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Idea for 9V Battery Ignition System

Posted: Wed Jun 13, 2007 8:30 am
by appleorchard
I saw a vid last week that showed how a 9v battery could ignite steel wool.

Got me to think that such a combo would be a reliable way to fire off my cannon.

I'm thinking of mounting the battery to the cannon, and running a couple of wires into the removable cap (chamber access point). At the ends of the wires would be alligator clips, with a bit of steel wool connecting in between.

I would then run the wires to a remote, push-button switch that would close the circuit and ignite the wool.

Steel wool is pretty cheap, and I think it would be a lot more reliable than a spark gap (which seems to fail more often than it works). Plus, the wires could be of such a length to put the steel wool out into the middle of the combustion chamber.

Has anyone done something like this? Any thoughts?

appleorchard
fond du lac, wisconsin

Posted: Wed Jun 13, 2007 8:52 am
by Spuddin
sounds like something worth trying, i have never been able to igninte steel wool with a 9v but maybe i was doing something wrong. let us know how it works out dude.
_______________________
www.freewebs.com/spuddin

Posted: Wed Jun 13, 2007 9:31 am
by appleorchard
Check out this vid...I think this looks promising!


Posted: Wed Jun 13, 2007 9:43 am
by Counterstriker
Yes, It works I just tried it its pretty cool.

Posted: Wed Jun 13, 2007 10:04 am
by Orpackrat
Spread the steel wool apart so it is not compressed and air get get tot the center an it will throw sparks

Posted: Wed Jun 13, 2007 11:50 am
by A-98
well, it might be really inefficient it use an whole clump. what i would do is take a few strands(4 maybe), bunch/coil em up or leave em as wires. this way you wont have the molten metal burning at your chamber, and you use alot less.

Posted: Wed Jun 13, 2007 11:59 am
by jimmy101
This has been tried several times. My understanding is that it is (1) hard to get the steel hot enough to ignite the fuel and (2) a PITA to change the steel wool for every shot.

Couple of links;
http://www.spudfiles.com/spudtech_archi ... steel,wool
http://www.spudfiles.com/spudtech_archi ... steel+wool

Posted: Wed Jun 13, 2007 2:48 pm
by appleorchard
Yeah, just a handful of strands is what I was thinking...I have to imagine those would burn just hot enough to cause ignition.

I'll be messing with it this weekend...I'll report my results. :)

(Although that second link above is making me wonder...)

Posted: Wed Jun 13, 2007 3:06 pm
by lukemc
i think an even cooler idea would be use a modifid cap gun

Posted: Wed Jun 13, 2007 8:55 pm
by singularity
i have a friend who tried it, modified a clean out to accept two small electrical clips which were connected to a momentary switch and a 9v battery. it made the iron wool burn but it didn't work at all. each time he put in about a fist sized clump of iron wool and nothing. your better off with a grill or butane torch igniter

Posted: Thu Jun 14, 2007 7:27 am
by appleorchard
Maybe a bigger battery? Or several 9v bats in series? Give it more of a spark?

I messed with model rocket engine ignitors at one point, but they're not the cheapest.

Posted: Thu Jun 14, 2007 7:32 am
by veginator
you could have a fan to help get air to it because steel wool needs oxygen to burn.

Posted: Fri Jun 15, 2007 1:39 pm
by Counterstriker
Ok this is how your do it. You have 2 alligator clips which is ran by the 9 volt, you get 1 strand of steel wool and put a the alligater clips on each side. run the current through and it burns safe!

Posted: Fri Jun 15, 2007 1:53 pm
by Pete Zaria
I used this exact ignition method on an aerosol combustion a LONG time ago (my first gun, I think. I was about 14, lol).
It didn't work very well. Even when the fuel/air mixture seemed right, it only ignited one out of every three or so tries.
A cheap BBQ sparker or even a flint lantern lighter is a better bet than steel wool and a battery.

If you need something you can use remotely, try making a camera flash circuit with 50ft of wire for the low-voltage relay that fires it....

Peace,
Pete Zaria.

Posted: Thu Jun 21, 2007 11:07 pm
by hoastmaster
how about a car spark plug??

ever thought of using one of them
i've never had a go at using one in fact i'm in the middle of designing my first cannon so mabye i should open a topic just for my spark plug theory?