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ArcticMyst Security by Avery

Halo Style 2 stage COILGUN

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4HV is a very strange site. Thought its cool there, but its kinda boring...never heard of a bigger forum to discuss coil- and railguns...very dissapointing.

400W....you could use a DC/AC converter...12V to 230VAC and rectify the output. Will give you 330V or something.
I prefer my chargers. Only 30x40mm (board without coil)...50W max.
Could get you ones for 100 or 200W easily. Slightly bigger ;-)
 





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^or many ZVS drivers in parallel for 400W output?

:thinking: damn.. we need electronics PROs here :(
 
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Wouldnt consider myself as pro, but a ZVS can handle lot of power at great eff.!
You could use one smaller ZVS for each stage....or charge all of them with one big ZVS.
 
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Oct 23, 2009
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so far, I've experienced nothing but FAIL just trying to build Uzzor's simple boost converter _-= Uzzors2k =-_ Project Site

The thought of trying to build a ZVS driver probably won't work if I can't even make a much more simple boost converter work properly. lol (At least for me) Consequentially the work on my own coilgun is at a standstill. I think I've got the LM311 wired up wrong. I've been having to look up data sheets and try to guess at which inputs are for which, and which outputs go over to the 555 timer. =/ Lacking a solid electrical component knowledge is certainly a downside.


Given the added complexity of the more efficient charger circuit I suspect I need to master the simple boost converter first.

_-= Uzzors2k =-_ Project Site


For the record, this is the LM311 I am using. Anyone know much about this sort of IC?
https://gb.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=2150df1569
 
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A ZVS is way easier to make than a boost-converter. I failed as well...several times...before it worked. I never know if a booster is working, before I test it ;-) so dont be hard with yourself.
These days I prever asking a friend for printed circuit boards...aint have the time to make that many boosters. Outsourcing ^^ you know.

A ZVS consists of 2 MOSFETs, 2 Zener diodes, 4 Rs, a ferrit-core with a few windings on it, plus a WIMA capacitor...
Then a transformer...trial and error...winding, measuring, tuning....
 
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The easier way to make a boost converter is a self ressonating transistor on a flyback.. hahah... 40W on a single transistor + 2 resistors. ;P

My project is standstill too, because of the electronics parts.
 
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Rush? My project has stopped nearly a month ago!
I just need to parallel the SCRS, build the charger and host and I'm done.
 
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Ahoihoi
Wow...so many replies.

Leo: Your charger? Will take some time to make some of them. Tell me asap if you need anything.

Prototype: I would aim for 250-350V for the beginning...but I would make it at least 2 stage. Ask milli...its worth the effort ^^

Coilguns havent to be portable...a nice desk-top coilgun can be cool as well.

Well, I've been reading Barry's site and have become reasonably confused as hell in regards to most things. I do know that coil length should be ~33% longer than your projectile, and you can use metal washes at the end of your coil to reduce the number of coils needed. I'd like to make a two stage one, ideally my big one will be several stages total, with a large amount of power behind it, but for now I'll stick to one or two stages with some photoflash caps. I can go bigger if it would be advisable to, my main caps are going to be 350V @ 2200μF. Though I've found some 450V 2400μF as well, but they're several dollars more each.
 
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You need a coil which is as long as your projectile.
The pulse has to end when the slug is right in the middle of the coil. So you have to calculate...measure speed after each stage, or you install detectors.

Would kinda make sense to wind a longer coil, so the way to the middle is longer...acceleration happens mostly at coil-entrance.
Not sure, but I think the field-density of shorter coils at their entrance-point is higher than the fields of longer coils.

Correct me if I am wrong, but Barry tried Iron to quench the fields and increase eff. Didnt work....I believe.
I used steelsheets to cover my coils...but it was also for stabilisation of the coil...to avoid moving.
 
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Barry did a lot of things, most of which gave me a headache trying to comprehend on three hours of sleep. But I do know he said something about the iron helping with fringe effects or something like that. I found a link to a circuit that uses four light gates for multistage triggering, they said it was good for a five stage coil gun, but I think I'll stick to a one stage or so for now. Is there a definitive source for info on building a two stage coilgun, just like step by step? I have seen a few for some single stage designs that were nice, but I've not been able to ascertain wholly the steps involved in making a dual stage or larger coil gun.
 
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It quenches the field...so the projectile has to be lurking into the coil already then the pulse hits it. Thats why I prefer contacts over IR gates. Waste of money, space and parts! Contacs switch with almost no delay. IR gates are kinda slow...trust me...makes no sense.

I will make a how to video within this month hopefully...working on a 3 stage coilgun...compact...as simple as possible. "Simple" ;-)

Regarding Barrys site: I was wondering...I tried 0.5mm wire. 10mm core 14mm coil...means 4 layers...but the sim says: 2 layers.
Why? Did he mess up switching from AWG from mm? Or is it a software-fail?
 
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None of the sims seemed to help me build my bullpup, which looks like a variation of an Uzi or grease gun. It has the barrel moved inside of the board enclosures for a snug fit. It looks better that way. I was testing it and tearing an aluminum can to shreds and then it stopped charging. So I replaced the camera charge board and still nothing. I'll do a complete rebuild after trying the coil at low power, just to eliminate which "block" in the troubleshooting method comes up "bad". I used to troubleshoot equipment at Intel, and always enjoyed doing the divide and conquer method. ;-)
 
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@Prototype
I think he was the first one to study coilguns, the site is confusing..
as a start point try the simulators I send. Don't use external irons and such things.
Just watch the electronics basics.. nothing of 28AWG with 1200A peak (simulated)...
 




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