Disposable camera coilgun

Step 3 Preparing for the real stuff

- Connect the capacitors in parallel, that is, connect the (+) and (-) sides to the (+) and (-) sides of the other caps. This is performed easily by using a universal circuitboard.

- Connect the string of caps to the connections on your flash-charger circuit board you marked earlier.

Comments

[electronicfreak22]

When you say attach them in parallel,(I'm not very good with electronics)does that mean attach the (-) sign to the (-) sign on the other capacitor? Thanks

[sverige]

If you need high current, you would wire them in parallel, positive to positive.
If you need high voltage, you will need to wire them in series, positve to negative

[AlfonsVH]

That's correct!

[cherwa]

do you have to put the capacitors in order from biggest to smallest? or can they be the same size?

[penguin27388]

no, it dosn't matter in parralell the capaciter volts/uf are added together

[vbexpressrocker]

No, in parallel the capacitance of the capacitors are added, not the voltage.
In series, the capacitors voltages are added together, and the capacitance is taken away from each other.

[leven]

If you need to ask that, you should not try this.. the 300 volts cap would have no trouble killing you.. so read up a bit on basic electronics and you will now the answer, and how not to kill yourself.

[LeelaKrishna]

I tazed my self atleast 300 times with just one capacitor of 330v and hey i'm still here It just hurts like hell for about 2 mins

[badideasrus]

i care to disagree. 300 volts means crap if the amperage is super low.... like a flash camera's cap is. besides, volts don't kill, amps do.

[usb key]

A diagram would have been nice

[Ma77h3w]

I created one using just the circuit from 1 disposable camera.. and used a push switch to activate it. This welded shut and was rated at 250V ac at 5A I've got a relay to do it now rated at 28V dc / 277V ac at 12A. Will this work? What sort of current goes through a coil like that? My coil has almost no resistance

[padmanabhapsimha]

you do not need 28 v dc to activate the relay. usually relays need 9 to 12 volts to activate them. your relay's ratings is the maximum voltage and current it can switch.

[zack247]

you will need close to 28v to activate it, try finding a car relay at your auto wreckers, they can be activated by 9v and are simple to use.
one is used in this instructable: http://www.instructables.com/id/Coilgun-Handgun/

loko at picture 2 of step 4 to see how it is wired up. on the bottom of some relays there are markings, the two pins marked with a swirly sort of line is where you put the 9v, and NO and COM are your "switch" leads

[zack247]

COM can also be labeled as just C, too.

[Ma77h3w]

Ah I know how to use a relay. and it's a 9 v activating voltage, those were just the ratings I mentioned before. I'm just wondering whether it would fuse. Cause I'm sure more than 12 A goes through it when it's connected to a coil like this

[zack247]

relays dont generally fuse, it should be alright.
im not sure if relays have the max current that you can put through them labeled on them, some do, if you want to be extra sure then check your relay and see if it says anytihng.

[Ma77h3w]

Yeh it says 28V dc / 277V ac at 12A
Hard to know the current through such a short coil like that. I imagine it'll cope with more than 277V ac at 12A if it's just a pulse. The ratings on it are for a continuous ac or dc voltage, so I guess I'll find out when I finally try!

[sunal135]

i have similar problems; if some one who knows about relays could help.

[Ma77h3w]

Also I have loads of 0.1uF Capacitors:-
Class X2 Metalised Polypropylene Capacitors
Voltage rating - 275Vac
Tolerance +/- 10%
All carry international electrical safety approvals.
Typically used as suppression components.

Would these be suitable for a coil gun? They're some of the few high voltage capacitors I have. I imagine I wouldn't want to increase the voltage above that of the standard camera flash charge circuit, but would I instead use a thicker coil wire for more current?

[frixx]

you have to connect the caps in serial to increase the voltage

[Vator]

And in parallel to increase the µF?

[DavidRobertson]

 You mean capacitance.

[badideasrus]

.... isn't that what he said? (seriously, i don't know the diference between capacitance and farads)

[DavidRobertson]

No, (micro)farads are the units. That's like if you were to cut a strip off of the end of a piece of paper and saying that you have "decreased its centimetres", when the correct statement would be that you have "decreased its length".

[badideasrus]

would saying 'the amount of uf' be proper? and thanks for exsplaingin that...

[erty311]

Will a 1000 µF 35v capacitor work for this project? or do I need a higher voltage capacitor?

[max1zzz]

 what would happen if i used 2200uf pc motherboard caps

[leven]

They would go POFF, and the blue smoke would have been released.
they are rated someting like 6 volts, while the flash charges up to 300 or something like that. 

[mjohnson22lr]

How do you attach the capacitors to the breadboard?

[flash circuit 2]

Do you attach the flash circuits to the circuit board out of the camera? If so, I have a kodak board and I don't know where I need to solder them to. thanks

[AlfonsVH]

Check out this file: http://avhproductions.be/files/dccg-ad.pdf

[mjohnson22lr]

This link is broken, can anybody help?

[rippinblaise]

I put everything together and i got the capacitor bank to charge and i got a huge spark when i discharged it with a screw driver. But when i hook it up to the coil, the nail/screw/ammo doesn't move at all.... How did you get this to work Email me about it at [e-mail]

[SciriusDoomus]

It's best if you put the ammo in the back half or behind the coil. This is because the coil needs to become magnetic and draw the ammo forward to make it go fast.

[Orchestrapit]

make sure there are not too much or not enough turns in the coil. also, try playing with different projectiles and placing them in different positions around the coil. i get good results if i put it (a small screw) in the back half of the coil. make sure you do not put your projectile in the middle of the coil, because that will just hold it there and not do anything cool.

[aplauche]

could you give me some specs for the average capacitor found in a camera? i have a bunch of good condition capacitors lying around from other projects, but i would like to know the power that you generally use. also wouldnt using one huge capacitor rather than four medium ones decrease the charge time?

[bylerfamily]

The average camera capacitor is 330v and 80 to 160 uf.

[Baddul3]

How do u attach all of the capacitors to the leads of the original capacitor?

[upinthecloude]

ummm... im having a bit of trouble here... if I'm using a universal circuit board... do it matter where i solder the capacitators or are there particular coordinates... i know im not very good at this stuff either...

[flash circuit 2]

o yeah im askin if this would work taking the long metal peice and solder the capacitors to that the a wire the solder the wire to the lead of the other capacitor