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Disposable Camera Hack? Answered

Hi, im building a capacitor bank for my coilgun, and I have 17 disposable camera capacitors in them.
(wired in parallel (or whatever one means + is atached to +, and - is atached to -))
But for some reason wenever I start chrging it, after a little wile, it makes a huge spark across one 
of the capacitors. That probobly means its arcing right? but its only 300 volts
(there wired in parelell so only the amperage goes up, not the volts). 

I then tryed to charge the caps to a point before they arced, wich took about 1 min (the battery is full)
and my ammo only shot 3 inches! 17 capacitors, charging for 1 min, and it slid across the floor 3
inches! I have no idea what im doing wrong. Im using wire from a microwave motor 
(wich is realy small) for the coil, and its 5 layers thick, wrapped around a hollowed out pen.


So, to sum it all up, here are the main problems:
1) the caps arc when charging
2) the ammo only goes 3 @#%!ing INCHES!!!!!! arg!


Ps, i heard someware, that if you have enought amps, it will arc even with lower voltages.
Maby thats whats happening?

Discussions

1) It sounds to me (and the first picture seems to confirm it) like your wires are too close together and arcing is occurring at a fairly low voltage...
2) which means your capacitor bank will never fully charge.
.
.  It volts that make an arc. Got to have amps to maintain it, but volts determine how far it will jump.

 but 300 volts isnt enough to make it arc, the closest point at any two wires is about 3 mm

.  Well, if you have arcing, you have some wiring too close together, some carbon tracking, or some other "short."
.  Or possibly a bad cap. Try removing the cap that arcs from the bank.

 ok i tryed that and it works! thanks! i got rid of the bad cap. but theres still the problem of the gun only shooting 3 inches...

.  Are you sure you're getting 300V? Have you measured it with a voltmeter?
.  How far do similar designs shoot? Do you have enough capacitance (looks a little small to me, but I'm no expert)?

 Somewone from another forum said I should use a thicker wire, with less turns, because the electricity was being distcharged from the caps too quickly.

.  Certainly worth a try. But it seems to me that thicker wire with fewer turns would have less resistance and discharge the caps even faster. (Which should give you more oomph)

 ok i tryed with some thicker wire, but i think it was to thick. how thick should it be?

.  I don't know. You need to find some plans that show the proper dimensions or do some experimenting (or both).

 well theres tons of plans online, but i have no idea wich one to use...

.  Then maybe you should try something different until you get a little more experience.

 im very experienced with high voltage. how am i suposed to get more expirence with coilguns without making one? im just wondering if u know any good guides

.  I have a hard time believing a 13 yo is "very experienced with" much of anything.
.  Learn to crawl before trying to walk.
.  Don't know of any.

 "We have a "be nice" comment policy. Please be positive and constructive with your comments or risk being banned from our site."


JEEZ! way to rain on my parade!

.  If you think that busts the "Be Nice" policy, you obviously haven't seen many of my other posts.
.  Well, I can either "rain on your parade" (actually I'm just suggesting that you wait until you learn a bit more, not call the whole thing off) or sit back and watch you zap yourself.

> so i do consider myself "very experienced with" alot of stuff,...
.  I didn't see a lot of high voltage on that list.

> thank you very much!
.  You are welcome very much

> you old guys (no offence) ...
.  None taken, you young turd. :)

> think ur so smart
.  Not so much smart as "been there, done that, got the scars to prove it, trying to help you avoid the same."

> have u noticed i use brackets alot?
.  No, but you use parentheses almost as much as I do.

> ... the rail gun failed horribley.
.  Surprise!

 also im building that combat robot, and i built a lifter and entered it in my school science fair. (the lifter was a bit overkill for the fair tho).
i also have a horde of collected electronic stuff from scince i was like 2. (im being sarcastrc)

so i do consider myself "very experienced with" alot of stuff, thank you very much!

you old guys (no offence) think ur so smart

have u noticed i use brackets alot?

 ive built a tesla coil, and built a rail gun.but the rail gun failed horribley.

 TOO EVERYONE. sorry for my bad speling im typing on my ipod and its hard to hit all the letters

 I found out why its arcing. there was a tny little peice of solder stickng out. t was almost imposible to see. but it was realy close to the other side of the caps. I can now fully charge the caps.


there are about one or two tiny clicking sounds every time  charege it tho. is that bad?

What are you charging it with exactly?

L

 the charger from the disposable cameras

The 300V line or the higher trigger? I'm unable to explain arcing under those circumstances with what you say and show.

L