Updated 4" over/under cannon

SpudBlaster15 · Posted: 11/19/2006 1:45 AM Post subject:

I decided to add a fan to my over/under combustion (who wouldnt miss self ventilation and proper mixing of the fuel and air?), and revamp the handle to be easier to hold. I also wanted to try dual spark gaps. Here is the result.

Dont see a battery, wiring, or fan switch, do you? That is because everything aside from the screws that act as mounts and electrodes for the fan (I like having immediate access to all wire to screw connections, and the screw heads themselves) is mounted inside the barrel support. The support can be split in half with the removal of a single hose clamp, making it very easy to access the battery, switch, or wiring for maintenance.

I ran into a little mishap when I was trying to remove the screws holding the fan in place in order to replace them (the heads were severely rounded). The cheap, zinc plated screws snapped off, leaving a stub threaded into my chamber. After much cursing, I drilled them out. However, if you have ever tried drilling a steel screw (regradless of how soft) out of plastic, you would have realized that it is no easy task. I ended up making the hole so large, that I was forced to thread a 1/4" screw into it. It had previously held a 1/8" screw. No worries, and these puppies wont be snapping off any time soon.

I really like the wire covers that I made for my smaller cannon, so I decided to make some for this one aswell. They do a good job of keeping with the "exposed screw, concealed wire" idea. The handle is made using 1.5" pipe and fittings, and is in the most comfortable postion for firing I have tried.

I havent fired it using this configuration yet, but I am expecting everything to work nicely.

BTW, please dont tell me to paint it.