Sparker and ignition problems.

[jimmy163]

I have been using a piezoelectric clicker out of an electric lighter. The spark is enough to ignite but it stops working after 1 combustion due to it getting so wet.

I was thinking about a BBQ ignitor but they are also piezoelectric and I assume they will suffer from the same problems?

I was looking at the camera flash sparkers but they look to technical and high voltage for me.

I read that the lantern lighters also become useless when wet.

Are the BBQ ignitors good enough? And where can I buy one in the UK?

Thanks

[TurboSuper]

"wet"? What the heck are you sparying in there?

[jimmy163]

Any aerosol. Right Guard, Hairspray. It all goes wet.

[sputnick]

Um, water would ot stop a spark, if anything I would think it would help... how large is the gap? because if it is super small I would guess that it is because the liquid is filling the gap, I'm not sure if that's capillary action or something to do with surface tension, bur that could be the problem.

Can you get a pic up of the configuration? outside and inside?

[jimmy163]

I think from what I have tried and read, is that these sparkers are not reliable enough.

I now want to install a lantern flint sparker. Going to ring round the camping shops tomorrow, but it seems that these are more of an American thing.

Anyone know where I can grab one here in the UK?

Thanks!

[Ragnarok]

Um, water would ot stop a spark, if anything I would think it would help.

Most likely, if there's a problem it'll be moisture forming a path of lower resistance across the chamber wall, not anything in the gap.

[TurboSuper]

You should place the electrodes at the back and try not to spray them directly, push the can in a little. Use a chamber fan to ensure an even mixture.

Basic BBQ sparkers work wonderfully, btw.

[psycix]

Keep em clean by not spraying directly on em, and by using something else instead of hairspray.
Also I have the feeling that your gap is not close enough. A good gap is UNDER 1mm.
BBQ sparklers are indeed very reliable.

[jimmy101]

If you are actually wetting the inside of the chamber (and the spark gaps) you are using way too much fuel. The liquid fuel load for a typical combustion gun is only a drop or two of most fuels. That amount of liquid from an aerosol can should evaporate inside of the gun in a few seconds at most.

Drop the fuel load and wait a while before firing, everything in the aerosol can that is a liquid will evaporate. (With things like RightGaurd there will be some solids that won't evaporate.)

A chamber fan will help to not only get the fuel to evaporate but also help with mixing, combustion and venting.

[jimmy163]

I was doing some more tests. Even using a plastic bottle as a small scale test, the spark takes a few tries to ignite the fuel.

I don't really think its up to the task of being reliable. Tomorrow I will be building a camera flash ignitor.

I've built my own Hi-Fis and such before so this shouldnt be too hard.

[psycix]

If you can see the spark, then it is powerful enough to ignite. If you see a spark but it doesnt ignite, then there is something wrong with your mix: the amount of fuel. As a rule of thumb: when people are new and have fuel problems, they are adding WAY too much fuel (up to a factor of 10 times too much)
The reason it does ignite after a few tries is because the fuel will have some time to disperse, fly away and mix with the air giving you a burnable mix.