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FrozenGate by Avery

BIG capacitor bank

IT would, and work well, but these were just a tad more expensive than the pipe, and so I chose the less strenuous option (i.e. not banging flat some pipes) to make my bars.

(we get raped on prices in hardware stores over here)
 





Not here mate - big country, unlike the states, large distances between towns, so big bill.

I just finished a little circuit that will be useful on the streets. It's designed to run the horn (the vibratone) when you get in my way. I am sick of pushbikes on the footpath (which is breaking the law, coz thats illegal here - wheel = road!), and prams. Singles I'll ignore (one child) but the big 2 or 3 kid carriers, "BARRRP BAAARRRP". :)

Seriously, this post is getting right off topic, its meant to be about my big cap bank; but F### it S#### me when people have no manners (and I am not in NO way referring to anyone on this thread or this forum in general!).

Now back on topic. A mate of mine who works for a big company had me fix his iphone. Fix yeah right, eject the sim after spending $1.50 on paper clips, and reinsert, find its dirty, clean it (Water helps here, plus a blow job from the pubs hand dryer in the dunny); and it said "Hello! Telstra here!". For my efforts I got (and you guys know I already have a smaller one) a REALLY BIG Pudk SCR and a lot of other components. They're new, never used. So, I'll keep the little puck for smaller (ish) experiments, and the big bugga can go onto my "Thumper" :)

(yes I am happy, this "repair" didnt even need the kiss of the soldering iron!)

edit: damn it - big bugga wont fit into the clamp, so I guess I am using (and abusing) the smaller one :P
 
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Going up to the hardware store tomorrow, to grab some 10-32 or M6 bolts (whatever my caps take; thanks for the tip GBD!) after perusing the data sheets. I'll also buy a suitable drill bit and star washers, along with a centre punch, hacksaw and a G clamp. I can then clamp the bus bar to my workbench (with a suitable diposable block of wood) for drilling and cutting purposes. Then I will be able to assemble my bank in the 450V configuration and start working on the control console. Switches will be changed for smaller ones driving relays, so I dont need to buy a second box.

I charged one cap up today to 400v, and discharged it with a piece of wire on an 8 foot piece of poly pipe (so I could keep well back). The noise was deafening and the flash was like one of those big studio umbrella strobes. My ears were ringing for ages afterward. I'm going to check out ear defender prices while I'm up at the hardware shop! Probably should get some saftey glasses as well. This project is going to be DANGEROUS when its finished!
 
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I would suggest getting a full face shield along with those goggles, last night with my smaller bank sent some shrapnel my way (loosly connected stranded cable went boom as I was shorting the bank).

30bd reduction or so (earmuffs) seem to work quite well for <5KJ banks, at 8ft away though with your stick, you should be alright.
 
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hehehe I want to be 30 ft away with the control console, not in blast range of the caps! Still one can be never careful enough and approaching an unexploded targer with face sheild, earmuffs and gloves would be a wise idea (and a long insulated stick :) )
 
Are you going to have some sort of redundant indication system that the caps are charged? LEDs with some huge resistors or something? Just in case your power or something dies and you can't read the voltmeter anymore.
 
1000V analogue voltmeter right on the bank box - it needs no power to work (except charge in the capacitors) :)

Also the bleeder resistor fails "safe" - that is, should the 12V DC fail, the resistor drops inline and starts draining the bank.
 
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Yeah, I did a similar thing for my tesla coil. After shorting the caps out by hand once, wasn't gonna do that again!

So I set up 2 10W resistors in series thru a relay, so when the main power was turned off, the relay would drop the resistors across the capacitors, draining them in about 30 seconds. A lot less wasteful than permanent bleed resistors, but also a bit less redundant. Not a problem if you're always careful and check anyway.
 
Yep - the meter is about 3 inches square, so easily seen from a distance. You'll be able to sit and watch that wasted bang waste away through the resistor :P
 
The more and more you talk about it the more and more I think about thumper :D

Can't wait to see it finished!
 
LaZeRz said:
The more and more you talk about it the more and more I think about thumper :D

Can't wait to see it finished!
Click to expand...

You are in sydney. Once it is finished we can take it some were and you can see it going. In person. BYO eardefenders and face shield. Its even gonna be called "Portable Thumper" due to its portable nature running from a SLA battery.

Flaminpyro said:
So you want to do something really cool with them capacitors, try coin shrinking, this guy has been doing this for years :cool:

Bert's Quarter Shrinking and Can Crushing Gallery
Click to expand...

Or bending hard disc platters as they launch skywards. I have plenty of old hard discs to take apart.

So far the specs and tech details are:
* Electronic inverter charging system based on a Royer oscillator and a LM339 comparator for cutoff voltage sensing. I didn't design this, but I did design the PCB (and got 10, so I can afford a few mistakes).
* Dual voltage selection - 425V and 850V
* Remote switching console. Will have its own 11.1V LiPo, to provide power to the voltmeter it contains, and the 12V nominal to the relays and contactors, along with the press buttons
* 12V power source right in the bank box. This powers the inverter, the scr firing mechanism and the alarm/strobe
* Non mechanical SCR trigger capable of wistanding pulses of around 17,00A at 1200 volts
* True voltage readout at the remote console. Voltage is monitored at the bank and set back to the console as a 0-100v signal, which is calibrated at the box for voltage loss over the return line to the remote console
* Vibratone 450 (classic american school fire alarm) warning horn, red flashing strobe for bystander awareness
* Multiple failsafe systems, including a big bleeder resistor that drops into line as soon as a fault is detected. All analogue so no digital stuff to make mistakes. Meter on bank box with BIG scale that can be read from a distance should the remote fail
* Finally, a spectator handpiece for when I want to allow a spectator to "push the button"

Power output will be ~2.5kJ to begin with (2430 by specs), but will be doubled when I can waste ahem blow errr consider purchasing 10 more caps. These I will be able to drop right in, and bolt up. Just move charging board, slide them under the rails, and bolt them in, instantly doubling the capacity to a hair short of 5kJ (4860)

I just need a few minor parts to complete it (which I am buying next week) and then I'll get to finishing it. Bus bars are marked for centre punch, but I forgot to get a G-Clamp to hold them during the drilling process.

This project I want to finish before 31st december, as then I can fire it off midnight new years eve :D
 
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Flaminpyro said:
So you want to do something really cool with them capacitors, try coin shrinking, this guy has been doing this for years :cool:

Bert's Quarter Shrinking and Can Crushing Gallery
Click to expand...

You will have a hard time shrinking coins with Vk's capacitor bank.
To shrink coins, or crush cans even, this requires a high rise time, something that electrolytics can't deliver due to thier relatively high ESR. This is a job for pulse capacitors.

I would however, like to see maybe an application for a coil gun or an ETG.
 
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GBD said:
You will have a hard time shrinking coins with Vk's capacitor bank.
To shrink coins, or crush cans even, this requires a high rise time, something that electrolytics can't deliver due to thier relatively high ESR. This is a job for pulse capacitors.

I would however, like to see maybe an application for a coil gun or an ETG.
Click to expand...

Yes, look at the bank TGG is using to shrink quarters - its some massive pulse caps they have there. I just compiled a list of parts for the trigger board. Since its all low voltage, it can be constructed on strip board, and is going to cost me (wait for it) $11 from jaycar. :)

and anyway PFFT - your building one too GBD - mines a disc launcher / wire exploder - you can build the coil guns / ETG's :)
 
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Just a suggestion, either way the latter will wreak some havoc :eg:
 
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