For the first five years of Make:, we ran a column in the magazine called “MakeShift,” written by Lee David Zlotoff, creator of the iconic TV show MacGyver. As with the show, where science and engineering improvisation were a central theme, each installment of “MakeShift” presented a sticky situation and then challenged our readers to submit “makeshift” solutions. Challenges included such conundrums as dealing with a viral outbreak on a plane, surviving a zombie attack, what to do with a time bomb discovered in an underground parking garage, and how to communicate with the outside world during a high school lockdown. Lee, Make: staffer Bill Lidwell (who edited the challenges), and all of us at the magazine were constantly blown away by the cleverness and intelligence of the responses. People really got into it.
In looking over these columns, we decided that we wanted to bring them back to share with the current Make: readership. In the columns and summary articles, Lee and Bill talked about a MacGyver-worthy measure of intelligence that they called MQ (for “MakeShift Quotient”). MQ is one’s ability to use knowledge of science and engineering, combined with some chewing gum and bailing wire, to fashion workable solutions to problems on the fly. We hope these “MakeShift” columns will go a long way toward increasing your MQ.
Starting today, we’ll be re-running the “MakeShift” columns every Wednesday. The scenario/challenges and the submitted solutions and winners are here all presented together. But don’t hesitate to challenge yourself. Read the scenario, challenge, and supply list first. Spend some time thinking through possible solutions before you move on to the analysis and commentary sections. As was done in the original postings, we have included the full texts of the submitted solutions (linked at the bottom of this page) so that you can go as deep as you want. There’s a lot of information in these articles. If you just want to skip to the winning solutions, scroll down to the Summary section. -Gareth Branwyn
To start things off, here’s the column from Make: Volume 01:
Dead Car Battery
After a relaxing night of camping in the deep woods, you return to your car to find that it will not start. The battery is dead. “Someone” left the parking lights on overnight. You are 50 miles from the nearest road and have limited food and water. You try to call for help, but your cellphone is out of power and out of range. Snowy weather is scheduled to set in by late evening. The situation is serious.
Create a makeshift solution to recharge the battery and start the car. Tools and materials at your disposal include the objects on the supply list below (as well as the car and its components). You have 10 hours. By the way, the car has an automatic transmission–push-starting won’t work.
(2) Sleeping bags
Sterno (stove and fuel)
First-aid kit (Aspirin, adhesive bandages, hydrogen peroxide)
(6) Pack of cola
(1) Dozen limes
(1) Large bag of potato chips
(2) Liters of bottled water
(1) Cellular phone
(2) Road flares
A variety of tools (screwdrivers, wrenches, pliers, Swiss Army knife
MakeShift 01: Analysis, Commentary, and Winners
by William Lidwell
May 13, 2005
The first MakeShift gauntlet was thrown down to take the measure of Make: readers–an intractable conundrum to separate the intellectual and creative wheat from the chaff: a dead car battery in the middle of nowhere; an eight-hour time limit before deadly weather sets in; nothing but your wits, camping gear, and left-over snacks to solve the problem. The result?
Make: readers answered the challenge with audacity and vigor. Solutions ranging from rocket-propelled flywheels to potato chip-and-penny voltaic piles were submitted. What follows is an analysis of the “dead car battery” problem peppered by ideas and commentary from the most lucid of reader contributions. In the end, however, there can be only two winners per issue — readers who submitted the most creative and plausible solutions. These MakeShift Masters and their problem-solving booty are announced at the bottom of this page. Since there were so many excellent submissions, I have also taken the liberty of declaring some honorable mentions, too. No booty for you, but some formal acknowledgement for your exceptional work. Winning entries and honorable mentions are presented in their entirety (links below) for the edification of all.
For those of you who undertook the MakeShift challenge without success, fret not. Unlike the various forms of IQs, EQs, and GQs that are said to be all but unalterable, the very special brand of genius that I hereby brand MQ (for MakeShift Quotient) is unquestionably advanced through the study of science and engineering and through exercises of creativity and problem solving. You can begin developing your MQ by studying the analysis that follows. Explore and evaluate the highly varied and innovative ideas submitted by fellow Make: readers. Read through this, and think about it, and you will soon be thinking like a MakeShift Master.
There are two basic approaches to this challenge: (1) solve the problem in a way that has nothing to do with the obvious parameters of the problem, and (2) start the vehicle by recharging the battery.
A number of readers opted for the non-obvious approach. For example, a contributor on the Make: site suggested the following:
…review your supplies, take what’s needed and get out of there fast, before the snow, a 50-mile walk should take about 4 hours.
No dice. As I replied in the comment, a fast walker can average 3 mph–carrying supplies over rough terrain, maybe 2 mph. Short of being professional athletes, a fit, average couple would be lucky to make it halfway before nightfall (and that’s assuming they don’t get lost or injured along the way). With bad weather setting in, the decision to hike it out could be their last. People die trying to hike their way out of trouble all the time. A far better plan would be to build a fire and wait for help… or, figure out a way to restart the vehicle.
The survival considerations/tradeoffs of how supplies are used (and possibly wasted) were raised by a number of readers. For example, C. Holdredge offered the following admonishment in this regard (I should note that he then went on to provide a very strong solution to the problem!):
In the scenario presented, spending time trying to start the car is REAL DUMB. The subject has two kinds of shelter, a handy forest for fuel, half a dozen ways to start a fire, and will shortly have a source for extensive fresh water. Anyone qualified to be in the woods at all should be able to survive for weeks under these circumstances, awaiting rescue. In the real world, the subject would be much wiser to spend the time stockpiling dry wood, starting a fire, pitching a tent, seeing to their visibility from the air, etc. Fuss with the car to avoid boredom while waiting for the rangers or CAP to find you and haul out.
The general concern is valid. If efforts to restart the car consume precious food and water resources and then fail, you could be in trouble. That said, a large supply of frozen water will be falling from the sky in a few hours. Food is a consideration, but you have plenty and can survive for weeks on light rations. So, while economy of resources should factor in the equation, spending days/weeks in the forest unnecessarily is riskier than not applying yourself and your resources to getting the car restarted–especially if you have the wits and wherewithal to do so.
Last but not least in the non-obvious category are submissions proposing the possibility of push-starting the vehicle. P. Stewart wrote:
You guys stated that “By the way, the car has an automatic transmission–push-starting won’t work.” This isn’t necessarily true. Virtually ALL automatics from the 1930s through the 70s had two oil pumps and could be push started. All that is required for a push start on these older models is a little speed to build up oil pressure. Mercedes-Benz automatics used to have a secondary oil pump driven by the output shaft. I believe they even advertised with this fact into the 70s–you could push start the vehicle when you had a flat battery while this was not possible with most vehicles. Nowadays, with the single pump on the input shaft, there’s no pressure to work the clutches unless the engine’s turning.
The fact that push starting may well be an option for older vehicles with automatic transmissions is a good MQ point to know. Thanks to Stewart and others for raising it. Unfortunately, the challenge as it appeared on the website did not include the picture of the late-model Volvo SUV that was in the mook, which cannot be push started. What can I say–subscribers have an edge!
So, assuming it is not reasonable to hike your way out or push-start the vehicle, and assuming you are comfortable doing something more than collecting wood and waiting for the rangers, let’s look at approach #2: starting the vehicle by recharging the battery. Before we begin reviewing reader responses using this approach, it will be useful to briefly review how batteries work. (NOTE: The electrochemistry of lead-acid batteries is complex. What follows is a simplified “need to know” overview for this challenge.)
A battery is created when two different metals or carbon rods (called electrodes) are placed in an electrically conductive medium (called an electrolyte). Stick a penny (copper-plated zinc) and a nickel (nickel/copper alloy) into a lemon, and you have a battery. Put a copper wire and aluminum wire into a jar of urine, and you have a battery. You get the idea.
Different metals react at different rates (i.e., create charged particles) with the electrolyte. This means one electrode will give up electrons at a faster rate than the other, creating an imbalance of the charge distribution in the electrolyte. Bits of charged electrolyte move from one electrode to the other (direction is positive to negative) to eliminate this imbalance. When these charged bits make contact with the negative electrode, they give up their electrons, and electricity is created. As this occurs, the lead electrodes become more chemically alike, the electrolyte becomes less active, and the voltage drops until the battery can no longer deliver the necessary voltage. Stimulating the electrolyte through some form of additive adds chemical energy to the system and may provide a brief energy boost to the battery. Feeding an electrical current back into the battery restores the chemical difference between the electrodes and recharges the battery (this doesn’t work for all batteries, but it works for car batteries).
So, recharging the battery involves either finding a way to stimulate the electrolyte, or finding a way to feed electricity back into the battery. Readers had interesting ideas on both counts.
J. Russell proposed using the cola to stimulate the electrolyte:
Pour some cola into the battery. Start the car after a few minutes. Of course, you’ll have to replace the battery because you’ve destroyed it, but at least you’ll be alive.
G. Fetters proposed a different means of electrolytic stimulation:
Take the battery out.
Remove the fluid from the battery.
Squeeze the dozen limes into the battery.
Drink the soda and urinate into the battery.
Fill the remainder of the battery with the water.
Wait 9 hours and put the battery back in.
Other proposed additives included saliva, potato chip brine, and hydrogen peroxide. Three disadvantages of this basic approach: (1) though the theory is sound, it generally won’t work in practice for a variety of reasons (e.g., getting the proportions right), (2) if you try it and it doesn’t work, you have likely ruined your battery and eliminated any other opportunity of getting the vehicle started, and (3) several proposed additives run a real risk of blowing up the battery. There is, however, one additive that avoids these disadvantages, as A. Seubert testified:
…Put two tablets [of aspirin] in each battery cell and wait no more than 1 hour (the acetylsalicylic acid combines with the sulfuric acid to get off one more charge.) You can pry the cell covers off with a screwdriver even on most maintenance-free batteries… Then the car will start right up (based on actual experience).
D. Hottle corroborated the soundness of the approach stating:
I know this solution works because I have done it before. To this day, I carry aspirin in my car for just that reason.
As bizarre as this sounds, aspirin will often work depending on the degree of discharge of the battery. It is a reasonably safe approach and usually good for one more engine turn. Be warned that adding aspirin will shorten the battery life, as the aspirin will react with the sulfuric acid to form acetic acid. Good for a boost, but bad for the innards of the battery. Assuming you add no more than a couple of aspirins per cell, it shouldn’t cause significant damage nor preclude additional efforts if it fails to work. So there is at least one safe, viable way to have a reasonable shot at getting the vehicle restarted by stimulating the electrolyte. J. O’Brien took this approach further, however, factoring in some key details that could be the difference between success and failure:
Pour the cola on the battery terminals and connectors and wipe any corrosion off using bandages from the first aid kit. Cola is good at removing corrosion and cleaning the contacts will help get more current out of the battery. Reconnect the battery.
Next, crush several aspirin from the first aid kit, put the powder in the battery, and add bottled water to the battery to fill it to the proper level. The acetylsalicylic acid from the aspirin will combine with the battery acid and increase the charge in the battery, and the water will help restore the electrolyte in the battery.
Since it’s cold out, the last thing we want to do is get the battery and engine warm and certainly not let it get any cooler. Using the sterno stove, heat water in the empty cola cans and pour warmed water over the battery and engine.
Cola has yielded mixed results removing corrosion from battery terminals, but it is certainly better than nothing. Ensuring clean contacts will maximize energy transfer in the circuit. Topping off the water, if it is low, certainly won’t hurt. Warming the battery and engine is a good move if it is very cold. Cold temperatures dramatically reduce the efficiency of the battery, as much as 50% when the ambient temperature is 32 degrees Fahrenheit. Cold temperatures also thicken engine oil, increasing the current required to crank the engine. Carefully pouring warm water over the battery and engine is among the safest ways of warming things up–certainly safer than warming the battery and engine over a fire.
Enough about stimulating electrolytes. In terms of feeding electrical current back into the battery, two basic approaches were offered: (1) create a new battery to trickle charge the car battery, and (2) develop a means of using the vehicle’s alternator to charge the battery.
A small digression to set up some of the science. A typical car battery is composed of 6 cells (essentially mini-batteries), each creating about 2 volts for a total of 12 volts. These cells use two different kinds of lead (lead dioxide and sponge lead) as electrodes and a sulfuric acid-water solution as the electrolyte. The cells are connected to one another and to two terminals, one positive and one negative. To start a vehicle under normal conditions, a battery needs to be able to discharge around 12 volts at 200 amps.
In case you don’t know, voltage (measured in volts) is the force that pushes electrons from one electrode to the other. Current (measured in amps) is the rate of flow of electrons between the electrodes. By way of analogy, imagine you are at a batting cage. The force the pitching machine uses to pitch the ball is like the force pushing electrons (voltage). The number of balls pitched per unit time is like the number of electrons moving between two points per unit time (current). The force pushing electrons is a function of the different reactivities of the electrodes in the electrolyte. The current is a function of this reactivity and the surface area of the electrodes. Since a lot of current is required to start an engine, the electrodes are made into thin plates to maximize the surface area available to donate and receive electrons. The more surface area, the more current.
One last tidbit. Connect multiple batteries in series (i.e., connect the terminals of one battery to terminals of opposite charge on another) and the voltage adds up as the current remains constant. Connect multiple batteries in parallel (i.e., connect the terminals of one battery to terminals of the same charge on another) and the current adds up as the voltage remains constant.
With this out of the way, let’s look at some of the battery ideas submitted. M. DuPont proposed creating a battery using a potato chip/lime/soda electrolyte and electrodes made of aluminum cans and the copper clips from the jumper cables. Her diagram is as colorful as the procedure proposed to create it:
Swig eight fluid ounces of water. Gotta stay hydrated.
Use the knife to carefully cut the top of water bottle off, so that the top is just wide enough to slide in two soda cans, standing side by side. Make sure you keep as much water in the container as you can.
Eat two potato chips for luck.
Finely crush up the remaining potato chips in their bag, and dump them into the water bottle. Stir with a screwdriver.
Eat the banana. No sense letting your blood sugar dip, if it’s gonna be cold.
Squeeze the juice of a dozen limes into the water bottle.
Drink one can of cola, and pour a second can of cola into the water bottle. Don’t mind if it overflows. Then use the knife (or its file, or a rock) to scrape at least half the paint off the two cans.
Carefully widen the openings on the tops of the two empty soda cans, so that the cans can be firmly clipped together, back to back, with the jumper cable. Clip ’em together with the BLACK jumper cable.
Bite an apple. Mmm. Chew and swallow.
Go into the car and turn off or unplug every accessory: radio, fan, heater, headlights (duh), interior lights, and anything plugged in to charge (cell phone, for example). Also, turn the ignition to OFF and pocket the keys. This is so nothing sucks up the power when you try to start ‘er later.
Disconnect the car battery terminals from the car’s cabling.
Using the knife (or file, or rock), scrape any gunk/corrosion off the car battery terminals. Do NOT touch any part of the car while doing this, and, stand on two folded-over, DRY sleeping bags to further insulate yourself from accidentally grounding out the car battery and jolting yourself. Just because it can’t start your car DOES NOT MEAN it can’t stop your heart. Be careful.
Clip the free end of the black jumper cable to the positive (“in”) terminal of the car battery.
Clip the nearest end of the red jumper cable to the negative (“out”) terminal of the car battery.
Dip the other end of the red jumper cable into the water bottle. Position it so that it is dipped into the bottle, fully submerged, but not going very far below the surface of the water. You can notch the water bottle to accept the cable, if that helps keep it hanging in place.
The idea of creating a battery like this to recharge the car battery is sound enough (and if this battery didn’t work, you could always drink the electrolyte!). The question is whether a makeshift battery can generate sufficient voltage and current to trickle charge the car battery in eight hours? Voltage–no doubt. Current–questionable. S. Cahill addressed the current issue in his wet cell solution:
The  wet cells themselves will not deliver enough instantaneous current to start the car, so they must be used to recharge the car battery over several hours. The car battery can then be used to deliver the “cold cranking” amps to start the car (hopefully) for a few seconds. We must develop enough potential to “reduce” lead sulfate back into lead and lead peroxide, which is the reaction that powers the car battery. The six cells of the lead-acid cell need a total potential in excess of 6*2.12 V, or 12.72 V in order to recharge.
These types of batteries could only generate milliamps of current. However, if they can generate sufficient voltage over a long enough period of time, the battery will recharge. As Cahill notes, it will take about 13 volts to overcome the internal resistance of the battery. So, the viability of this approach really depends on the level of discharge of the battery and the amount of time you have to recharge the battery. If the car battery is not too discharged, the ambient temperature is not too cold, and the makeshift battery is able to generate 13+ volts for 8+ hours–could work! A different battery configuration worth considering–known as a voltaic pile–was proposed by N. Kondrick:
…Get your water and cut a corner off the jug and trim it down so it’s big enough to fit all your copper [from jumper cables], aluminum [from cola cans], and cloth as well as some liquid and still be able to hold some liquid.
Now stack all the copper, aluminum, and cloth together in a copper/cloth/aluminum pattern–make sure there is no bridging of metals across the cloth and no bridging of the cloth.
Use a couple of adhesive bandages to attach one end of each wire to the ends of the stack (red wire to the copper end, black wire to the aluminum end).
Stick the whole stack into your plastic container (the corner from the water jug). You’ll probably want to do it sideways so you can more easily cover it all with liquid.
Squeeze the lemons into your plastic container until the juices cover your whole stack.
In this voltaic pile, each aluminum/cloth/copper layer forms a cell. The proposed voltaic pile is essentially eight cells in series. The copper and aluminum layers are the electrodes, and the juice-soaked cloth is the electrolyte. Since these cells are in a series configuration, their voltage adds up and their current is constant. It is doubtful that a voltaic pile of this length could generate the required voltage, though the pile could be extended using different coins and other materials scavenged from the supplies. Current would be nominal, but you should be able to get a few volts out of it. Hook enough of them together and you have a shot, assuming you have enough time.
Creating batteries to recharge the car battery makes use of chemical energy. Another approach would be to use mechanical energy to recharge the battery. P. Salkie summarized the “eureka moment” and the problem of this approach nicely:
…let’s think of one of the most reliable, efficient, proven, general-purpose converters of chemical energy to electrical energy ever to exist on this planet–the internal combustion engine attached to some sort of generator! And you were even smart enough to bring an internal combustion engine along _with_ you! Total Genius!
Oh yeah. That’s the problem, isn’t it–can’t start the damned thing. So, let’s think of one of the other most reliable, efficient, yadayada converters–you. Yes, you (and the person who’s looking daggers at you) are reliable, efficient converters of organic food compounds to mechanical energy. So, eat that fruit, drink some cola, and let’s get down to work! First, we’ll need to come up with some way of generating electricity from mechanical energy. Fortunately, you packed along a generator system with you on the trip! What? Didn’t see that on the equipment list? Well, it’s there all right–the car is guaranteed to have an alternator. It is conveniently attached to a voltage regulation system (which ensures we don’t overcook the battery or blow up the radio) and it’s even already wired in for us! All we have to do is turn it. A lot. A whole hell of a lot. Just an amazing amount of lot.
As Salkie points out, the alternator is sitting right there waiting to be used. The key problem in using the alternator is figuring out a way to spin it fast enough to generate the energy required to recharge the battery. A little bit about modern alternators: alternators generate electricity by spinning one charged copper coil (called a “rotor” or “field coil”) inside another stationary copper coil (called a “stator”). The electromagnetic field created by the spinning field coil extends to the stator, and pulls electrons around the stator coil–voilá: electricity. Since there are no magnets in an alternator, you need some starting current to generate an initial magnetic field in the field coil. This starting current can come from the car battery or some other external power source. Once the field coil is generating a magnetic field, you then need to spin it at a minimum rate of around 1,000+ RPM or nada–2,000 RPM to recharge at the optimal 14 volts. The total voltage coming out of the alternator is a function of the strength of the magnetic field and the speed of rotation. A variety of solutions were proposed to make this happen. R. Bohn offered one innovative way of addressing this problem:
Make sure the parking lights are turned off.
Eat the banana (will need the energy!)
Remove the alternator from the car using the tools.
Mount the alternator on the bumper.
Replace the small belt wheel on the alternator with the larger belt wheel from the engine.
Connect the spare tire to the larger belt wheel (we’re building a flywheel here).
Connect the alternator to the battery using the jumper cables (POLARITY MATTERS!).
Take a break. Drink a cola with some lime juice…
Start spinning the spare tire. This should turn the alternator and charge the battery.
After several hours check the battery by turning on the headlights. They should shine brightly when the battery is charged. Turn them back off!
Remove the spare tire and return it to the car.
Re-attach the small belt wheel to the alternator. Return the alternator, the large belt wheel and the belt to the engine.
Have another cola and cross your fingers.
Start the car and head for home.
P.S. My wife insists that a proper solution must include the banana.
Using the spare tire as a flywheel is an excellent way of getting the most turns per unit time for the least amount of energy. If you could maintain a spin rate of one revolution per second (i.e., 60 RPM) with a 30″ spare tire, you could roughly generate 1,800 RPMs. Impressive. Unfortunately, the field coil was never charged in this solution, so no electricity would be generated. No comment regarding the banana! J. Gasbarro caught the field coil detail and even made plans for a backup power source:
Apply field current. Connect the free wire from the lamp [extracted from the trunk and connected to the alternator] to the battery. If you’re lucky, the lamp will light, indicating that you have current in the field coil of the alternator. Lead acid batteries will often recover some of their charge after they have been deeply discharged if they are just left to sit for a while. Warming them helps. If the lamp does not light, then you have to go to your backup field current source, which is the depleted cellphone battery. The cellphone is smart enough that it will not discharge the battery below about 3V. So there should be enough charge left to power the alternator field current for a few seconds (see About the Alternator section). Use the adhesive bandages to tape wires onto the cellphone battery as necessary.
Finally, S. Curl proposed a way of getting to the core of the alternator RPM problem that would make MacGyver proud:
Using the provided tools, I remove the car’s alternator and wedge it into the side of the bumper where the shaft can protrude….If the wires won’t reach, I extend them with the jumpers. I then mount the spare onto the alternator with a combination of wire lashes from the jumper cables and a clever adhesive paste of mashed fruit supplemented with adhesive bandages. More of this paste and the bandages are employed to affix the two road flares to the tire. My mate, meanwhile, has been carving the apples to create rocket nozzles which are now crammed onto the flares and lengths of gauze “fuse” attached. By hand, the wheel is spun as quickly as possible, and at that moment of peak velocity, the fuses are lit and the rockets fire. The added boost offers peak generation of energy, which is then applied to starting the car, and away we go!! And that’s why I’m a sculptor and not a mechanic!
Since this entry is such a tough act to follow, I’ll take it as my cue to close. Here are my summary thoughts on the challenge. Aspirin is the simplest solution. If it works, you are out of the jam in 30 minutes, no muss no fuss. If it doesn’t work, then Plan B. I am skeptical about the feasibility of creating a battery to trickle charge the car battery given the time and conditions. Even if you have an uncanny grasp of electrochemistry (which some of you clearly do!), getting the electrolytic proportions right and everything hooked up in a rough environment is no trivial task. A lot can go wrong, and there just isn’t a lot of time to tinker. Therefore, the best Plan B is the alternator. Turn the alternator fast enough and it will recharge the battery. If the car doesn’t start, turn it some more. Relatively simple and reliable. The only risk of this approach is accidentally damaging the alternator or belts in the process–so be careful! General factors to consider for all solutions: effects of temperature on the battery and engine, quality of the connections in the car battery circuit, water levels in the battery, acidic strength of electrolyte, minimum RPMs required to generate V/C from alternator, implementation time required by the approach, ability to test progress and tune your approach, simplicity, ability to back-out or try alternative approaches if you fail, consumption of resources needed for survival, contingency plans, and safety.
I would like to thank everyone who submitted solutions to the MakeShift 01 challenge. There were many excellent submissions, and selecting two winners from the batch was no easy task. For future reference, the level of detail provided in the submissions played a major role in the selection process. So, as your high school teacher used to say, “Show your work!”
Winners receive a one-of-a-kind Make: t-shirt to celebrate and show off your unique brand of genius; and the ultimate MakeShift Master tool–the SWISSMEMORY USB Victorinox 512MB–equally useful for hiking and hacking. With these awards and your frighteningly high MQs, we at Make: expect great things. Go forth and solve the world’s problems!
Without further ado, the winners of the inaugural MakeShift 01 challenge are:
Congratulations to the two inaugural MakeShift Masters and the Honorable Mentions (applause…accolades…bowing). All showed an impressive ability to think creatively, apply both theoretical and practical knowledge, and communicate their solutions in a fun and effective manner. I encourage all readers to study these winning entries; it will improve your respective MQs and prepare you for the next MakeShift challenge. Until then, happy making!