Page 1 of 2
spark consistency
Posted: Sat Dec 29, 2007 12:00 am
by carter
I have been looking into building a hybrid. i currently have a pneumatic marble gun, have build a 200psi 3/8 spud launcher using all galv piping. also have made one combustion launcher using hairspray.
more to the point i'm sick of pumping so i was going to design and build an advance combustion but i got into thinking. why not go the hole hogg and build a hybrid. so i will. i'm soon to be getting $500 from the government for completing my first year as a boilermaker. so the money is there.
i just need to no a few things.
one: how consistent are bbq sparkers. will they fire the cannon every time?
second: to the aussies, can we get stun guns in aus?
third: will it fire every time if i can get my hands on one
i want it small. something under 2liters. all steel and portable. but happy to sacrifice those in order to make it work.
Posted: Sat Dec 29, 2007 12:05 am
by benstern
You can not use a bbq sparker for hybrids. They will not work under the pressurized environment present in a hybrid.
On a side note.... what happened to the days when we would say that people who ask questions about hybrids should not make them.
Posted: Sat Dec 29, 2007 12:05 am
by paaiyan
As for the bbq sparker, I wouldn't suggest it for a hybrid. The distance the spark will jump is inversely proportional to the amount of pressure in the chamber. Double the pressure, half the spark distance. I don't know if you can get the stungun, as I'm not an aussie, but I do know that in some places where you can't get a stungun, you can still get the circuit.
EDIT: benstern, well, I feel safe answering this question because he says he's a boilermaker, which means he's got some knowledge he can apply to this. And he didn't phrase it in noob-speak.
i.e. "im gunna mak a hibrd canon and i need help what parts do i ned nd hwo do i mak 1??!!"
Posted: Sat Dec 29, 2007 12:14 am
by carter
i'm no noob. i'm getting info so i can hopefully solve problems before they start. i'll try gain more info on stun guns.and have a really good look at camera flash. but more to the point. under pressure will it fire verytime i hit the trigger?
Posted: Sat Dec 29, 2007 12:16 am
by paaiyan
I didn't say you were a noob, quite the opposite in fact. As long as you're getting a spark, and your mix is good, it will fire. For that spark, You want to see how far apart you can get the electrodes while still getting a good spark, then make sure you adjust for the pressure environment. 1/3 the normal distance for 3x the pressure etc.
Posted: Sat Dec 29, 2007 12:20 am
by carter
sorry. it was more to what benstern said. i take your comment as a compliment. with the spark. is there any improvement in changing the spark gap per mix level? i could think of a few good systems to combat that.

Posted: Sat Dec 29, 2007 12:24 am
by paaiyan
What do you mean changing the spark gap per mix level? If you mean making the longest spark possible, I probably wouldn't bother with it. Set the gap so that it wil spark consistently at the highest mix you'll use, then leave it there. Yea, you could get a longer spark out of it at lower pressures, but I wouldn't bother with it, if your mix is good, you'll get a shot.
Posted: Sat Dec 29, 2007 12:28 am
by carter
cool. ill leave it at the highest mix. also thanks for the constructive answers paaiyan
i'm lucky to no pressure ticketed welders and should have supply to some some due to changing employers
Posted: Sat Dec 29, 2007 12:30 am
by paaiyan
No problem. I'm certainly not the most knowledgeable about hybrids on here, but come back with any more questions and if I can't answer them, I'm sure others here can. I wish I could build a hybrid, but I be poor.
Posted: Sat Dec 29, 2007 12:33 am
by carter
my only real problem is finding a good C:B ratio and ignition source. besides that i'm pretty much set to draw plans.
Posted: Sat Dec 29, 2007 12:35 am
by paaiyan
Well for the ignition you can find out about those stun guns. PM MrCrowley, he's in NZ but he'd probably know. Then you've got camera flash ignitions, flyback coils, inductor coils. I plan on building the latter, though the construction process consumes an inordinate amount of time.
Posted: Sat Dec 29, 2007 12:39 am
by carter
ye i'll try mc. i want to have the plans ready hopefully by mid jan. construction soon after. though i no it will take longer

Posted: Sat Dec 29, 2007 12:57 am
by SpudBlaster15
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Cras nec placerat erat. Vivamus dapibus egestas nunc, at eleifend neque. Suspendisse potenti. Sed dictum lacus eu nisl pretium vehicula. Ut faucibus hendrerit nisi. Integer ultricies orci eu ultrices malesuada. Fusce id mauris risus. Suspendisse finibus ligula et nisl rutrum efficitur. Vestibulum posuere erat pellentesque ornare venenatis. Integer commodo fermentum tortor in pharetra. Proin scelerisque consectetur posuere. Vestibulum molestie augue ac nibh feugiat scelerisque. Sed aliquet a nunc in mattis.
Posted: Sat Dec 29, 2007 9:53 am
by mark.f
Benstern, I have used a cheap Aim n' Flame piezoelectric igniter to ignite pressurized mixes before. A BBQ sparker will work fine for a hybrid, unless you do something stupid like make a 1/4" long spark gap in the cannon.
Posted: Sat Dec 29, 2007 10:33 am
by Novacastrian
markfh11q wrote:Benstern, I have used a cheap Aim n' Flame piezoelectric igniter to ignite pressurized mixes before. A BBQ sparker will work fine for a hybrid, unless you do something stupid like make a 1/4" long spark gap in the cannon.
Just to rub it in a bit more i use a BBQ ignitor for mixes up to 8x in my mini hybrid. The spark gap is around 1.5mm.