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Electric Lift Igniters


Sparx88

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Been testing some ideas and have come to these for direct lift ignition. A control board is in the works. These can be used in any way that ematches are used, I made them for lift purposes for now. They are of 24 gauge solid core ( 4x24 utp Cat3 phone cable) using a stainless steel bridge and aluminum infused BP slurry. 30 awg nichrome wire to be used. They fire instantly with 12volt at 2 amps on a 50 ft length of the same phone cable. I can have up to 4 shells wired on each cable and have a dozen of those running to the box. The batteries are D cell Lipo's 3 volt 2000 mah, 4 per pack. I have 5 of those packs so I'm good on power for a couple seasons. Just thought someone could benefit from this or inspire some creativity. :)

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The video is of the first shell sent up by one. It was heavy fog but had a cool effect. It was an attempt at TT to Turquoise. A little fast imo. Need a longer TT duration for sure and lower the magnalium content on the turq. Bright as all heck though lol.

 

 

 

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I've always been a bit worried wiring up a shell (or any firework for that matter) prior to transportation, just from the odd chance it gets energized and sets off.

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Is this something that happens? I mean I thought about it and it would severly suck for that to happen. I chose the stainless to start, to raise the power required to melt the bridge. The stainless coils are in no way easy or cooperative to work with and was chosen only for corrosion resistance and relatively higher current handling than most nichrome I have used.

 

I'm worried more now. I'm glad you responded truthfully. Though I have to say for now, I wire these the same day and am loading and firing one at a time. The video was just that, the first shell using one of these and was the only shell at that time. I will admit I do have 3 wired in storage. Which is a cardboard box in a non-functional floor freezer. I know, not optimal, it's what I have.

 

Are shells or pyro lifted like this commonly? I know some are when it comes to precision timed displays. Which is why I'm exploring this, to go along with music and sound effects that are difficult to do do well. I'm a metal head since the day it was born and love the combination of heavy music with pyro. Music from Bands like Crimson Moonlight, Living Sacrifice, Extol, Saint, Stryper, Apostle, Bride, PFR, Newsboys, Vengeance (Rising), Royal Anguish, Morification, Golden Resurection, 90 pound Wuss, Rez, The Crucified, Believer, Messiah Prophet, Thousand Foot Crutch, Antestor and the list goes on and on etc etc etc etc. So to have this all work well would be right awsome.

 

Any ideas to make this safer? Maybe using 16-20 gauge nichrome instead of 30 gauge? It's working so well now I want to be able to continue doing it. Like a cure for ED :P. Seriously though, whats the haps?

Edited by Sparx88
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You will want to store the wires shunted (twisted together). The main concern with storing or transporting previously matched product generally is a result of the sensitivity of commercial e-matches. This is a bigger problem when the match is placed directly into the lift cup with the abrasive lift granules.

 

I'd still be uneasy, even though it sounds like ones you're making should be much less sensitive. Maybe consider inserting a port to the lift charge, so the match can be added on site, but still have the accuracy of directly matching the lift.

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If you got quick or tape match just use about 10 cm, this way you will till be precise and it i easy to fit the e-match on site.

If youwant to add it directly to the lift cup, poke a hole big enough for the e-match into the lift cup (prior to loading) and close up with some asking tape.

When loading a shell just pull of the masking tape, insert e-match and fix the ematch with some tape, takes about 10 seconds for a shell if you prepare yourself. But be cautinous not to rip the match out of the cup during placing in mortar, often it is not suited to be used as a lowering cord (if you want to use it as lowering cord use at least two strip of masking tape, one at the hole, one at the top half of the shell, and only up to 4").

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Yep, thats seems to be the ticket. I already use cotton string loops on the tops of the shells for lowering. Poke hole, insert and hot glue from the inside before placing stars. You can see it partially in the pic. And I was hot glueing the igniters in place where they come out the lift cup to seal that off. However, waiting until I'm going to load the shell to insert igniter and fixate with some tape will have to be they way like you guys said. I will most likely use SAT (Sticky Ass Tape brand) to do the taping. Really sticks and conforms to contours well.

 

I'm getting excited again :)

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Just sharing my experience.

 

I work with a display company and we prewire every single shot of the show (600-800 shells) on a trailer prior transport. We have never had anything go on the trip

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Correct me if I am wrong, but I think 2 professional pyros died when there entire van blew up which contained pre-wired ignitors?

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Just sharing my experience.

 

I work with a display company and we prewire every single shot of the show (600-800 shells) on a trailer prior transport. We have never had anything go on the trip

But do you match 'em straight the lift or at the quickmatch? At the quickmatch it should be quite safe, since it is hanging free , in a way that it can't get hit.

But this isn't the situation in day box. Also if we talk about us shooting shells, we are nearly always talking of a max of 100 shells (and thats allready a lot). With this amount there is just no real bennefit by prematching.

 

@Sparx from my experience is is enought to just hot glue the lowering cord on after pasting (for a cleaner look wrap 'em up like a spanish shell or attach the loop before the last pasting and cover the glue with last pasting). Commercial shells often use just a circle of gummed tape with a hole in the middle. Glue on the string and cover with tbe circle. Up to 6" you won't need to run tne string around the shell (just maybe on heavy multi break cannisters).

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I will only ematch a shell when its sitting in the tube- Call me crazy.


To the topic, I have seen DIY Ematch made with R-Candy stuck to the end of some exposed pyro-wire, I never tested them myself but the creator told me he has had good luck with em.

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Correct me if I am wrong, but I think 2 professional pyros died when there entire van blew up which contained pre-wired ignitors?

 

If you're talking about the North Carolina accident - nope. They were matching shells in the van, on site.

 

KO

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If you're talking about the North Carolina accident - nope. They were matching shells in the van, on site.

 

KO

I don't remember the details, it may have been this one, but I thought they tragically died on-route to shooting site, and I think authorities put a warning out about pre-matching and the dangers. I think someone posted it on this forum?

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Are all pyrogen-equipped ematches friction- and/or impact-sensitive? What is the main reason they aren't made safer - is cost the primary factor, or is it difficult to make a composition that is sufficiently heat-sensitive without being sensitive to the others?

 

I wonder if it would be possible to make a safer ematch by exploiting the chemistry between the bridge wire and pyrogen - for instance by initiating a thermite reaction between the bridge wire metal and a pyrogen metal oxide. This reaction could in turn ignite a less sensitive composition that gives off flames/sparks.

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for instance by initiating a thermite reaction between the bridge wire metal and a pyrogen metal oxide. This reaction could in turn ignite a less sensitive composition that gives off flames/sparks.

 

That sounds interesting, maybe something using black copper oxide? What about this, just thinking here, maybe come up with a final coating of an inert non reactive substance to shield the pyrogen from contact with anything even lift granules? But will be burned away relatively easy enough to insure ignition of whatever it's igniting. Maybe a mix of dextrin and parlon thickened with water then dip the finished dried igniter in that for a medium thick coating covering all of the pyrogen and a little ways past. I'm thinking parlon with dextrin could make it more elastic and chip proof/crack resistant. Maybe?

 

 

 

 

@Sparx from my experience is is enought to just hot glue the lowering cord on after pasting (for a cleaner look wrap 'em up like a spanish shell or attach the loop before the last pasting and cover the glue with last pasting). Commercial shells often use just a circle of gummed tape with a hole in the middle. Glue on the string and cover with tbe circle. Up to 6" you won't need to run tne string around the shell (just maybe on heavy multi break cannisters).

 

Good idea about attaching the loop on the last layer of pasting using a disc to cover the tag ends. That way I can paste that area uniform with the rest of the shell for more even break or for good measure at least.

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The other thing you can do is keep the ematches shunted and the shrouds in place.

 

For my home show I match ~200 shells (all consumer) directly into the lift. I leave the shrouds in place, and don't put my body over the loaded guns. My display shells I do match into the leader once the shell is in the gun.

 

Kevin

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I did some research, and it turns out there are several exothermic reactions with metal that may be of use. Black copper oxide was also one of the first oxidizers I considered. I'd rather use a less reactive metal than Al or Mg in the bridge wire though, one that I know will not corrode over the years. And I believe the powdered CuO thermites, which could be used to coat a chemically (for our purposes) inert wire is friction and/or impact sensitive.

 

Using an inert coating helps for friciton sensitivity and chemical incompatibility, but a hard impact will transfer through the coating. My goal is something that costs little, works reliably and can take more abuse than current offerings without going off. Ideally it should be sensitive ONLY to the bridge wire itself reaching a very high temperature. In practice the pyrogen itself will probably also have to be flammable, but it can have a high ignition temperature and be resistant to shock, friction, water, common pyrochemicals, and static electricity.

I don't imagine I'll ever be the one to manufacture those ematches commercially, but it's still interesting to research and discuss, and it may come of use to someone sometime.

 

 

I found some especially curious intermetallic alloying reactions, which can in some combinations be strongly exothermic. They're analogous to the zinc/sulfur reaction. That one is not useful because zinc wire would be susceptible to corrosion, and the Zn/S powdered mixture is sensitive to static electricity.

 

One reaction is that between palladium and aluminum:

There's actually a product, called "pyrofuze", which uses this reaction. It consists of a palladium-coated aluminum wire, and when current is passed through it to heat it, the reaction begins. I've not been able to find any price, but it looks expensive.

 

The same reaction, though less exothermic, is possible between nichrome wire and aluminum. I saw a video of this years ago, but cannot find it. This would be less costly, nihcrome is already used for bridge wires, and it's chemically resistant. The question is if the reaction can be initiated with the voltages and currents we have at our disposal.

 

I had some difficulty finding any collection of these different intermetallic reactions. The closest I came was the book in the video above: Twenty-fourth International Pyrotechnics Seminar. Does anyone here have access to that book?

 

Now that I looked around some more, I actually found the paper itself: http://www.osti.gov/scitech/servlets/purl/658208

The seminar list may also be of interest: http://www.ipsusa.org/semlist.htm

Edit: and here's some more info, with free papers from some older seminars: http://www.intpyro.org/seminar.aspx

Edited by GalFisk
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Are you interested only in low-current igniters? If you can throw a couple amps at the problem a mix of graphite/Cu(II)O3 in NC, dipped onto duplex wire, will ignite just about anything, including Fe thermite. The composition forms the bridge, and the reaction seems to be thermitic (produces globs of molten copper) as long as current is maintained. It is not a pyrotechnic comp, however, will not burn, and is not sensitive to shock or friction.

 

Kevin

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In this case I'm interested in something that can directly replace currently used, potentially dangerous ematches. In that regard, it needs to compete in cost, reliability and convenience, fulfill all fire and no-fire parameters of the current commercial offerings, and at the same time be substantially more resistant ("immune" for practical purposes) to ignition by friction, impact, static electricity, and possibly also radio frequency energy, and maintain or improve chemical compatibility.

 

What are the actual fire and no-fire parameters for commercial ematches?

 

Thanks for the formula, it may be interesting for personal use if nothing else. What are the ratios of each ingredient?

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50:50 works just fine.

 

I can't speak to the orange chinese matches, but MJG J-Tek are no-fire at .3A and all-fire at .75A

 

I think you may be taking on a near impossible task. In order for the ematch to take fire from that tiny little 50g wire, you have to use a very sensitive compound for the first fire, then your pyrogen has to take fire from that. Even the consumer legal Firstfire matches are reported to take fire from friction - can't say myself as I haven't yet tried them.

 

Kevin

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I though about this a little more, and there is a way witch should be safe as normal matching.

Talon igniters cost nearly the same as normal igniters (if you buy a couple hundreds it's just 2 cents and the are cheaper in shipping), so about the same).

Just clip two strands of black match into the igniter and add it to the lift cup (of course twist the wire end) this way all of the sensitivity problem of normal e-matches should be solved.

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I'm probably going to use the Talons myself actually. The IR remote firing system I have is made for talons. They're however not a 1:1 replacement for commercial ematches.

 

Thanks for the fire and no-fire parameters. Do you know the voltage required or the resistance of these ematches? Pyrofuze at .002 inches may possibly match the firing parameters, but that is very thin stuff: http://www.sigmundcohn.com/pdf/EN/pyrofuze.pdf

 

And I don't know what the resistance is. Or the price. Or if the energy from this reaction is high enough to ignite a non-sensitive pyrogen reliably.

 

The perceived near-impossibleness of the task is what I find intriguing. I believe it is difficult because it has mostly been thought about in the traditional way - using an inert bridgewire (or a conductive pyrogen constituent) to produce enough heat in a short enough time to ignite a sensitive enough pyrogen. If it can be done in an alternative fashion, by involving the chemistry of the bridge wire itself, the pyrogen itself can possibly be made safer.

 

I may believe differently in the future.

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surely this has already been done

ie. development of a less sensitive ematch / fusehead

 

I believe foti and mjg both have ematches based on thermitic compositions, (to reduce the chance of accidental

ignition by impact and friction)

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The current ratings for Jteks are at 12v. The resistance with a 2m lead wire is in the 1.4-1.7 ohm range.

 

Kevin

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