This weekend I was carving pumpkins with my girlfriend. Pumpkin carving, a soothing time to bond, relax, and justify having power tools. Rather than hacking away at a pumpkin with a dinner blade, my trusty jigsaw and dremel did most of the cuts and an exacto knife detailed. It was much less effort and the pumpkins came out great.
Being me, I wasn’t settled with a mildly dangerous tea candle. I upgraded the wick by adding part of a regular candle. This made the pumpkin burn with a much more ominous glow (Harzard +1).
It was good, but not great. I went down to the shop and bore a hole into the back of the pumpkin. Add one spray can and that brought the pumpkin from seasonal fire hazard to double fisted spray can/fire extiguisher dangerous (Harzard +3 Safety +2).
In hind sight I should have bore the hole larger. Why? Well the fuel I’m spraying there tended to puddle up in the opening and set the pumpkin on fire, thankfully the pumpkin was fresh and still moist.
No it’s not a stargate, believe it or not it’s a bladeless fan. This fan blows a stream out of the blue ring. The blue ring has a special airfoil shape that can magnify the airflow up to 15x. Since it involves no blades this stream is uninterrupted. This fan seems pretty cool (if $300 means nothing to you,) if you ask me I’ll stick to my propellor style fan. Mine comes with soothing fan noises and doubles as a sound effect generator.
It certainly has the wow factor, but hackaday.com pointed out it probably has blades in the bottom to push air into the ring. Perhaps not the same traditional style but blades still. This design is very novel, so as far as the user is concerned it’s bladeless. It’s like buying a Roomba and realizing it needs to be emptied every once and a while.
Dyson also developed the Airblade hand dryer (the funny looking one you place your hand into and pull out slowly.) Plenty of videos on their site.
It’s really easy to make. All you need is a handful of items.
Label: Get the label from this site: http://www.weeklygeekshow.com/2009/07/fallout_cosplay_accoutrements.php Scroll down a little until you reach the template for buffout (it’s going to be a link to a jpg file). Once you download it you’re going to have to print it out to scale. It should come out exactly 6 inches long and 2.5 inches tall. An easy way to do this is to toss the picture into microsoft word, where it should automatically get scaled to the correct size.
Bottle: Next you need the bottle. I got mine from here, http://www.containerandpackaging.com/item.asp?item=B633 The bottle costs 70 cents but the site charges a surcharge of $10 if your order is under $50. To get around the surcharge I requested the bottle as a free sample. The store allows you to order a single free sample of any product. The only downside is that you still have to pay the $7 shipping cost. Don’t forget to get a matching lid for the bottle: http://www.containerandpackaging.com/item.asp?item=L207PS
Now you wait. The bottle and lid should arrive at your door steps in 3 to 5 business days. This is a good opportunity to go out and buy a pack of Altoids. You’ll need them for later.
Once you have the bottle all that’s left to do is stick the label on. I printed my label on regular paper and used permanent double sided scotch tape to adhere it to the bottle. A strip of tape at the start and end of the label will hold it on forever.
After you get the label on, fill the bottle with Altoids and screw the lid on, tightly. The lid you purchased has an inner liner that is going to fuse with the rim, and seal the bottle air tight; giving your Buffout that straight-from-the-factory look. Like this:
Brand new, factory sealed Buffout
Opened bottle of Buffout
Enjoy! These upgraded Altoids should now give you an instant +60HP, +3END and +2STR !*
* Note: Altoids might not actually give real life character bonuses, other than fresh breath.
Matthew Shieh created this very interesting audio meter. Instead of the typical LM3915 VU meter, Matt designed the amplifier to capture ambient sound from a small mic. For the interface he used a photoresistor and capacitive touch button controlled by a PIC16F716 . The photoresistor lets him dim the LEDs when it’s dark to save power. His project really shines in the write up and best of all fits into a petridish.
Chris linked me to this video, it’s a vortex cannon on steroids. When a spherical mass of a fast moving fluid moves through the air, it can form torroid shaped vortex rings, similar to blowing smoke rings. This helps the mass stay together as it moves through the air so its almost like an invisible ball of air.
Lionel Oliver has an amazing site documenting his experiments metaling and casting metal. He shows how to build a variety of furnances from a simple charcoal furnance out of bricks and dirt to more complex propane furnaces. The best part is he does this all in his backyard.
Once you can melt metal you can start recycling old things like aluminum cans or lawn chairs and forming real tools and parts.
Ilya, (one of the other editors) informed me the other day of how he found my Spanish clone. Turns out somewhere in Canada there is an electrical engineer named Carlos who hosts a pretty cool project blog Carlitoscontraptions.com. A lot of his hardware projects match ones I’ve done in the past.
I’m particularly a fan of his Iron Man repulsor gauntlet. It allows a lot of freedom in motion and it lights up as he bends his wrist. He has really good pictures and a video of it here.
I have my own side project replicating the Iron Man Wrist Rocket. Its on/off because I’m using CO2 cartridges to fuel it and I’ve shot them all. Perhaps if I ask nicely, Carlos will want to collaborate. We can use his for the left arm and mine for the right… now all we need is an arc reactor…
Air Cannons are amazingly fun to play with at BBQs. Its really just my adult Nerf gun. You just fill the pressure chamber with a compressor and then hit the valve and watch the thing go. My normal projectiles are confetti, fruits, stale dinner rolls and glow sticks. I usually fire a couple shots of water to clean the cannon. The water shots make a really cool rain effect and feels great in the summer.
What about Explosive Cannons?
I used to build spud cannons powered by hairspray and starter fluid when I was in boy scouts. They are definitely more portable because you don’t need an air compressor and it’s a faster reload than a bicycle pump. They are half the cost too.
I finally got sick of the inconsistencies and went air powered. With gas powered some would never fire, some would fall short, some would even ignite the PVC on fire. Air powered gave me a measurable force and the extra cost was well worth it.
This video is NOT MINE! It does display the reason why I don’t like Combustion Cannons
Is it Safe?
If you know what you are doing Air Cannons made from PVC pipes are generally unsafe. If you don’t know what you are doing, then well, adios, nice knowing ya. PVC by any respected engineer is not a good pressure vessel, it’s easily damaged when dropped, brittle in the winter, and if it does not fail, it becomes a pipe bomb with PVC shards with you right next to it. Schedule 40 pipe can be rated around 200+psi. As a safety margin I usually pressurize my cannons around 75 psi. I used a tire valve stem to pump air in and it tends to leak at higher pressures so I don’t wish to break it. At 75 psi my cannon turns a solid apple projectile into pure sauce.
My Portable Party Cannon
I made a smaller version of the big one for parties. It’s the same cost as the big one ~$36, but the benefit is that it can be powered by a bicycle pump rather than a full compressor. I also added a solenoid sprinkler so I can add a remote in the future. Below are some photos.
This one is the miniaturized version, instead of using a 1″ manual valve. I used a sprinkler valve from Home Depot. I am hoping to one day build some electronics for this and make it remote. I built it in an hour for parties to launch confetti.
That black electrical tape is to hold three sections of pvc around the cannon as a tripod. Air goes in from a bicycle pump from the tire valve stem on the right. It takes about 20 pumps to hit 35psi for confetti.
Streamers are usually inexpensive ($1 a roll) and they are fire retartant. It takes 1/3 of a roll to fill the barrel. I cut the streamers into 1″ x 0.5″ sections of confetti and cram them down the barrel. If you make it too small it becomes a mess to clean up.
The barrel on my design screws off so I can load multiple barrels and the change the size.
This manual bypass on the solenoid valve works well enough till I rig up a remote system.
How to Build One
There are some really complex designs out there, but if all you want is a big BOOM!, smirk and “Holy Crap that’s Awesome!” I recommend a compressed Air Cannon with a simple 1″ valve.
(SpudFiles) has plenty of research and forums on the topics, so there is no need for me to reinvent the wheel. Spudtech.com also sells a lot of the parts you wont find in Home Depot, like clear PVC and 125psi safety valves.
Other People’s Videos
I’m crazy about not having accidents with my cannon, but I can’t say the rest of the internet is. Here are some fun videos of people without the same philosophy.