Magic Forest- Butane Bazooka Biro

Butane Bazooka Biro

Introduction

This little baby was an off shoot of the trigger for spud launcher and was really just a muck around when I was bored on Sunday 19th November 2006. All I wanted to do is see if I could get a

PLEASE NOTE THIS IS VERY DANGEROUS. ADULT SUPERVISION IS REQUIRED AT ALL TIMES

The Challenge

Using a piezoelectric gas cookerstarter todesign a mini bazooka that would fire a projectile using butane gas as a propellant

Constraints

£0.99

Items used

Recycled piezo-electric gas cookerstarter
Bic™ Biro
1 map pin
Butane gas from gas cooker lighter
Open space

Build Time

Total time 10 minutes

Method

Take the piezo-electric gas cooker lighter and with a little care pull it to pieces and lay out all the items in a clean and tidy area. A little care should be taken as there is self-pressurized butane inside the handle.

If you look very carefully at the image on the left you will note a small black item with a wire leading to a green sleeve. This is the piezo electric crystal and covering...this is the bit we want. No need to cut anything it just pulls away. Depending on the make that you get you will also find that this is attached to a plastic tube and a brass fitting at the top where the spark is created...keep that.

Take your Bic biro and cut off both ends, I used a hacksaw as i find that if you use a modelling knife it can crack very easily.If you are lucky (as I was) you will find the biro casing will slip perfectly over the metal fitting in the main body of the piezo casing .

Making the spark

Take the map pin and with can and not too much pressure begin to drill carefully into the casing. This will need a bit of experimentation but I found that a gap between the pin point and the Piezo-electric metal cap to be about 3 or 4 mm. It is best to do it more and then shave off the pen barrel a bit at a time and test the spark.

Once through the body I placed the plastic tube and a brass fitting mentioned above over the pin and re-inserted it. If you want you can glue in place with super-glue but be aware it does not always stick to all types of plastic so test before hand.

Making it all go bang

This took a bit of trial and error as i found that if the main wire was too close to the casing there was an actual arc across and i had a couple of shocks...not nasty but enough fo make me jump in surprise:-)

After fiddling and a guaranteed spark, it is time to fill it with butane. You hardly need any, just a very small squirt and leave it for about 30 -45 seconds and then press the switch. Now this is not the most efficient of Kitchen Table Science weapons as there is hardly any butane but I have made it POP about 10 times and got the end of a cotton bud to pop out twice.

Just play with it, be sensible with it and don't point it towards your face anybody else or any animals, most of all be safe....YOU HAVE BEEN WARNED

Magic Forest

Piezoelectric Butane Bazooka Biro (BBB)