DIY LED car headlights!
This INSTRUCTABLE will go through the steps I am going through in the making of homemade fog lights for my car, a Hyundai Atos (sold as a Dodge Atos here in Mexico).
At first phase completion, my first 78 LEDs are dissipating 5.8 watts while my resistors only dissipate 0.85 watts, and the array is already powerful enough to dwarf the two front marker lights, which draw 3 watts each. My final objective is installing, at the very least, 300 LEDs at a total energy expenditure of 21 watts at the LEDs and 3.2 watts at the resistors.
All comments welcome.
Here's an index:
Introduction
Step One:
It seems silly to me to start working on something before knowing why.
Lets explore why I decided my Atos required more light fixtures:
A) The low beam setting is dim. Not in the sense of 'Wow: that top-end race motorbike emits more light than my car'; no, it was in the sense of 'Man, I'm driving behind a scooter that sounds like a never-ending fart because its light lets me see the potholes 20m ahead.' Matter of fact, some older fellows have told me they can't even tell from the inside if the lights are on or off.
B) The 'high' beam setting legally is a normal low setting, as these are defined by Mexico's Federal Road Legislation: it allows me to see the road just over twenty meters ahead and doesn't bother drivers moving the opposite way.
So yeah, I do feel justified to add more lights to my car.
Now, let's draw some objectives for this project:
A) The new lights should improve my overall visibility; supplementing and eventually leaving my headlights as 'secondary lights' for those times I enter the somewhat more dangerous sectors of Cancun.
B) The new lights should not add further strain to my car's tiny battery, tiny engine and tiny alternator.
C) The new headlights should not draw criminal attention to themselves. This should be achieved through either making them invisible at a cursory glance or by making them obvious and ugly. Personally, I'd prefer not making my car ugly on purpose, so my primary focus should be stealthy design.
D) The lights need a separate control from the default headlights, thus deserving the name of fog lights. This keeps me from being caught with my pants down in case a police officer pulls me over and asks why I'm driving with my headlights off.
E) Whatever the light needs, I cannot modify the aerodynamic profile of the front end. This includes symmetrical work and not blocking enough of the front grid to make the radiator work more than it already does.
F) The arrays themselves have to be designed so they cool themselves on the air. Most people design LED arrays like they were light bulbs, forgetting that LED's are heat-sensitive microelectronics that have to stay below 85Celsius to work their best.
Step 2: Exploration
The attached photographs include their own explanations, but I do need to make caption on the drawing: the image editor doesn't seem to like adding comments to GIF images.
Anyway, from a top view, it explores how could I place LED modules made from either 5mm white LED's (the yellow cones) or 3mm white LED's (the blue, more concentrated cones). The 3mm ones emit a tad less light per unit than the others, but by being their emissions more focused, they have a better throwing distance.
Schemes A, B C and D are schemes exploring designs using a single kind of LED's each. I wouldn't use A or B because I would need to make extensive arrays to get a good throwing distance; I wouldn't use C because it leaves me with no near field; however, I became interested in D because, although it still has no near field, it gives me the best far field of all the designs, as long as I make the beams cross at a distance between 15 and 20 meters.
Scheme E seems ideal: Good near field, good far field. Still, I kept brainstorming.
Scheme F seems an ideal
Scheme G will be my ideal to achieve: on the
Step 3: Procurement for Phase One
MATERIALS:
A) A hundred 3mm white LED's. Fifty were for the project; fifty were for my stockpile
B) Thirty-five 82ohm resistors (at a quarter watt)
C) Bakelite wafers.
I bought everything on Amazon
I have a bit of a stockpile on anything else I could need:
D) Around a dozen different types of glue (from hot glue to epoxy)
E) Around fifty 5mm white LED's
F) Assorted cables (different calibers of sound and microelectronics' cable). For best results, I prefer using thermocontractible insulation or glue-as-insulation ratter than electrical tape.
G) Clear acrylic paint. You might recognize it more easily as 'transparent graffiti'.
TOOLS:
B) A hacksaw blade
C) All kinds of electrical pliers: precision-cutting pliers, needle-nose pliers, round-bending pliers, wire-stripping pliers, et cetera.
D) A soldering iron
E) A mirror, a flashlight and my cell-phone's camera. At times, those were my only tools for looking at the work area.
F) Basic safety equipment: security glasses, an air extractor, et cetera.
SUBSTANCES:
I used FeCl3 on a 15% aqueous solution starting at 40 Celsius and kept at 33 Celsius (the ambient temperature) and stirred every now and then. The copper was gone within a half hour.
Step 4: First Phase: Component Construction
A)
B)
C)
Something else not to forget:
Step 5: First Phase: Area Preparation
Step 6: Phase One: Physical Installation
I'm sorry not to have too many images on this step, but my hands were sticky most of the time and my mobile phone , and LG MG800c "Chocolate" pretty much has to stay clean to 'want to' work properly.
Step 7: Phase One: Test Drive
A)
Problem is, the console ended up with so many buttons that I would be ashamed to install it until I figure out what to do with all of them.
B)
I like how my car's interior looks now, but my friends don't. I say it looks like the interior of a military aircraft (as seen on the movies), but my friends insist it looks like the entrance to a cheap *****house.
C)
Anyway...
About this Instructable:
I went to my mobile phone's authorized service, and after a few days without it, they called me and told me that it had humidity damage and, thus, the warranty was void. I celebrated that the warranty was void, picked the phone up, disassembled it at home, saw that the problem was some lime deposits built up around the inside of the multi-connector (power/USB/hands-free), and using a sharp needle and five minutes I got it to work as good as new.
I wish I had taken pictures of all I did to the phone and then made an instructable of it. Thing is, it is ratter hard trying to take pictures of a camera when it is the camera that you are repairing.
2) I finally took those beam shots.
3) I detached the LEDs from the marker lights' circuit
4) I put five more red LED's on the interior
5) I experimented with 10mm acrylic sheet.
Step 10: LED Brake lights
A) Leaving the resistors on the front of the design.
B) Not drowning your resistors in silicone or some similar kind of liquid-start chemical insulation. I used a thin insulation that had previously worked fine for flashlight design and that did work fine for a week and a few rains. Thing is, it didn't hold that well when I forded a flooded road: half of the lights began flickering before definitely dying a week later.
Ironically enough, the lights riding the lowest, those installed on the lower grill, have never hesitated.
Fortunately, these modules were made for my own use: I would hate my reputation to be tarnished if they had been returned from a client. I did waste a Sunday and more than USD$20.00 on these, though.Step 12: Continuing on Phase Two...
The first image shows how things look right now: two upper 'edge' arrays, each with 21 5mm LED (pointed forward, 5 degrees down and 5 degrees outwards), a central array of 60 LEDs at top density (pointed straight forward, replacing the twelve LED array around the Hyundai symbol) and two lower 'edge' arrays, each of 24 5mm LEDs (pointed about ten degrees down, five degrees inwards). Not counting the eighteen LEDs that sit under the hole where the Hyundai symbol used to sit, the array is consuming 10.5 Watts at the LEDs, 1.6 Watts at the resistors and draws precisely 1 Amp (1000 mA) from the source.
As of July 1ยบ, the last modules have been in place for a week and a half and it's been raining so hard that my car even looks like it had been washed: if these modules where about to fail, they would have already done so.
The Second image is a working image on the construction of the Upper 'edge' LED modules. They are mostly the same as in step four, except that I painted the boards before starting to work.
The Third Image shows my building of the center module.
The fourth image is a close-up on the capacitors I scavenged out of an old computer's power supply and connected to the central array. I used an scavenged bridge diode to isolate these caps and their array from the rest of the car and, of course, I had to tweak the resistor values for the central array.
The fifth image shows a couple of octagonal mirrors which I fitted into the hole for the central array. Not that useful, but they push out an extra little light.
The sixth image is the test of the array under the same conditions as always. I will need to reach the 300 mark before the light is good enough, but I'm glad that with only 102 actually pointed to the front, I do have decent illumination



