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emergency vehicle escape keychainby mikeasaurus on July 14, 2009

Table of Contents

intro: emergency vehicle escape keychain ..........................................................................................

step 1: .....................................................................................................................

step 2: snap your blade ........................................................................................................

step 3: cut card to shape .......................................................................................................

step 4: add in an LED .........................................................................................................

step 5: light sanding ...........................................................................................................

step 6: glue .................................................................................................................

step 7: drill keychain hole .......................................................................................................

step 8: smash that spark plug ....................................................................................................step 9: science, limitations, and further reading ......................................................................................

step 10: action! ..............................................................................................................

Video ....................................................................................................................

step 11: final thoughts .........................................................................................................

Related Instructables ...........................................................................................................

Advertisements ...............................................................................................................

Comments ...................................................................................................................

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intro: emergency vehicle escape keychainCar accidents. Yikes!The best way to avoid being in an accident is to use safe driving techniques and always pay attention to where you are going and to other cars around you. However,despite your best efforts you are not in control of other drivers and sometimes accidents happen. Bummer.There are options available on the market for vehicle escape devices which will help you out in case of an emergency, however a few of the models I have seen aredesigned to be places under your seat or in the glove compartment. What these products do not address is that the location of these devices are often inaccessible afteran accident or are thrown around the vehicle during impact.

This project will outline a design for a post-accident escape device which will never be further than your steering column. In the case of an emergency, use your good judgement to get yourself to safety.Be smart and ensure your vehicle is equipt with safety gear such as tire repair, cones, and road flares. This project is part of a complete breakfast. car survival kit.

The design consists of has a small blade located in a narrow channel designed to cut your seat belt should it become jammed, there is also a shard of ceramic which can be used to break your driver's

side window allowing you to escape your vehicle if the door has become compromised. An LED can also be fitted allowing you some light if it's dark. The entire device has a non-slip grip made from a

waterproof material and can be attached to your car key ring.

This instructable is entered in the Pocket-Sized Contest .Remember to vote for your favourites!

Enough talk, lets make something!

step 1:Materials:

spark plugplastic (credit) card2-part epoxy (or other strong adhesive, must be able to bind metal to plastic)permanent markerhobby knife with 'snapable' blademasking tapesandpaper (I used 3 types: 120 grit for wood, 120 grit waterproof emery cloth, and a stiff hobby board sander)hammervice grips (grips or clamps)drill (with metal bit)

Knives are serious business. Be safe , and use responsibly.Spark plug shards are also serious business, use goggles and gloves .

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Image Notes1. spark plug (ceramic. not porcelain.)2. marker3. hobby knife (with snap-off blade)4. 2-part epoxy5. sandpaper6. gentle persuader7. masking tape8. card with no more credit :(

step 2: snap your bladeGrab your hobby knife and extend out the blade exposing a few sections. I measured off 2 section with a total length of about 1cm (1/4"), depending on the desired sizeof your cutter and the type of knife you use yours may look different. The size of the cutting blade will dictate how large your device will be.

Once the blade is extended to the desired length lock the blade in place (seriously, lock that bad-boy down). Place a small piece of masking tape over the exposed bladeand press down on an angle on the exposed portion. I f done correctly the blade should snap along the scribe, the masking tape prevents the snapped blade from flyingout and stabbing you in the face (because we've all been there).

Image Notes1. this is what we're after

2. notice the diagonal scribe marks, this allows the blade to break in predetermined sections.3. locking mechanism, learn how to use it .4. blade safely wrapped in masking tape

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step 3: cut card to shapeNext, use your marker and creative license (you have your license, right?) to design the shape of your belt cutter and channel opening. Since you'll be covering the plasticcard you can draw willy-nilly to find that perfect shape. I chose a minimalist design but you could go for whatever shape and size you wanted.Position the small blade you just snapped over your design to ensure that you have enough room on the card. I recommend maybe going a little larger than you need assanding the plastic is easy, the metal not so much.

Once you are satisfied with your design cut the card into two blanks, mine measure 2cm x 5.3cm (0.8" x 2") each. Use your hobby knife to carefully rough out the innerchannel, this channel is what will guide the seat belt to the blade.

Image Notes1. sketch out your design and roughly position everything.2. cut into blanks.3. carefully cut out inner shape.

step 4: add in an LEDDepending on your size and design you can include an LED to your belt cutter.I had an old bike lock key that had a small LED in the handle, the battery was small and just managed to fit on the cut plastic. Find a good spot and carefully position yourLED and battery.

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step 5: light sandingGive your cut plastic shapes a rough sanding to take off any burrs and sharp corners. It 's easy to get into the t ight spots before it's assembled, but don't go too crazysanding as the final sanding comes after we glue the two halves together.The only place that needs some roughing is the inside faces of the halves being glued, this roughing allows a stronger bond between these two glossy surfaces.

step 6: glueSqueeze out some 2 part epoxy onto some scrap and mix it up. Apply a thin coat of epoxy on one half, gently position the blade and LED assembly, add an extra dab ofglue to the other side of the LED and blade then close the halves.

Next cut a few strips of waterproof sandpaper the rough shape of your plastic card, apply another thin coat of epoxy to the underside of the sandpaper strips and coverthe outside of joined halves.

Clamp. wait. trim excess with hobby knife and sand all edges smooth.By waiting until now to do a more thorough sanding you'll even edges on both sides and have a smooth top and bottom.

A word on epoxy: As with most glue a good rule to follow is "less is more". This means that adding huge gobs of glue does not equate to a better bond. Most epoxy is stronger than the components being glued, using too much will result in a sticky mess with no added strength. Be smart, use enough to adequately cover the area you are working on,when you clamp it together some glue will ooze out but not so much as to glue the clamps to your project.

Image Notes1. mix your 2 part epoxy

Image Notes1. blade sandwiched and centered. apply glue to sandpaper.

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Image Notes1. clamp and wait for epoxy to set. (right amount of epoxy = no excessive oozing)

step 7: drill keychain holeAfter sanding allow the epoxy to completely set (maybe an hour, maybe overnight depending on the type of epoxy used), then you can start drilling the hole to hang yourbelt cutter from your key chain.

You will need to use a dri ll with a bit specifically designed for metal, if you use a wood bit you run the r isk of damage to your tools, this project, and yourself. Slap on yoursafety goggles and slowly start drilling.The reason we're using a metal bit i s because we're going to drill through the metal blade inside. Start small with a pilot hole, then change to a large bit and dril l again toenlarge the opening.

step 8: smash that spark plugWe're now going to break our spark plug to obtain a shard from the ceramic insulator.For safety sake treat ceramic like glass, it splinters and shatters when broken. These slivers can fly everywhere and can embed themselves into your skin if you are not

careful.Wear goggles and gloves!! this is not an option, you are putting your juicy eyeballs in peril.

Put the spark plug inside an old sock to prevent splinters flying when impacted, then take it outside and smack it a couple of times with a hammer, it took me about 3 solidswings to break the ceramic apart. Carefully turn the sock inside out and empty out the broken pieces, select a shard that is small enough to fit on your project.Ceramic shards have sharp sides which can cut fingers, carefully file down the sharp edges of your shard. Sanding down the sharp edges of ceramics using regular woodsandpaper isn't going to work that well, try using emery cloth instead.Once the edges are smoothed out mix up some more epoxy and put a dab on the ceramic shard, then place the shard onto the end of your belt cutter.

edit: Through some post-published field tests it's been determined that a smooth rounded surface does not work as well as an exposed edge. Your edge does not need to beas sharp as a razor, so you can sand off the hard edge so it doesn't cut you. I have also discovered that the shard size can be very small, half the size of your fingernailwould work. Check out the video in step 10.

edit: there's been some discussion in the comments section regarding the composition of spark plug insulators.My research has uncovered that insulators can be (and are) manufactured from both ceramic and porcelain. The insulator tip at the bottom of the plug is almost always

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made from ceramic.Checking the definition of porcelain it says that it i s a type of ceramic, though with a Moh scale rating lower than just ceramic due to the added minerals. This makesporcelain a poor choice for this project, make sure you check before you start smashing.

In any case the idea of this is that we are looking for a ceramic shard to shatter the glass. If you are unsure of the composition of your spark plug insulator you can eitheruse the insulator tip (located at the end of the spark plug) or simply find another source of ceramic. There's a few household ceramics that come to mind, howevercarrying around a shard from your toilet is kinda gross.

Image Notes1. smash, then sand sharp edges.

Image Notes1. for best results use a piece that has an edge. lightly sand so it can't cut you theninstall.

step 9: science, limitations, and further readingSome Science:The Moh scale measures the hardness of a mineral and it's ability to scratch a softer mineral. On the Moh scale diamond is the hardest at 10, ceramics measure around 9, glass is close to 6.5, and talc is

at the bottom with 1. Using this scale we can see that ceramic is harder than glass, which is why a small shard of ceramic can damage glass. If you want to know more about the hardness of minerals why

not read all about the Moh scale .

Through ceramic is much harder than glass there are some limitations

Limitations:Laminated glass :

Laminated glass is glass which has been sandwiched with layers of plastic to allow the windshield to retain it's shape after an impact and prevent it from showering you with shattered glass. You can try to

chip the windscreen and shatter it with the ceramic shard and kick out the glass once shattered, but your better option is just to use the driver's side window as they are not usually laminated.

Thick Glass.

If you have bullet-proofed your minivan windows to avoid suburban assassination, or if you are riding in the Pope-mobile this will not work.

Plastic Windows.

Some custom cars and older vehicles use plastic composite windows, it will not work for these types of windows.

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step 10: action!Not content to let science and other internet videos make my point for me, I went to the auto wreckers and managed to talk my way onto the site.

The owner was skeptical to the reasons why I was there and asked one of his workers to show me a car I could test it on. While walking along the aisles of cars I askedmy escort if he'd heard about ceramics working on breaking windows. Judging by the look he gave me it was like asking a sailor if he'd ever seen water. His exact wordswere "it's the oldest trick in the book.".

To complete the breaking action there needs to be impact , simply applying pressure to the surface of the glass will not work.Check out the video below where I toss a shard at the window, the force used was less than what you'd use to clap your hands together.

Video

step 11: final thoughtsYou now have a small device which, in the event of a complete wreck, is able to cut your belt, smash your window, and light your escape!

Why not make your own and post the results in the comments? Comments that include a picture of your version of this project will earn themselves a digital patch, goodluck!

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d v r t i s m n t s

Comments42 comments Add Comment

thatoneguydavid says: Jul 14, 2009. 6:18 PM REPhave you tested it? I'm curious how you would use the glass breaking portion. It does not seem like there is much to hold on to, how would you hit thewindow with it? do you plan on holding the ceramic side to the window with one hand and use your palm to hit it?

blah12344321 says: Jul 14, 2009. 9:24 PM REPyea i think palm smack would work best with this.

static says: Jul 16, 2009. 10:41 PM REPMost likely the only way it will work. Use the ceramic to scratch the surface of the tempered glass to weaken the surface tension, than give it a goodsmack hoping you see it shatter into thousands of relatively harmless pieces. Assuming the side glass is tempered glass, not laminated

mikeasaurus says: Jul 18, 2009. 4:30 PM REPnegative, there needs to be an impact .Hold like nunchucks and give it a whirl.

ItsTheHobbs says: Jul 15, 2009. 6:20 AM REPThat's what I was thinking too...

JohnMichael says: Jul 16, 2009. 8:36 PM REPTrying to knock out the front windshield will take forever, and I fail to see how this piece of porcelain is going to help. Side windows are made of temperedglass and much easier to get through than the windshield. However, this still takes an amount of force focused on a very small point. That piece of porcelainis not going to do anything to the window. It would make more sense to use the point of a nail setting punch.

mikeasaurus says: Jul 16, 2009. 9:16 PM REPThanks for looking!You should keep reading, step 9 talks about the limitations.Also, this step has also been edited and expands upon the issue of ceramics against glass.

JohnMichael says: Jul 18, 2009. 12:58 PM REPMy point is not about ceramic verses porcelain. That round piece is not going to do anything against tempered auto-glass. If a person cannot kick outthe side window they are certainly not going to get enough focused force to break it with that little round thing. There is a reason the auto emergency

escape hammers come to a point. The general concept is good, unfortunately, I do not think that part of it is going to work

mikeasaurus says: Jul 18, 2009. 4:27 PM REPJohn, thank you for taking the time to address any shortcomings you think you see regarding this project. Please direct your attention to the newlyadded step 10 which has a video of the resultsYour concerns have merit, as a rounded end will not work as well as an exposed edge, though it does still work. The edge does not need to berazor sharp but does require something more than the rounded end I show in this instructable (though with slightly more force the rounded endwould also work).

As discussed somewhere else in these comments, the method of applying pressure will not work, there needs to be a striking action. Holdingyour keys like nunchucks with the ceramic end loose you can achieve this striking motion and easily break the glass.

You make an interesting point when you mention that commercial available hammers use a point to shatter glass. It is important to also includethat these types of hammers have a tip made from hardened steel, not ceramic ( though I've seen those too). The point on metal hammers is tofocus the striking action and overcome the hardness of the glass (steel has a Moh of 6.5, the same as glass), hammers using ceramic tips whichare also pointed are doing so to add that extra dimension and focus the impact further, though as demonstrated is not entirely mandatory.

If you still have reservations about the methods and how well ceramics work against glass and the shapes needed to complete the action then Isuggest you locate an auto wrecker and try it yourself, there really doesn't need to be much pressure to get it to shatter, just a direct impact.Thanks again for your insight!

goldenbacon says: Jul 17, 2009. 4:02 PM REPI just made mine last night, its a pretty awesome rope cutter too.

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mikeasaurus says: Jul 18, 2009. 3:40 PM REPThat's great, I'm glad you tried it!

If you've completed a project based on this instructable and post a picture here in the comments section you'll get yourself a patch!

wakojako says: Jul 16, 2009. 12:24 AM REPuse this it's cheap and iv tested i t the black bit smashes windows all you do is push it against glass.

TR!5T4N says: Jul 18, 2009. 10:09 AM REPwhere can you get it from?

l8nite says: Jul 15, 2009. 1:04 PM REPHave you tested this? Go to a salvage yard and try cutting a couple seat belts and breaking windows. As a former paramedic I can tell you that cutting threwa seatbelt isn't easy even when your calm and unhurried, the best tool for the job is a serrated blade like that on a folding lock knife.

Breaking a window isn't as easy as it seems either, rescue personnel often carry a spring loaded punch for emergency car entry (hammers and the like cansend glass shards all over the interior and patient) The best place to hit the glass is in a lower corner where its firmly supported ( I've seen fire axes bounceoff a car window during training sessions) I question how much pressure you can apply with a shard of ceramic.

All that being said, this was a well done instruc and if nothing else the blade would make a convenient package opener

mrjack says: Jul 17, 2009. 2:54 PM REPYou are very correct sir, breaking glass is pretty darn hard. I have seen people break their hands and lots of other stuff trying to get into cars through thewindow. Now on the other hand my sister, who is a Chicago Police Officer, once told me that she catches gang bangers with little chunks of spark plugall of the time. You can take a tiny shards and lob it at a window to make it shatter. I have seen this in action in a junk yard, very very cool. I believe italso has something to do with hoe sharp the microscopic peaks and valleys are on the ceramic.

mikeasaurus says: Jul 16, 2009. 8:23 PM REPl8nite, thank you for your comment.Cutting through the belt is a combination of the angle of the blade when you assembled your cutter and how much time you have when cutting a belt.If you think that a home made device created from salvaged materials is going to cut faster and cleaner than paramedic grade cutters, then you havemissed the objective of this instructable.

The physics behind ceramic shattering glass is solid. The amount of pressure applied is directly proportional to the person applying it. However, pressureisn't enough to shatter some windows, a str iking motion is needed. In this case you would need to design your device to accommodate your preferredmethod of gripping in order to complete an effective impact against the glass. There is no magic formula for this as it is dependent on the user, which is

why they offer the spring assisted versions you mentioned.The spirit of this instructable is to illustrate what is possible. How it is built, executed and used is in the users hands. If there is any doubt to the buildersabilities or the materials in question then you are better to put your mind at ease and buy a commercially available unit.

Thanks for your considered response. I have updated a few portions of my instructable accordingly.

tdean87 says: Jul 17, 2009. 8:54 AM REPHey, great 'structable, really like the concept, I did however find a two flaws in the design. Both however are simple fixes, one, the color as a first responderwith the local fire dept. in suburban NJ we have highways all over and the access to a seat belt cutter is high, however I think using brighter colored cardwould benefit the user so it's easier to find in a dark car. the other is the placement of the key ring, where it attaches to the cutter, in haste I could see thekeys "flopping" in the way of the blade, thus making the cutter useless, perhaps putting it on the opposite side would prove more effective. other than thatGREAT work!- TMDean332

static says: Jul 16, 2009. 11:58 PM REP

I sure you are tired of reading it, but it would be nice to see video of the tool in action. Initially I though the porcelain was to be used to weaken the temperedglass making it easier for a simple blow by an occupant to shatter the glass, but after reading the comments section, and rereading the 'ible, I see that isn'tthe case. Respectfully I believe you still have it wrong. While it important for the part of the tool striking the glass to be harder than the glass, the most importpart is to design the tool to place the energy to the glass in the smallest area possible, but your design dissipates the energy over a wider area, not what youwant. Let's suppose you are able to ex exert a 100 PSI to the tool, and the tool that makes contact with the glass is 1/64 of an inch in diameter. That 100 psiof force becomes 12500 psi at the point the tool makes contact with the glass. I do like your idea of putting the tool on the key ring, where it's most likelygoing to be available if ever needed. If I where to duplicate your idea I use a sturdier material for the body, and try to find a very small piece of carbide toolmaterial for the striking point. All in all a good 'ible, so I'll click on that 5th star.

little red says: Jul 16, 2009. 4:32 PM REPthis is awesome how do I vote for it?

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mikeasaurus says: Jul 16, 2009. 8:33 PM REPthanks!

Voting Starts: Jul 20, 2009Voting Ends: Jul 26, 2009

you can see all the entries here , and you can vote for more than one!

Esmagamus says: Jul 16, 2009. 7:48 AM REPNote: spark plug insulators are made of porcelain. Vases and the like are made of ceramic, dishes and stuff are made of porcelain. Try breaking both andyou'll see porcelain is a lot harder, less porous and a lot more prone to break in tiny shards.

mikeasaurus says: Jul 16, 2009. 8:29 PM REPYou have caught on to something very interesting. My research says otherwise, though doesn't disclaim your comment.

Check out the revised step 8 , and thanks for the insight.

blah12344321 says: Jul 14, 2009. 9:28 PM REPdid you test the belt cutter, because with all the ones I've seen the blade is mounted on the vertical wall of the slit so it cuts the belt as it slides up. with yourdesign it may just crinkle up and not cut. and it would be awful if something happened to someone and they had to rely on this and it didn't work. you shouldprobably add a disclaimer to this 'ible

mikeasaurus says: Jul 16, 2009. 8:26 PM REPUnfortunately I have no control over the methods and materials other people use to construct their own devices, this guide aims to outline what ispossible to construct using salvaged materials and what the desired results are. Without offering a comprehensive QC/QA process it is impossible to

determine if anyone else's belt cutters would ever work!

nc527 says: Jul 14, 2009. 10:21 PM REPI would think using a piece of g-10 or micarta woud be stronger then a credit card

mikeasaurus says: Jul 16, 2009. 8:21 PM REPAlright mr.smarty-pants, Why don't you make your own using those materials and post your results and show us the next version possible, you can eveninclude any other improvements you can think of! You'll even earn yourself a patch!

HarveyH44 says: Jul 14, 2009. 6:16 PM REPHow long does it take to cut through a seat belt with one of these? I don't usually wear a seat belt, but Florida made it a primary offense on July 1, 2009, andI get a litt le paranoid about not wearing one. Already got a warning, think it was because I was already in my driveway, and out of my vehicle, before thesheriff pulled up. My security camera in the carport, might have been a factor as well. Saved me a $116 ticket... They should have left it a cheap nuisanceticket, where it's more of the wasted time paying it at the courthouse, than a financial burden.

Might build one of these, or similar. Don't like carrying a blade in the glove box, police always label them weapons, until proven otherwise...

droidman says: Jul 16, 2009. 8:52 AM REPin europe if you dont use it either you pay a big fine at the time or you say goodbye to your driving license. (this law exists in almost every europe countryfor more then 25 years now)

ntraft says: Jul 16, 2009. 8:24 AM REPIn at least 90% of cases, if you're not wearing your seat belt, then you won't even be alive when the t ime comes to cut through it. And you won't have achance to try out that ceramic either; you'll already have broken the windshield with your skull. You may want to rethink this strategy.

wupme says: Jul 14, 2009. 9:19 PM REP

There are still people don't wearing seatbelts? Amazing...

But with cutting through the belt. I think it would be better if you made the blade quite longer and at an angle. So it looks like the beltcutting thingies youcan buy, it would definately ease the process and should go faster.

Jack of Most Trades says: Jul 16, 2009. 7:30 AM REPYears ago, we shot a anti-crime spot at the Impound lot where a detective showed us how quickly he could get into a locked car and snatch the stuff on thefront seat, He used a spring-loaded punch and sparkplug bits to take out the side windows. Less than 5 seconds.We spent some time knocking the windows out of a bunch of junkers that were headed for the shredder. Pretty cool, when you can make a rear window fallout in a flash.

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h bl d h l k h

geeklord says: Jul 14, 2009. 9:34 PM REPWhy do chunks of ceramic whatever seem to be preffered over metal objects when it comes to breaking glass?

msw100 says: Jul 15, 2009. 9:47 AM REPA small bit of ceramic thrown at glass will break the glass,a small piece of metal wil l not, also pressing a sharp piece of ceramic against a car windscreenwill shatter it without much effort .Ceramic will also cut glass were as metal needs special treatment to do the same Ceramic cuts like a diamond.

Owlbear says: Jul 14, 2009. 11:13 PM REPceramics (or quartz) are usually actually harder than metals (ie quartz will scratch steel) and with a small bump like this one will more likely cause aspider web fracture which can be broken out.

geeklord says: Jul 17, 2009. 11:35 PM REPO, i see. thx

Jayefuu says: Jul 15, 2009. 1:59 AM REPPretty good ible! There's a mistake in the limitations section where you're talking about the layer of plastic in the windshield. You say 'showing you with glass'instead of 'showering you with glass'

Unit042 says: Jul 14, 2009. 9:32 PM REPDoes the homemade seat belt cutter and car window breaker actually work?If so, I could make one of these to calm my car paranoia (trapped by the stuck seat belt, and locked/immoveable windows, flames drawing nigh as preciousoxy en scarcifies. Panic builds while your shoes fill with blood....)

ravvip0 says: Jul 14, 2009. 6:06 PM REPwith step 2 and snapping the blade, most hobby knives have a bit which detach at the end (the black bit in your case) this bit usually has a slit in it, instead ofusing masking tape to catch the flying blade the idea is to take off the black plastic section, place the blade in the slit and snap it off that way - the blade wi llstay in the black plastic bit.

wupme says: Jul 14, 2009. 9:21 PM REPThat never worked for me, i never had luck with those plastik things on the end of the knive.Today i always use a plier (always got one around here) if i need to snap one of these blades.

But usually i use the metal knives where you can change the blade.The blades seem to hold much longer (better steel and thicker) and the knives handles better. I think one of those changeable blades should also begood for this project

bionicle72000 says: Jul 14, 2009. 8:38 PM REPi missed 7-11 so much

theRIAA says: Jul 14, 2009. 8:15 PM REPThis is just brilliant. I've seen a video of "ninja rocks" in use, I think I'll work fine if you smack it on the window, holding the end with your fingertips. Maybe aceramic point, or big ball on the end would be better?

DEFIANTLY making one! out of metal, a scalpel blade, and a big ceramic shard. The one in my car always falls off it's "quick release" attached to my turnsignal knob, so it's pretty useless.

killerjackalope says: Jul 14, 2009. 5:13 PM REPNice job, much better design than the giant plastic seatbelt cutters, my mother has one in the glovebox, because that's the closest place it 'll really go,considering the number of crashes she's been in this makes sense...