Where to place ignition?

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xzenir
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Tue Apr 01, 2008 9:17 am

hey guys, i'm building a hybrid and I was wondering what the best place could be for an igniter.
Tapped in the chamber is not an option, since I don't want any holes in in xD.
Maybe in a T-pipe at the end of the chamber??
All help is welcome :)

thnx.
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MaxuS the 2nd
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Tue Apr 01, 2008 9:21 am

The center of the chamber is the best spot as it allows the flame front to the gases more efficiently. What about sleeving a coupler over the chamber and tapping that. Many people have tapped the chamber before and it seems to work well.
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scottcrete
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Tue Apr 01, 2008 9:22 am

from what i undersand the best place for this to take place.. is in the center of your cumbustion chamber.. so with that being said.. i would mount your ignitor anywhere you want it.. then run the wires into your combustion chamber and place them where they will be in the center.. when drilling in your combustion chamber make sure you use a bit the same size as your wire and put epoxy on both sides of the wire to prevent eroding of your pipe from shots..
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bigbob12345
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Tue Apr 01, 2008 9:24 am

well you should probably search before posting a topic like this one but your new so...

the best place for the ignitor is the middle of the chamber it may not make sense at first but it will give a tiny bit more power.
but the way to attacth it is to get a tee, a bunch of bushings, and make a spark plug. An easy way is to just epoxy the wires leading from your ignition to a small plug(1/2in, 3/4in)and set the gap.

And welcome to spudfiles :D

Edit: I type to slow, got beaten by maxus and scottcrete
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psycix
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Tue Apr 01, 2008 9:28 am

In combustions the spark gap placement is more important than in hybrids.
The burst disk makes up for bad placements and the difference is not as big.
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xzenir
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Tue Apr 01, 2008 9:28 am

we'll i've searched the forum for my answer, but didn't found any answers.
now i have xD i think i just use a spark plug and mount it in the middle of the chamber.
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Hubb
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Tue Apr 01, 2008 9:42 am

http://www.spudfiles.com/forums/a-few-h ... rt,15.html

Check out the fifth post down. I had the same problem when I built my hybrid and I did not want to tap into the side of the chamber. The above pic should help you out. It is very easy to construct.

When I built my hybrid, I changed it around a little, but it will give you a general idea of how I placed my spark in the center without tapping a hole in the chamber.
xzenir
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Tue Apr 01, 2008 9:57 am

aah thnx,, images can say more than words !:P
now I should be able to make a nice ignition on my gun xD
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Hubb
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Tue Apr 01, 2008 10:10 am

Instead, check out the How-to I just made. It should help even more. Any questions on it, just ask.
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rcman50166
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Tue Apr 01, 2008 10:22 am

Well this seems like a good question to ask in the sparker reference guide instead of a new thread.

Answer, by the way, is in the center. However if no holes are allowed it makes it pretty challenging. Ther has to be a hole somewhere. The best solution, if no holes is a requirement that has to be met (which I doubt it is), is to use a remote control servo ciruit. Not cheap but it's the only way with no holes in the chamber. If you see this as the only option just private message me for instructions.
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STHORNE
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Tue Apr 01, 2008 10:23 am

Great job on the "How to" hubb017. wouldn't you want to shorten them and place them towards the center of the chamber on the side at a 45 degree angle for better performance?
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Hubb
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Tue Apr 01, 2008 10:26 am

In my launcher, the spark is placed in the center. It is in the direct center. It took several pieces of coathangers to get it this way, but it works wonderfully, AND I didn't have to drill into my chamber, compromising its integrity.

As far as the angle goes, that would be kind of hard to accomplish with the small cap, but I bent the tips at an angle. Does that count?
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STHORNE
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Tue Apr 01, 2008 10:40 am

oh, i see...you just extended the coat hanger's until you got the spark gap to the center...my bad.

and you could just bend them to get the 45 d angle to prevent non intentional sparks. but its not neccessary, it would just help a little. anyway, i like your design, just didn't get it at first.

good job.
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Hubb
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Tue Apr 01, 2008 10:41 am

I did bend it. The tips are bent closer to keep the spark at its tip.
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STHORNE
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Tue Apr 01, 2008 10:48 am

ok. what are you using for ignition? piezo or s.g.?
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