If you like this then check out my jack-o-lantern from last year. http://www.instructables.com/id/the-gruesome-suffocating-jack-o-lantern/
Please check out my other instructables and I also have a diy podcast called mechanicalmashup.tv
Step 1: Materials
Ice bucket -$2
Old vacuum hose Free -$0.67
Dry ice - $1/lb from a welding supply store (20 lbs would keep this running for a while)
pumpkin carving tools - $9 exacto-knife kit (on sale)
- potato peeler
Step 2: Jack-o-lantern
Sorry that when it does not blow vapor it looks a little like a blow up doll for people with a real sick fetish.
I was quite pleased with how it turned out considering I have never sculpted anything in my life before. No comparing to pumpkingutter.com though.
You would be amazed at how much you can cut away without poking through. I think the thinnest spot of my face is still 1/2 an inch thick. One trick I found was to poke a thin exacto blade through the wall until it just sticks through on the inside, then pinch the blade and pull it out to gauge how much wall is left. The blade hole you poked will be invisible.
Step 3: Dry ice delivery
Dry ice will not form water vapor if the water temp is below 50 degrees. So I had to keep dumping out the cold water and adding more hot every 5-7 minutes.
I wanted a sealed unit because I wanted the jack-o-lantern to "blow" the vapor, not just have it dribble out of it's mouth.
It was easy to cut a hole in the lid to fasten the vacuum hose with an exacto knife. ( this would have been harder with a pressure cooker)
I drew a skull on the lid to let my son know not to touch.
All that was left was to cut a hole in the back of the pumpkin the route the hose to the inside of the mouth.
Step 4: Video
notes on dry ice-
Dry ice is just frozen carbon dioxide. The "smoke' you see is just water vapor and is not harmful or toxic.
The only way the carbon dioxide can hurt you is if you displace the oxygen in a small enclosed space.
However, the ice is very cold (-109 F!!!!!) and will actually cause burns to your skin. You could pick up a chunk of dry ice and as long as you bounce it around like a hot potato you will not get burned. UNLESS your hands are wet, in which case it will burn you almost instantly (trust me) Plan on wearing gloves.
If you have to store the dry ice for long. Store it in a large cooler and wrap the cooler in sleeping bags and blankets. Don't think you are going to get more than 24 hours without having a substantial amount of your dry ice literally vanish into thin air.