How is this hobby cannon made?

[Lunes]

Hello, i try to make a cannon like this one

but i can’t find any information on how the ”green kinderegg” that holds the components and battery is made.

Any ideas on how this is made?

 

[dave9]

The green kinderegg is nothing more than a housing to mount the 9V battery connector (cut a hole and use epoxy or hot glue), the terminal block that attaches the wires (again epoxy or hot glue), with a switch in series between the 9V positive lead and one of the terminal outputs.

Right after the switch, between it and the terminal block you'd place an LED (cut a hole and use nothing, just friction to mount it in thin plastic if the hole is the right size), it's anode to the positive after the switch, and its cathode to a resistor in series which then is wired to the negative battery terminal connector. The resistor could be around 680 ohms, 1/8W or higher, for a safe median level of current (around 10mA) through the LED.

Personally, I would use something a little less flammable than cardboard tubing to build the cannon barrel.

 

[Lunes]

The green kinderegg is nothing more than a housing to mount the 9V battery connector (cut a hole and use epoxy or hot glue), the terminal block that attaches the wires (again epoxy or hot glue), with a switch in series between the 9V positive lead and one of the terminal outputs.

Right after the switch, between it and the terminal block you'd place an LED (cut a hole and use nothing, just friction to mount it in thin plastic if the hole is the right size), it's anode to the positive after the switch, and its cathode to a resistor in series which then is wired to the negative battery terminal connector. The resistor could be around 680 ohms, 1/8W or higher, for a safe median level of current (around 10mA) through the LED.

Personally, I would use something a little less flammable than cardboard tubing to build the cannon barrel.

If i want to upgrade this cannon with two barrels instead of one, what’s the easiest way to do that? If i attach the wires from both barrels (total 4 wires) to the same terminal block (or to two different terminal blocks attached to the same battery) the barrels will shoot simultaneously.

Is it possible to make them fire in succession manually? or does that requies two batteries and a switch button for each barrel?

 

[Audioguru]

What is the white-hot wire from?
What explosive material? Gunpowder?

 

[dave9]

If i want to upgrade this cannon with two barrels instead of one, what’s the easiest way to do that? If i attach the wires from both barrels (total 4 wires) to the same terminal block (or to two different terminal blocks attached to the same battery) the barrels will shoot simultaneously.

Is it possible to make them fire in succession manually? or does that requies two batteries and a switch button for each barrel?

If you want them to shoot simultaneously you will need to make sure both lengths of ignition wire are very near the same length or else one will take more than its share of current. You might also need two parallel connected 9V batteries to supply enough current, or a higher voltage source with more current would probably work too (guessing, I've never made this cannon from what looks like notebook binder wire?).

If you want them in succession you just need two separate switches or a dual throw switch to fire each in turn and won't need a 2nd battery or higher voltage. Anything fancier than that seems a bit excessive for what this cannon is. Many things on youtube are interesting in that they can be done at all but dwell more on using very common materials rather than the best materials fit for purpose. For example why use match heads when gunpowder exists, at least in the US we're gun-crazy and can get gunpowder at any local gun shop. Then again, gunpowder would make this that much more dangerous.

 

[Lunes]

If you want them to shoot simultaneously you will need to make sure both lengths of ignition wire are very near the same length or else one will take more than its share of current. You might also need two parallel connected 9V batteries to supply enough current, or a higher voltage source with more current would probably work too (guessing, I've never made this cannon from what looks like notebook binder wire?).

If you want them in succession you just need two separate switches or a dual throw switch to fire each in turn and won't need a 2nd battery or higher voltage. Anything fancier than that seems a bit excessive for what this cannon is. Many things on youtube are interesting in that they can be done at all but dwell more on using very common materials rather than the best materials fit for purpose. For example why use match heads when gunpowder exists, at least in the US we're gun-crazy and can get gunpowder at any local gun shop. Then again, gunpowder would make this that much more dangerous.

I made a sketch of it to understand this better

So a SPST/single barrel works like this? https://imgur.com/xONsLEI
And the easiest way to make a double barrel cannon that shoot in succession, with the power of one battery, is this? https://imgur.com/EbvYDXv

 

[dave9]

The second pic for succession won't do anything, would need to be more like the following:

Previously when I wrote "If you want them to shoot simultaneously you will need to make sure both lengths of ignition wire are very near the same length or else one will take more than its share of current." I meant the metal heating element wire. The insulated wires leading to those do not need to be the same length, practically speaking... extreme differences in the lengths of those, if one were very long could add significant resistance but not the lengths I imagine you'd use and it won't matter if they're not fired simultaneously.