer (No model information available | Catalog #: 63-1064)
- DPDT Submini Toggle Switch (Model: 275-614 | Catalog #: 275-614)
- Enclosed 2 "AA" Battery Holder (Model: 270-408 | Catalog #: 270-408)
- 2 "AAA" Battery Holder (Model: 270-398 | Catalog #: 270-398)
- (x3) Hexagonal Control Knob with Aluminum Insert (Model: 274-415 | Catalog #: 274-415)
- Enercell® "AA" Alkaline Batteries (4-Pack) (Model: AA-4PK | Catalog #: 23-849)
- Enercell® "AAA" Alkaline Batteries (4-Pack) (Model: AAA 4-PK | Catalog #: 23-850)
- Assorted short zip ties
Step 2: Mark
Lay a motor flat on top of one of the paint storage cup lide. Make two marks on each side of the motor.
Repeat for the remaining two pairs of motors and cups.
Step 3: Drill
Drill through all of the marks that you have just made with a 1/8" drill bit.
Step 4: Zip Tie
Using the holes that you have just drilled, firmly zip tie the motors to the paint cup lids such that the gears stick out over the edge of the cup.
Step 5: Attach Mirrors
Hot glue the mirrors to the center of each of the motor's gear. Try to center the mirror, but don't worry about getting it completely perfect. It is these minor imperfections that will later help form the spirograph's unique display.
Step 6: Attach Wires
Solder a red wire to the terminal of the motor labeled "+" and black wire to the terminal labeled "-".
Step 7: Insert
Hot glue the motors into the center of the case such that two are side by side and one is opposite and centered between them. Basically, the laser will later need to bounce between them in a zig-zag. That said, it helps to have this entire arrangement turned at a slight angle within the case.
Step 8: Take Apart
Using two pair of pliers, gently twist and wobble the silver laser diode head (and board) free from the laser pen's black casing.
Step 9: Wires
Cut 6" of red wire. Expose 1" of this wire and wrap it around the gold ring on the laser diode assembly's body and solder the ring closed to make contact
Carefully solder a 6" black wire to the right terminal of a small surface mount component (assuming the two surface mount transistors are pointing up) on the side of the board opposite the switch to bypass having to press the switch to activate the laser.
Step 10: Pots
Solder 6" red wires the right terminal lug of the 25 ohm rheostat potentiometers.
Solder the red motor wires to the center terminals of each potentiometer, such that it is one motor to one potentiometer.
Step 11: Switch
Solder a red wire from either of the battery holders to one of the center pins on the switch. Solder the other red wire from the other battery holder to the adjacent pin.
Next, solder the three free red wires from the potentiometers to one of the outer pins adjacent to the red wire from the AA battery holder.
Finally, solder the red wire from the laser adjacent to the red wires from the potentiometers.
Step 12: Ground Wires
Solder the black wire from the laser to the black wire from the AAA battery holder.
Solder the black wires from the motors to the black wire from the AA battery holder.
Step 13: Cut
Saw away a 2" - 3" section of the case where you are expecting the red laser to pass through after it bounces off the final mirror.
Step 14: Drill
On one side of the lid, make three equally space marks at 1.25", 2.5" and 3.75".
Drill through these marks with a 3/8" drill bit.
Consider making secondary 1/8" holes for the potentiometer mounting tab roughly 3/16" to the left of each hole. These will allow the potentiometer to lay flat and keep it from spinning once mounted in the case.
Step 15: Mount
Insert your potentiometers into the case and firmly secure them in place with their mounting nut.
Step 16: Batteries
Insert batteries into the battery holder. You should now be able to turn everything on and off using the switch.
Step 17: Switch
Drill a 1/4" hole on the side of the case where you expect your potentiometers to be (ideally opposite from where you sawed away a section of the case).
Mount the power switch into this hole.
Step 18: Position and Glue
Hot glue the laser the top of the remaining paint storage cup.
Position it inside the case such that is will bounce off all three mirrors and then pass through the section of the casing that you have cut away.
Once you are happy with its position, glue the cup in place inside the casing.
Step 19: Fine Tune
Stick your hand or a piece of paper in front of the hole in the side of the case. Swivel the motors and the laser until the image appears centered.
If it is hitting the side walls of the case, you may want to consider widening the hole.
Step 20: Clean It Up
Zip ties all of the wires neatly together so that when you close the case they won't be going all over the place and can't interfere with the motors spinning or the laser beam shining.
Secure the battery holders inside of the case.
Step 21: Case Closed
Put the lid onto the case and secure it in place with the mounting screws.
Step 22: Finishing Touch
Affix your pointer knobs to the potentiometers.