Wire Pull Ignition

[Scttgrffths21]

Hello gents, I make homemade smoke grenades for my friends to use playing paintball in our back woods. I've found a composition I like, i use mortar tubing with clay caps to keep it cold burning, but I have one last hurdle... Many commercially available smoke grenades (even super cheap firework ones) have a wire pull ignition. Some grenades you have to pull the wire straight down (though its coming out f the top), others have you pull at a 90 degree angle. I bought a couple and opened them up, but all I see is a string. Me = confused. Anyone know these works?

[Ubehage]

On those fireworks-strings that you pull, and it goes *CRACK*, there is a small amount of Armstrong's Mixture. I don't know if other igniters work the same way.

 

Armstrong's Mixture is an extremely sensitive and highly-explosive compound. It can be bound with "something" (maybe acetone?), which will keep it somewhat stable. Although, still extremely sensitive to any friction.

 

Besides that, would you care to share your smoke composition?

[MrB]

I cant help but feel it might be safer to use a match-head, and some striking paper on the end of the string. Armstrong's mix scares the crap out of me, personally.

B!

[Scttgrffths21]

Interesting... Does the mixture need a striking surface though? Or is the friction of dragging the string enough to cause it to ignite?

 

For my smoke compound, I'm using 60g potassium nitrate, 40g sugar, 36g parrafin wax. Started at 40g for the wax too but kept getting left with extra after mixing.

[BurritoBandito]

I wouldn't reccomend making Armstrong's mix unless you're prepared to pay the consequences of accidental ignition. Kurt Saxon (author of "Poor Mans James Bond") lost part of his hand while attempting to mix this stuff up with a spatula. (no comment)

 

"The resulting blast kneaded the spatulas out of shape. It atomized the first 3/4 inch of the bone handle and split the rest. It shattered the plastic mixing bottle. The fingers holding the bottle had the flesh blown off the bones and the bones had to be amputated. The palm of the hand was turned into hamburger and its inner bones were smashed. The hand holding the spatula was undamaged except for particles of the plastic bottle which pierced the skin." -Kurt Saxon

[Ubehage]

As I said, it is extremely sensitive! Propably the most dangerous stuff to make, and also one of the most powerful explosives.

 

But to answer your question: Yes, it will go off by pulling the string. No extra friction needed. It will propably even go off, when you enclose it with the string, due to the extreme sensitivity.

 

It is the same stuff that is used in percussion-cappers.

If, and I mean IF, you choose to experiment with that shit, I suggest getting a bunch of these, instead of making the mixture yourself.

 

Never keep more than 1gram at a single location, unless you actually plan to die of an accident.

Edited September 5, 2014 by Ubehage

[Scttgrffths21]

Thanks for the info and warnings... I don't know if I even want to mess with that stuff. There must be less volatile ways. I can't imagine the strings on the fireworks they sell to kids are covered in that stuff. My friend bought two cases of pull string grenades, and if the commercial ones use that mixture, then you're essentially telling me he's got a bomb sitting on his coffee table and with the right vibration he might detonate the whole thing? Something isn't adding up. There shouldn't be an explosion.. That's far more volatile then I'm looking for. I just want to create a flame. Im using matches and a fuse right now, but surely there's middle ground between that and a mini-hiroshima.

[BurritoBandito]

You'd be surprised at some of the compositions used in children's toys. Party snaps, cap gun caps, those pullstring poppers, etc. all have tiny amounts of pretty sensitive explosives in them.

I second MrB on the suggestion to make ignitors from matchbooks. There are also methods for making ringpull ignitors that use a compressed spring to slide a match over a striking surface. Whatever route you choose to take please be very careful.

 

Edit: This thread may interest you.

Edited September 6, 2014 by BurritoBandito

[MrB]

Digging down through the links in BB's link i ended up looking at pretty much what i imagined for mastheads & striker paper on a string. It's so similar that i almost have to had seen that thread, and stored it somewhere in the back of my mind. Anyway, thats what i use when i need a "pull" igniter.

 

The fancier copper coil on a key ring solution i never cared much fore, they always seam to need compositions with chemicals i never have access to. I'm sure they are great, reliable and all, but matchbooks are free at almost any bar...

B!

[Scttgrffths21]

I made pull ring grenades by embedding my fuse and a match inside my canister and then rubberbanded/taped a strip of the strike side of the box and connected it to a paperclip/pull ring. The problem with that method is the port for the strip of strike surface to pass through leaves too big of a diameter, and I can't consistently keep the burn to a smolder. I occasionally get flame throwers or ones that sputter flame, ands that's no good.

I figured that the string method would allow a smaller port, less oxygen, and thereby less chance of flame.

Perhaps I'm not familiar with the method you're speaking about.

[BurritoBandito]

Why not just attach the ignitor outside of the casing?

[Scttgrffths21]

I'm aiming to have it be "cold burning", and let produce any visible flame. We play in the woods and don't want to risk a forest fire.

 

I just read through that thread, thank you. I have some party pop things... Just failed my first attempt to light a match with it. Interesting ideas.

[BurritoBandito]

Something like this could work if the cap was "glued" into place with some pyrogen. It is very similar to the one I was talking about that slides a match over the striker using the energy stored in a spring. The only difference is that they substituted the match/striker with a nail/cap. Honestly it's probably a better design.

[Mortartube]

Some wire and string pulls have a piece of kinked wire that pulls past a small pistol primer. This explodes and ignites a pressed BP layer which in turn ignites the flare or smoke in question.

[FlaMtnBkr]

I doubt it is a pistol primer. For one it would be a bit violent and it is encased in metal with a metal anvil covering the comp. A wire would not contact what it m needs to.

 

They do use a small pellet with a hole in the center. The composition has been discussed here somewhere but obviously needs to be sensitive for a wire to cause ignition.

 

There is a tutorial here about making a pull string igniter with a small tube, match heads and a string loop glued to a striker. This is probably what I would go with or a variation.

[LiamPyro]

I too have been trying to make pull cord igniters. I am still perfecting it, but this method has worked well for me: First, carefully remove the small charge (the thing with the string that goes "bang") from a party popper, and unroll the small paper cylinder until you have almost reached the core where the string and explosive composition are. Next, pour a small amount of meal-D black powder or crushed match heads onto the unravelled paper next to the string, and roll up about a half inch or so of paper and tear off the rest. Secure the paper with a tiny piece of tape or a dab of superglue. I haven't completely worked out how to do the next step yet, but what I suggest *should* work. What you want to do is to roll a small paper tube with an inner diameter of about 3/8" or 1/2" and cut it to about 3/4" long. Cap one end of the tube by glueing on a small disk of thin kraft paper, and then poke a hole in the side of the tube near the capped end that can fit the string, but not the small charge. Feed the string into the open end of the tube and thread it through the hole, then gently pull the string through until it is stopped by the cylindrical charge. Fill the tube around halfway with some sort of easily ignitable yet fairly mellow burning mixture such as black powder based fountain mix and insert a fuse and some tissue paper to hold the composition and fuse in. Alternatively, you could place a thin piece of tissue over the fountain mix and then fill the rest of the tube with smoke bomb ignition-mix. Insert the bottom of the tube into the top cap of your device and glue it in, and you're ready to go!

 

Hope this helped! Be safe and have fun! BTW if you don't quite understand this, I can post a photo of a diagram to help.

[dagabu]

I too have been trying to make pull cord igniters. I am still perfecting it, but this method has worked well for me: First, carefully remove the small charge (the thing with the string that goes "bang") from a party popper, and unroll the small paper cylinder until you have almost reached the core where the string and explosive composition are. Next, pour a small amount of meal-D black powder or crushed match heads onto the unravelled paper next to the string, and roll up about a half inch or so of paper and tear off the rest. Secure the paper with a tiny piece of tape or a dab of superglue. I haven't completely worked out how to do the next step yet, but what I suggest *should* work. What you want to do is to roll a small paper tube with an inner diameter of about 3/8" or 1/2" and cut it to about 3/4" long. Cap one end of the tube by glueing on a small disk of thin kraft paper, and then poke a hole in the side of the tube near the capped end that can fit the string, but not the small charge. Feed the string into the open end of the tube and thread it through the hole, then gently pull the string through until it is stopped by the cylindrical charge. Fill the tube around halfway with some sort of easily ignitable yet fairly mellow burning mixture such as black powder based fountain mix and insert a fuse and some tissue paper to hold the composition and fuse in. Alternatively, you could place a thin piece of tissue over the fountain mix and then fill the rest of the tube with smoke bomb ignition-mix. Insert the bottom of the tube into the top cap of your device and glue it in, and you're ready to go!

 

Hope this helped! Be safe and have fun! BTW if you don't quite understand this, I can post a photo of a diagram to help.

 

You really don't want crushed match heads in any kind of confinement, like smokeless powder, they will deflagrate and over-pressure your device. A glustaz type mix is much better for this kind of ignition.

[BurritoBandito]

Also, I'd be very careful unwrapping the party poppers. It doesn't take much to set them off, and while I doubt it would cause any serious injury, I'm sure it would be unpleasant to pop one between your fingers.

 

Dag, your link just pulled up a search that displayed this:

"One or all of your search keywords were below 3 characters or you searched for words which are not allowed, such as 'html', 'img', etc, please increase the length of these search keywords or choose different keywords"

A separate search on APC only pulled up two threads with te term glustaz. This being one of them, and the other only mentioning it as a potential prime. A google search also only returned two results. The first is not related to pyro, and the second is the same thread mentioned above briefly discussing it's potential use in a matrix comet. I'm unfamiliar with this term. Would you mind elaborating a bit on it, or giving me a point in the right direction, so I could research it for myself? Thanks.

Edited September 8, 2014 by BurritoBandito

[Mumbles]

Danny Creagan has a page about it, and should cover most of your questions.

 

http://www.wichitabuggywhip.com/fireworks/glusatz.html

[BurritoBandito]

Thank you Mumbles, but I am receiving a 404 error on that link. Going up one level to the fireworks directory and searching for "glustaz" yields no results either.

 

Edit: Found it. There was an additional %C2%A0 at the end of the URL that needed removed, and my searching failed, because I miss-spelled it "glusTAz" as opposed to "glusATz. Thanks.

Edited September 8, 2014 by BurritoBandito

[Scttgrffths21]

Thanks for all the tips everyone.

Burrito Bandito, I've seen that spring/pin/cap method before, but I dont understand how to turn that into a way to light my fuse reliably. It would seem I'd need to add an accelerant of some kind, and that expertise is why I'm here - I put the amatuer in amatuerpyro.

LiamPyro, that's an interesting design. I'm a very visiaul person, so if you could post a diagram that would make a world of difference for me. Much appreciated!

Mumbles, thanks for the link. I read through glusATZ and I'm a bit confused. For the application I'm drviing at (string pull ignition)... how does this stuff come into play?

[dagabu]

Thanks for all the tips everyone.

 

 

...Mumbles, thanks for the link. I read through glusATZ and I'm a bit confused. For the application I'm drviing at (string pull ignition)... how does this stuff come into play?

 

 

 

I think that was from me. The Glustaz is a very slow burning comp that will give heat over a longer period of time allowing for ignition of a hotter comp that will give the heat that is needed to ignite a hard to light comp like sugar mix (dew and moisture make it hard to light or through the wax coating one puts around a grain after its cast) and does not deflagrate viciously like BP or ground match heads.

[Mumbles]

Fixed the link. The forum software seems to add in spaces occasionally when parsing links.

[Scttgrffths21]

My apologies, Dagabu. Thanks for the info.

I have cannon fuse that once embedded into the mixture has no problem igniting it. I figure all I need to do is light the cannon fuse.

The thing that's not making sense to me with the glustaz is that its a slow burning compound, but I just need something that burns hot for a second (enough to light the fuse), and then I want it to go out. The glustaz said it burned at 14 seconds per inch. The application I want to use this for is a pull pin for a smoke grenade, so waiting 14 seconds after pulling the string for ignition is quite a bit long.

 

Are you stating the glustaz option may be superior to a pull string method in general? Sorry for the confusion.

[Scttgrffths21]

Here was my lame attempt last night to replicate the party popper concept. As you'd probably imagine, pulling the string went "bang" and nothing else happened. I feel I need a compound and device connecting the popper to the fuse.