MakeShift 05: Cameron Stoker’s Most Creative Winning Entry
by William Lidwell
July 07, 2006
Cameron sure does some quality thinking on his morning drives. I have also observed that blacksmiths (Cameron is a blacksmith) sure do well on these challenges. Interesting. Woody comments: “Mr. Stoker clearly understood that one of the biggest challenges with this problem is presented by the pressure in the vault, and he offered a number of approaches. He certainly got my attention with his extinguisher hijinks—-assuming he doesn’t accidentally fill the vault with fire extinguisher discharge, he might actually survive this thing.” Congratulations Cameron!
Hi. I was inspired by your makeshift challenge in this issue to do some serious thinking on my morning drive. And writing up the ideas provides a great procrastination outlet the day before tax filings are due.
So, locked into the vault for 48 hours, here’s what I’d try:
There is a little research to be done first. You either need to get more fresh air in, or you need to get the used air out. Towards the first aim, I’d try threading the garden hose out of the 3/4″ vent hole. You guys didn’t specify the hose size; if it’s 1/2″ it may fit through, after cutting off the threaded end. Slipping the steel cable inside the hose and wiring it to the tip can enhance its rigidity to allow threading through tighter bends, etc. You can stand on the table to get closer to the ceiling.
If the hose won’t fit through the vent opening, then I’d just try to jam it into the opening and get a good seal. Then try to breathe through the hose. A person with average lungs has a tidal breath volume of about 0.5L and an additional inspiration volume of 2.5L above that. This should allow breathing through up to about a 6 meter long section of 3/4″ pipe/hose. By taking breaths from inside the room and only exhaling through the hose (kink it to close the hose when you take a new breath), you should be expelling most of the CO2 (and slowly lowering the room pressure). I’d hope any good vault design was sealed watertight to prevent floods from damaging the documents/$$ inside. After several minutes of breathing out through the hose, open the hose and let the pressure differential flush new air in. This should greatly reduce the CO2 buildup in the vault and allow you to make the 48 hour time window.
If, for some reason this breathing method doesn’t work, there are more serious MacGyver tricks to pull out.
You could probably generate a few minutes of supplemental oxygen using the cooler bottle, the water, rags, electrical tape, chalk dust, and the emergency lights. Cut a section of hose about 4 feet long and try to cut two pieces from the steel cable (fatigue fracture it with repleted bending if the pliers can’t cut it at the hinge). Disassemble the emergency lights, all except one to keep some light for you. Thread the pieces of cable one into each end of the hose. Fill a couple dozen paper cups with water first, so you won’t be too thirsty later. You won’t want to drink from the cooler bottle after dumping the chalk powder into it. Slip one end of the hose and one cable into the neck of the water cooler (there may be a way to do this keeping the bottle in the stand, or you may need to take the bottle out, stand it upright, and pack a seal around the hose with the rags).
Connect up the cables to the batteries from the e-lights, and possibly, if you’ve spent too long fiddling around with all this makeshifting, also connect to the rectifiers in whichever e-lights reach. You want the cable in the cooler bottle to go to the negative terminals to get it making O2 in your bottle. If the average e-light has about 30 ah batteries and you’re using three of them, you should end up with about 1.5 gallons of O2 in the bottle, mixed with whatever fraction was air when you started. This reaction will probably take a couple hours, depending on the strength of the solution. If it’s really going slowly, I’d try to dump the battery electrolyte into the cooler bottle to get more activity.
While waiting for your reserve O2 bottle to fill, you should get busy fashioning a sheet metal nozzle from the toolbox metal with the pliers and a lot of slow fatigue-bend cutting. You want a cone with about a 1/16″ hole at the tip and a larger diameter sized a little larger than the fire extinguisher discharge hose i.d. You’ll then stuff the nozzle into the extinguisher discharge hose (probably have to cut off the stock nozzle first).
Also, push the table into position under the vent hole. Hopefully, after about 23 or so hours, you should be done with all this and have a mostly full 5 gallon bottle of air with much higher than atmospheric O2 concentration. You’ll empty out the electrolyte from the bottle (and probably want to seal in a clean piece of garden hose). Get the bottle, the fire extinguisher, and yourself on the table close to the vent (I’m assuming it’s in the ceiling or high on a wall). Practice the steps in your head a few times, because if things screw up, you’ll drown in a vault of CO2!!
Here’s what’s going to happen:
You have the O2 bottle w/ hose kinked and stuck in your mouth. You have the cone nozzle secured in the end of the rubber fire extinguisher hose with the pliers acting as a hose clamp, and the handles of the pliers are taped or wired together so you don’t drop them. You’ll position the nozzle about 1/2″ from the opening of the vent tube centered on it and axially in alignment. Hyperventilate a little to get your own O2 saturation as high as possible, maybe even take a puff from the bottle if the vault air is getting really stale by now. Hold your breath!
Pray a little, and then open the fire extinguisher valve all the way, and keep the nozzle aimed perfectly out the vent pipe. Hopefully the CO2 extinguisher discharge jet will be fast enough and collimated enough to create a vacuum in the vent pipe and suck a lot of the stale vault air out with it. You’ll know if it’s working by feeling the pressure change in your ears. I’d guess the extinguisher could run like this for up to ten minutes, during which time you have to carefully breathe from the cooler bottle of O2-rich air. Don’t breathe too deeply because the bottle air is probably really nasty-tasting, especially if you made the ‘improved’ electrolyte. Also, be very careful that you don’t pass out. You may have to stop well before the extinguisher is emptied if you’re getting faint.
When the extinguisher jet is starting to wane, quickly shut it off and jam the ball of you palm over the vent hole to seal it. Keep pressing hard for as long as you can stay conscious to give the CO2-rich air time to dissipate away from the other end of the vent pipe.
If all goes well, you’ll pull you hand off the pipe just before passing out and be greeted by a rush of fresh outside air coming in the vent to equalize the vault pressure. If the fit of you Macgyvering was precise enough, there will be enough fresh air to tough out the remaining 24 hour period until the door unlocks. If not, then not. Alas.
That’s my little scheme. You might be able to do it more simply, but you run the risk of boredom with nothing to fret over.
Thanks for your consideration.