One day, my friend Jeremy and I were bored (as usual). So, we decided to try to make a pneumatic air cannon, much like the ones described on xinventions.com. Thus, soon after, we made a small paintball gun sized cannon. This first generation cannon probably shot a paintball about 200 feet if we were lucky. It had a 12"x2" PVC tank that was controlled by an inline solenoid sprinkler valve. We used a compressor to fill it up to 150psi. This amount of pressure combined with how much volume in this short tank were the main factors controlling exit velocity. Both Jeremy and I were only slightly happy with this model, so it was back to the drawing board for us. We tried to figure out what the best combination of volume and pressure would be. But, we are both slackers so we just figured more is better. Generation II of our cannon used a tank that was approximately 8 times the size. This cannon is much better to say the least. We calculate an exit velocity of about 800 fps. Remember we're shooting paintballs. We did a range test, and the shots went out of sight. We also tried to shoot some of my lawn furniture, and the paintballs shot straight through them. That was the end of our air cannon testing. Oh well. Generation III sometime in the future perhaps...

I had heard about people making combustion cannons that shot potatoes over 100 yards using only hair spray as propellant. CJ and I decided to make one of these, but we weren't satisfied with a short one, so ours has a 6 foot long barrel and a 3-1/2 foot combustion chamber. It shoots potatoes about 200 yards straight up and about 400 yards if we go for maximum distance, not bad for a first try. When we shoot it, flames come out the end of the barrel. Fire. Heh.

Barry's Coilgun Design Site
Railgun.org
Linear Induction Engines

CJ and I drew up plans for an air cannon with 25,000% more volume than the last one, it also incorporates the use of 4 2" solenoid valves, each of which is $65, so I don't think we'll be able to make it anytime soon. It uses over 60' of 4" PVC pipe and has a 10' barrel. $$$$$. If anyone wants to front the money, feel free to let me know. It should be able to launch a potato into the next state, if it didn't explode first that is.

When my parents decided they wanted to buy another car, they decided they'd give me the old vehicle. They orginally bought it as a family car, and now that my sister and I are leaving they decided they wanted small cars instead. Thus, we now have two Honda Accords and the old Vanagon. Now, the Vanagon has a stock 82hp water-cooled engine, and it is a full size van. Anything seem wrong about that? The answer is yes, it is very underpowered, not to mention it is becoming hard to get it to pass the required smog checks here in California. So, I am devising plans to upgrade it with a 200hp GM Vortec V6 4600 engine. I figure it will have enough power then. Anyway, it will cost around $5000 by my figuring, and I have nowhere near that to spend right now, so I will have to wait.

Upgrade List
• Cup Holders :)
• Power Windows
• Power Locks
• Alarm System
• Paint (Black)
• New Air Conditioning/Heater
• Replace Side Mirrors
• GM Vortec 4600 V6 Engine
• Captain's Chairs
• New Sound System
• Replace Dash with Computer
• Lazy Boy Chairs to replace Back Seat
• Twin Bed in rear
• Refrigerator
• Add Auxillary Battery

Here are some sites with some more technical details:
Vortec V6 Camper
Vanagon Engine Swaps