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Blaf

Bridgeless matches

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I don't know if any of you guys ever tried to make bridgeless matches but I have. And it was a success I might humbly add. They were graphite based ones with nitro-cellulose+meal coating and they work perfectly. Much before I came accross the know-how on Mighty Net, I used to make my electric igniters with steel wool wrapped around copper wires...which is tricky stuff to do and not reliable as those graphite ones are. In addition, as a power source I started using CDU (Capacitive Discharge Unit...or Flash Unit) which I took out from an used photo-camera...simple circuit which gives a lot of power from a single 1,5 Volt battery. The only shortcoming is that you can fire one firework at a time, but I don't really care.
Anyone interested in details?

Blaf

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Go to brainfever his site, bridgeless eletrical igniters, i make them to for firing aerial mortars and stuff, very reliable and easy to make,

Blaf are you sure 1.5 Volts is enough?
I use 12 volt over a distance from 20-30 meters

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Well, I have a wire some 20 meters long and it works like there's no wire at all. The clue is in CD-Unit which charges an electrolytic capacitor to few hundreds of Volts (Yes, from a single AA 1,5 Volt battery through a suitable electronic circuitry) and at a stroke of a switch, discharges it in microsecond! Experts say that power wires could be much longer and thinner(!!!)...they even mention hundreds of meters. I never tried it, though. So, with 12 V source you have to consider conductors lenght and surface to maintain the triggering current at certain level...but with this little CD-Unit it's simply not an issue...

Blaf

p.s. I'll try to recall where I found this on Mighty Net and post a link later...

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Pk you're right, I did it the same way with one difference - I made a small plastic box where the unit was then installed and added a main switch, charge switch and fire switch. A small red LEDiode was already there so I just drilled a hole in my box so that I have visual controll over charging. And one last difference - I never tried to use it on humans...which is I admit, very interesting idea...

Blaf

p.s. Hay, I'm just kiding!!!

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Hello guys

I decided to enrichen a bit all this jazz about bridgeless matches by posting a few images so that nobody could say I didn't try to do it myself. And here we go...

First, a small batch of bridgeless matches...they're set on a piece of white paper for detailed viewing. Left ones bear dark black heads - these are ordinary ones which pop more or less silently. On your right there are a few with silverish heads...they're treated with final layer made of Al-powder + NC lacquer mixture and they give more spark and louder POP. Reliability? 100% so far...
' alt='' class='ipsImage' width="1000px" height="750px"> target=_blank>' alt='' class='ipsImage' width="1000px" height="750px"> width=360 border=0>href>

And second, my little Capacitive Discharge Unit nicely packed into small plastic box. Box itself is hand-made from grey ABS plastic, glued with Acetone. OK, I did not make any CD electronic....I just took it from disposable camera and fitted it into my box. Main switch i on your right and flush with side pannel. On the left is front panel with + and - sockets and one chinch socket...that's where I connect my feeding-wires. On top side is a little "charge-on/off" switch, monitor lamp and main "FIRE" press switch. It's white...so what? It was the only one available in my junk then...OK, I admit, the red one would fit much better. Back side is not visible and has only battery compartment door. For now, this little gadget worked perfectly...
' alt='' class='ipsImage' width="1000px" height="750px"> target=_blank>' alt='' class='ipsImage' width="1000px" height="750px"> width=360 border=0>href>

Hope I did everything OK....if not Gamekeeper, do everything needed, please.
Suggestions as well as questions are welcome as always...

Blaf

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Yes, you're right Gamekeeper - they're graphite based ones. I should have placed a coin or something along them for size comparison and then take a photo... Graphite comes from dry battery cells and it's been powdered by scratching graphite electrode with a knife edge. Simple but effective way to get a small quantity.

Thanks for providing that "image resizing" code line! It really works!

Blaf

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I have another question for you Blaf the graphite you use is from dead batteries you say but is it possible to use the graphite from pencils if you make a fine powder of it because i have a bunch of those graphite sticks for in reusable pencils.
I read on brainfever his site that he makes a slurrie of graphite with nc laquer and then he dips his wires into the slurrie.
And after that dries a bit he dips it in a pyro comp for example bp wit water and dextrine and finaly he dips it in pure nc laquer to make it waterresistant.
Is that also the way you do it or do you have another technique.

Pirate

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Yes, that's pretty much the same procedure I use. And I found this idea somewhere on Net and just implemented it...what's the most important - it works.
As for graphite electrodes from used batteries - if you decide to use them, take them out and first burn out any parafine content inside them... they're soaked in it somewhere in their production.
Regarding your idea to use graphite sticks for pencils, I don't really know if they're pure graphite enough for this purpose...sorry.

Blaf

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Thats always good to know that it works. :wink:
Thanks for the tip on burning the parafine out thats gona be usefull.

Well long ago when i still was in school we used to scrape of graphite from our pencils and we made lines from about 5 cm and then we put 220 v on both ends of the line.
And it conducted nicely and burned up you could see all of the inside of the line get hot and red because of the generated heath the only problem was that our teacher didn't like it that much it kinda smelled and left a black mark on our piece of wood
So ill just try it out and post the results here

Pirate

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:D

I don't know how you did connect it, but 220v is a deadly voltage, I've once had a shock from 220v, that was NOT nice...

it took me almost 30 minutes to completely calm down...

so please watch out when handling those voltages and amperages.

and.. the graphite will also heat up at 12v :wink:


my bridgeless matches ignite in less than 0,5 sec at 12v

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Stijntje, Mr. Pirate was just descripting a harmless conductivity test of Graphite, that's all. They do that sometimes in high school...
As for my matches, they're set off by Capacitive Discharge Unit from disposable photo-camera. Voltage it delivers (in that important millisecond) should be around several hundreds of Volts. I also tested them on 12V car battery....they go off almost instantly as well.

Blaf

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It was indeed a test or somthing you do for fun on school but i know i dont have to use 220v for the EBW's.
And 220 v doesn't feel nice when you get it through your hands i know also when we where testing our graphite we had to make electric constructions nothing difficult or so but we had to do it in groups of 2 and somtimes youre partner plugded in your jack and then when you got hold of the wires wich you wanted to connect you jumped :D but exept for some pain in youre elbow for 30 min there wasn't no real problem.
But you do have to be careful when handling heavy voltages when your sitting behind a desk like we where it isn't such a problem but if youre on a ladder high above the ground its a different story.

And yesterday i alyet collected some graphite from those reffilings for a pencil but it did take langer then i thought so ill have to scrape some more tonight.
Or i can go take a look at some artshop because on brainfever's site he said that he got his graphite in an alyet powdered form there but that probably will be expensive so ill scrape some more.
And Mister Stijntje what kind of graphite do you use also from batteries or from pencils.
And how i conected is was easy i made a line of graphite about 5 cm and between 0.5-1cm withand then you have youre + and - wire and you put one wire on one end of the line and the other on the other end thats it.
Probably if you try this at home youre fuse wil burn out or switch of and it wont work but as i said it was at school and they where used to have shortcircuits so i guss they put in some high amperage fuses so they didn't had to change them all the time when sombody was teasing his working mate.
But if i think about it now that would be way to dangerous if they did that so maybe they had another technique but i never had it that we where without electricity there.

Edit: Blaf please dont cal me Mr Pirate just Pirate is more as enough then i start feeling as a gentleman and that just aint right :D but thanks for the honour.
And im also gona take a look around normaly i have some old junk fotocamera here where i can take the flashunit off any special things i have to wach out for as i do that Sir Blaf.

Pirate

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He, he, he...I knew you would react to that Mr. somehow. I did that so to distinguish you from other pirates around.
To get your disposable photo camera, just go to nearest photographer and ask for one already disposed. They'll gladly give it to you...and what's interesting, you usually get one 1,5V alcaline battrery inside for free. You'll need one in your CD unit, of course.
The only thing you should be cautious with are open copper terminals on CD unit...you'll see it yourself and probably discover it the hard way. Don't be scared, you won't drop dead immediately, it will take years...

Blaf

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Ah so you wanted to distinguish me from the other pirates wel euh then you can call me pirateA or somthing but Mr is to much honour for me it makes me feel unconfortable :D
Ah thats a good tip for getting a free camera and battery thanks im gona try it this afternoon.
And about those copper terminals if i just remove the batery first there wont be so much of a problem right ?
Il just try it and see what happens if you guys never hear of me again thanks for al the help so far and see you on the flipside :cry: :wink:

Pirate

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Just watch out for open terminals around electrolitic capacitor on the board. You know what, try to type "Capacitive Discharge Unit" in Google and it should yield guidelines through assembling process...

Blaf

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Ok il do a google search on the topic and ill be carefull when im working with the thing.
Edit: I just whent to the photographer and got myself a camera with flash.
Its only a pitty that our economy aint that good so everyone is trying to make some money so i had to pay 1 euro for it and they didn't give me any batteries with it but il manage.

Pirate

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And Mister Stijntje what kind of graphite do you use also from batteries or from pencils.

I've found a small bucket of graphite powder somewhere in my house :D
it's very fine, it takes long till it drops down if you blow some in the air..

the only thing I see on it is:
Graphite Pulver
B.V. Chem fabr.
P.O. Box 86
Schiedam
Holland

and there is a picture of a key on it, do you know uses of graphite pulver that have to do with keys?

and please don't call me Mister :D
there is a reason I didn't write the "mr." in my nickname with a capital :wink:
since I'm 14 years old, I'll be one of the youngest members here..

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The key sign could indicate that this particular sort of graphite could have been used as key-lock dry lubricant. Sometimes I use graphite grease to make my guns action work smootlhly...
Try conductivity test as Pirate previously described...but use lower voltage.

Blaf

p.s.OK, no more Misters...

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Sounds normal to me. If you stick your probes closer resistance should drop down... Make thick mixture of it with NC lacquer and coat open ends of two wound insulated wires and you're in the game. Leave it to dry and then make resistance measurement...it should drop down considerably. Which would mean - the powder you have is OK.

Blaf

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that's nice to hear, I have only made them with another binder, don't have NC lacquer..
whit that binder I use, they never stay for long, almost always break while drying..

well, the powder was bought at a large store (those where you can buy metal, wood and woodworking things, don't know the name of it)
I asked it my dad :D

I hope you can use that information

gr.
Stijn

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