The ignition system on a potato gun is usually the hardest part to get sorted so we've made this kit which has everything you need.

All you need is some basic soldering skills and 2 x AAA batteries. The 30,000 volt igniter module gives a strong continuous spark which is much more satisfying than the 'clack clack' you get from a pushbutton piezo igniter!

The electrodes suit a 100mm diameter Class D PVC pressure pipe combustion chamber. For smaller pipes just cut the electrodes to length so they meet in the middle. You could install this on a steel pipe but the electrodes would need to be insulated from the combustion chamber so the steel doesn't short out the spark.

WHAT YOU GET
1 x Pre-drilled custom made PVC housing
1 x Sinsui Electronic Igniter Potato Gun Ignition 30kV
1 x Battery holder (2 x AAA's) with on/off switch
2 x Electrode screws with brass rod inserts
2 x Electrode washers
1 x Pushbutton switch
1 x Packer foam

WHAT YOU NEED
2 x AAA batteries
Basic soldering skills
Soldering iron, side cutters, screwdriver etc

INSTALLATION INSTRUCTIONS
1. Install the pushbutton switch into the end hole of the PVC housing and do the nut up with long nose pliers, but not too tight.
2. Put 2 x alkaline AAA batteries into the battery holder and replace the cover.
3. Tape the battery holder to the top of the ignition module so it sits flat on top and the wires are at the same end as the red and black wires on the ignition module.
4. Cut the red and black wires from the battery holder and the ignition module so they are all 75mm long. Strip 5mm insulation from each wire and twist strands together.
5. Cut the blue wire and thick black wires from the output end of the ignition module to 150mm long. Strip 10mm insulation and twist the strands together.
6. Put the parts inside the PVC housing and hold it against your combustion chamber about half way along. Squeeze the housing so it holds the parts then mark the screw holes with a marker pen.
7. Drill two 5.5mm holes where you made the marks.
8. Put the washers on the electrode screws and loosely screw the PVC housing to the combustion chamber.
9. Poke the spacer foam in under the ignition module so that it pushes the battery holder firm against the top of the PVC housing. The battery holder on/off switch should sit in the centre of the 2nd hole in the top of the PVC housing. Trim the foam spacer if necessary to make everything fit properly.
10. Put the bare wires under the washers then do the screws up tight while holding the wire in place. If you don't want to get a shock put insulation tape over the screw heads.
11. Solder the red wire from the battery holder to one of the terminals on the pushbutton switch (doesn’t matter which one).
12. Solder the red wire from the ignition module to the other terminal on the pushbutton switch.
13. Make sure on/off switch on the battery holder is off.
14. Twist the black wire from the battery holder and the black wire from the ignition module together, solder and cover with insulation tape or heat shrink tubing.
15. Adjust the gap between the tips of the electrodes to about 10mm.
16. Switch the battery holder switch to on and press the pushbutton. You should get a strong continuous spark. If not check your connections, the batteries, and the spark gap.

ABOUT POTATO GUNS
Despite what a lot of people think potato guns are NOT illegal in New Zealand but you do need a firearms license to own and use one (a bit of common sense helps too). This applies to combustion type potato guns, i.e. the sort that use deodorant, hairspray or similar gas fuel. Because they make an explosion (like the gunpowder in an ammunition round) to propel the projectile they are technically classed as a firearm.

NOTES
Potato gun not included.
If you want to make one Google it.
Don't use DWV pipe, it's not pressure rated!