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Aerodynamic bike helmet!

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Make your helmet more aerodynamic while revealing your inner artist! This instructable will introduce you to composite manufacturing and get you closer to being Lance Armstrong.
 
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Step 1: Sketch the shape. Dream big!

Drawing inspiration from both the fish and a nearby airfoil, I put a piece of butcher paper underneath the helmet so I could sketch a few ideas and see how they looked. Here's a parts list for this project:
-Fiberglass cloth, epoxy resin, slow cure catalyst (can buy at Home Depot; ask for fiberglass boat supplies)
-Foam sheets you can cut with a hotwire (plus a hotwire cutter; or make your own)
-String, masking tape, hot glue, 5 minute epoxy, string, masonite scraps (see step 2)
-spackle (same kind used for drywall is fine) and spackling/putty knife
-metal bonding compound (should be sandable)
-Sandpaper (80-100 grit), razor blade/scissors for cutting fiberglass cloth
-latex gloves, safety glasses, respirator with organic vapor/HEPA filters
-a BIKE HELMET you're ready to convert into a MASTERPIECE!!!

Step 2: Cut out the desired cross-section.

Scissor out your desired cross-section from the butcher paper and trace it onto a piece of 3/16"-thick masonite. I used a bandsaw to cut the masonite (with safety glasses, of course). Use a file to smooth out the edges of your masonite cutout.

Step 3: Fit the cutout to the back of the helmet.

I prototyped the shape using paper again.

Step 4: Add a sheet of foam on either side of the cutout.

Sandwich the masonite in between two sheets of foam. Using a hotwire, shape the foam so that it matches the contours of the helmet. Gaps of 1-2 cm are ok.

Step 5: Make two more cross-sections.

Dust off your imagination and use it to envision a cross-section that's one foam sheet away from the original one. I chose to cut this piece to match one of the vents in the back of my helmet (see photo) so that I would have an easier time with assembly. After you've decided on the shape, cut out a second identical version to go on the outside of the other sheet (e.g., in the picture we can see the cutout that goes on the right side of the helmet; a copy of this cutout will be attached to the opposite foam face).
probetox1 year ago
Original and nice, good job pal
zomfibame1 year ago
That thing is very cool, in it's own funky way. I am diggin' it. ... but I doubt that it's any more aerodynamic than the helmet was before all that work had been done. still, it looks cool n' original and that is just as good as aerodynamic as far as I'm concerned. well done.
Adum241 year ago
Hmm, Alien anyone?
onrust1 year ago
That helmet looks like its doing 60mph just sitting there!
No offense but I dont want that on my head
bootdsc5 years ago
(removed by author or community request)
you are right, twice. once because Hal is a meth dealer and two because the other guy cheated
Guess its to hard to check the date..I keep getting reply's almost a year later.
i replied yesterday, so fret not.
Hal is weird. I like the show thougn
eggmcmffn4 years ago
the way you've got that rig, its so aerodynamic you could almost fly. pretty goofy dude.
you have to think about cross wind and the mast and sail of a helmet this is. the goblin helmets go to one point and is nestled nicely between the shoulder blades, allowing a significantly less surface area in all directions, even from the standard position of being head on in a wind tunnel. there are many preconceived notions in the field of aerodynamics. it's "dynamic." cyclist make turns, the wind is different in many areas on the bike and in a peloton, and even in a time trial. sorry if this came off mean, i make that mistake frequently. i only want to proliferate, not put down.
looks cool, but it could brake your neck if you fell.
reedz5 years ago
Good idea but most helmets are made to be as aerodynamic as possible in the factory.
ahh a lot of helmets are designed not to have stupid bits sticking out so they dont pull you over or get ripped off of your head in high winds, but a lot of the £40, £50 helmets around at the moment are designed to look like the aerodynamic helmets professional cyclists use in competition. the problem is that the wind resistance professional helmets reduce is only noticable in professional conditions - and the cheap helmets are merely copies of the style - a bit like having bmxs, but not for tricks - theyre entirely for looks. the style's moving a bit further away from this at the moment, however - with pointy bits at the back of the helmet being flattened and smoothed to give the helmet a more urban look. gawd im a bike helmet geek............
yiucycle6 years ago
thanks, now i going to loss another 3 sec on my next TT event. thanks for the great work.
KronoNaut6 years ago
What a great idea for costuming.
fstedie6 years ago
Ruined a perfectly good helmet...
dan8 years ago
hmm, perhaps you want a 'breakaway' tail design where the tail is only weakly attached to the helmet?
Visitor dan7 years ago
It is more likely that you do not want to make any modifications to your helmet. I've forgot the details already but a few years ago there was an incident in a downhill skateboardign competition where a young skater died because he had made an "aerodynamic extension" to the back of his helmet. The extension acted as a fulcrum and the helmet broke his neck. *snap* Instant death.
severnclay8 years ago
Ditto - the reason its so hard to get a certified time-trial helmet is that if you're in a crash where your head needs to roll, the tail will f**k you.
axs8 years ago
Robyn, you are AWESOME!
austin8 years ago
It looks cool but it woulndt reallly make it any more aerodynamic
HeavyCream8 years ago
You're better off without it if you crash, that tail will break your neck.
ranex8 years ago
thats a lot of layers you put on that thing, how heavy is it compared to a regular hemet
aerospatial (author)  ranex8 years ago
It's pretty light, actually, since it's just a shell (and since I used lighter fiberglass (7 oz. per sq. yard) for the second and third layer). You hardly notice that it's there.
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