This instructable will show you how to make a simple control box for igniting backyard fireworks displays. I made this one with the capacity for 100 independent ignitions. You may not need that many and can simply scale this down (or up) as needed (although you may need more power if you want more).
I did not get full pictures of the process, but this is relatively simple and the pictures I have should be enough.
Also I didn't have all the parts when I made this. As a result there are only 50 working controls with room for 50 more.
Be sure to follow safety precautions and use this properly. I am not responsible for injury caused by the use or misuse of this device.
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Step 1: The Parts
The Parts you will need
-A box/enclosure to meet your needs (I used a cheap Honeywell security box from walmart)
-a peice of sheet metal (12x24 - 26guage)
-A powers supply ( an old laptop supply works great - mine was 3.9 amps and 20 volts)
-Cat5 connectors and jacks (8 conductor - 1 per 4 controls)
-cat5 faceplates (with nuts to fit the screws)
-spool of cat5 cable
-a master switch (I grabbed one with an LED for arming and disarming)
-several smaller momentary push switches (http://www.amazon.com/gp/product/B0002ZPB34/ref=oss_product)
Many of these parts can be substituted based on application and I will explain that more in the specific steps.
Drill with bits to fit the switches
Tin snips (or something better for cutting the metal)
Cat5 terminator and punch tool
File (for sharp edges)
Step 2: Forming the Control Panel
Cut the sheet metal to fit the box. This will be for the control panel
If you would like an angle then leave a little extra on the end so it fits when you bend it.
You will want a snug fit so it feels secure.
Use the extra metal to form little stands for the control panel (see pictures).
Next you will want to mark where you want your buttons. ( put mine in long even rows to simplify the wiring process)
Use the drill to drill holes for the buttons and one for the master switch.
Grind down the excess metal and sharp edges around the holes and sides of the sheet metal.
If you wish, spray paint the control panel metal the same color as the box for conformity.
Step 3: Place the Buttons
I don't have pictures for this part, but you just place the buttons in the holes that you drilled for them.
it helps if the pins are all facing the same way.
Step 4: Wiring the Buttons
Cut off the end of the power supply.
Connect the ends to the master switch (positive and negative respectively).
strip a long strand of wire and run it weaving in and out the pins on the push buttons.
In the end it should connect to the switched part of the master. (this should be part of the positive side of the circuit).
I chose to cover the bare wire with electrical tape (just in case).
Optional: you may want to add resistors between the power line and the push switches. This will allow you to add more power which will make the pyro ignite faster. It will also make it more efficient if you wish to ignite more than one at a time.
Step 5: Putting in the Plates
You will need to cut the back of the box for the plates. Make sure not to cut too much or the screws won't attach.
Once you have cut the holes, mark and drill holes for the screws to attach to.
Attach the plates with the screws.
Step 6: Connecting the Cat5
next, connect the other side of the switches to the Cat 5 connectors.
I accomplished this using short segments of Cat 5 cable.
On the Cat 5 connectors, terminate the cables on the solid colored terminals only following some type of order that you will need to continue using throughout.
The last picture shows how I arranged the connectors
Depending on the terminals, you may be able to snap them into place now. (check the next step to be sure.)
The negative side will fill in the striped terminals.
Step 7: Wiring the Negative Circuit
Cut a long single strand of Cat 5 wire.
Run that wire along the Cat 5 connectors terminating it in the striped terminals(white-blue etc)
attach that wire to the negative side of the master switch.
Step 8: Placing the Control Panel
Use the excess pieces of the sheet metal as stands for the control panel.
Strong magnets are a good way to hold everything in place while allowing for easy access.
Seat the control panel on top of the metal strips.
Step 9: Ignition Wires
For this part, terminate the cat 5 cable with standard cat 5 connectors on one end and gator clamps on the other. (cut to the distance you want to be away from the pyro. I recommend at least 50ft for consumer grade shells.
be sure that the solid cable lines up with one of their positive pins (taking note of which one it is and writing that down) and line up the striped cables with any of the negatives.
be sure to follow some sort of order so you don't get confused later.
I followed the same order as before to limit confusion
Be sure to test everything with a volt meter before using it.
Step 10: Setting Up the Display
Step1: place pyro where it will be ignited from.
Step2: wrap the fuses in a short segment of Ni-chrome wire leaving either end poking out from the fuse.
Step3: Set box where it will be operated from.
Step4: run the cabling from the box to the display
Step5: attach the gator clamps (1-positive and 1-negative) to either end of the Ni-chrome wire (taking notes on where it is connected will be helpful)
Step6: attach the cable to the box
Step7: plug in the box and switch on the master switch
Step8: Hold down the button for a few seconds. The wire will glow orange and then ignite the fuse (Caution the wire will be hot)
Step9: Be safe and enjoy