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niles
09-27-2012, 10:48 AM
Tools:
Phillips screwdriver
Soldering Iron with a good precise tip
Voltmeter is highly recommended so you can test your connections and stuff

Supplies:
500 Amber 3mm LEDs
100 1/4 watt Resistors 100ohm
Spool of small-gauge connecting wire or ribbon cable (like what’s used on computers)
1 large Phenolic Proto-board (I used part # EXPBRDLGPHEN)

Optional:
Turn signal housings: so you can build the LED ones without messing with your originals.

Additional Info:

If you have the original Honda flasher it will flash really fast. You have two options:
1) Buy an electronic flasher sold at any auto parts store
2) Mod the existing flasher like POS_carb: http://www.3geez.com/forum/showpost.php?p=1104893&postcount=10

I did option 2 and I love the adjustability, plus it applies to future plans for me. Thanks POS_carb! BTW I used a 100Kohm pot and it works perfectly (says 104 on it).

LEDs:
The ones I bought were marketed as Amber/Orange but they are more orange than anything. Always check the specs before deciding to buy. If there are no specs DO NOT BUY. You will need this information to make sure you use them properly. The most important part of all is that the LONGER lead is POSITIVE, or the LED will not work.

http://sphotos-b.xx.fbcdn.net/hphotos-snc7/408686_4696762578638_1798445_n.jpg

Resistors:
Will be different depending on how you decide to make your circuit. Be careful to not give your LEDs more current than they can handle or they will burn out. I will only provide the SAFE values, which is 100ohm in this application.

Layout:
The LEDs I bought handle 20mA and drop ~2V across each LED. So I am running 6 LEDs in series with a 100ohm resistor at the end. So each turn signal has 36 sets of these running in parallel. I found this fits perfectly inside the housing, right between the two screw holes. Each signal has 216 LEDs in it so you have some room for mistakes, but trust me, you do not want to fix any mistakes.

http://sphotos-b.xx.fbcdn.net/hphotos-prn1/644686_4696762658640_697920689_n.jpg
-Do this 36 times

Because of the limited space I chose to put the resistors on a separate board. The board I bought was 180 x 128mm, part # EXPBRDLGPHEN and it was perfect size for all my needs. The LED array is 8 x 27. Here is how I laid it out:

http://sphotos-b.xx.fbcdn.net/hphotos-ash4/408715_4696762458635_951854912_n.jpg

The thing I like most about this layout is that all the LEDs face the same direction so it's easier to assemble.

There are 4 columns of 8 rows, and then the end has 4 groups of six LEDs.
I connected all the Positive leads using connector wire so that only one positive wire was going to the light socket in the housing.
Each negative lead MUST go to its own individual resistor, and then all resistors will go to the ground on the signal housing.

niles
09-27-2012, 10:52 AM
Here is how the board fits in the light:
http://sphotos-b.xx.fbcdn.net/hphotos-ash4/421320_4694485201705_2109808570_n.jpg

Assembling the Resistor Array:
http://sphotos-a.xx.fbcdn.net/hphotos-prn1/536050_4694485721718_1445591296_n.jpg

I painted the board white, after assembly I wished I went with gray or black...
http://sphotos-a.xx.fbcdn.net/hphotos-ash4/301226_4694485841721_1397318249_n.jpg

And here you can see how it looks expanded out:
http://sphotos-a.xx.fbcdn.net/hphotos-ash4/399701_4694486281732_928024328_n.jpg

niles
09-27-2012, 10:57 AM
A good look at how I connected the LEDs:
http://sphotos-a.xx.fbcdn.net/hphotos-ash4/299433_4694490041826_1958139486_n.jpg
http://sphotos-a.xx.fbcdn.net/hphotos-snc7/391595_4694490321833_334830517_n.jpg

And the finished product without the lens. I am building new lenses out of clear privacy-textured acrylic. I am hoping it looks somewhat like the new Cadillac tail lights when finished. Additionally this does fit inside the original lenses as well.
http://sphotos-b.xx.fbcdn.net/hphotos-prn1/560484_4694489281807_993342278_n.jpg

2ndGenGuy
09-27-2012, 11:14 AM
Awesome work! Been wanting to do something like this for a while! Fantastic write-up! Went ahead and made this a sticky. I'm going to re-host the images locally in case they get taken down off of Facebook one day.

niles
09-27-2012, 11:24 AM
Thank you 2ndGenGuy!

2ndGenGuy
09-27-2012, 12:44 PM
Coming to the Portland meet? :)

niles
09-27-2012, 02:19 PM
I am going to try to make the photoshoot, but the rest of my day will be spent at the tattoo shop. I forgot which saturday the meet was...
http://www.3geez.com/forum/images/smilies/facepalm.gif

Vanilla Sky
09-27-2012, 02:23 PM
These look really good. I've had all but the board laying around my shop for years.

89HatchbackLxi
09-27-2012, 02:25 PM
Wow, Nice write up! Super detailed too!

I'll have to try doing this after I finish up with all the bodywork I'm doing on my car. I might actually try doing a sequential version of this.

Vanilla Sky
09-27-2012, 03:08 PM
I hosted the pictures on our server and made an entry in our How To section. You can see the finished How To here (http://www.3geez.com/forum/showthread.php?t=78848).

2ndGenGuy
09-27-2012, 03:55 PM
Oh ok sweet. Thanks for doing that.

niles
09-27-2012, 05:34 PM
These look really good. I've had all but the board laying around my shop for years.

I got the board from http://www.futurlec.com/protoboards.shtml
the part number is in the post.
Their prices are unbeatable on a lot of things...

POS carb
09-28-2012, 04:23 AM
http://www.futurlec.com/Protoboards.shtml
For some reason the link won't work on firefox if the P is lowercase

Hazwan
09-28-2012, 05:05 AM
Hey do you happen to know anything about regulating the current/voltage to the LEDs properly? I've done many LED conversions in the past except they all went out after about 2 years. From what I understand LEDs don't like the current/voltage spikes from the car charging system. I've made some research and I've got myself confused :tongue: So I was wondering if going with straight resistor setup like yours is a good idea or do I need some kind of regulation circuit so they would last?

Nice work BTW!

Vanilla Sky
09-28-2012, 06:42 AM
That's what the resistor board is for. LEDs handle voltage fluctuations very well, as long as they don't overheat. If you overdrive them, they overheat.

niles
09-28-2012, 07:09 AM
That's what the resistor board is for. LEDs handle voltage fluctuations very well, as long as they don't overheat. If you overdrive them, they overheat.


Hey do you happen to know anything about regulating the current/voltage to the LEDs properly? I've done many LED conversions in the past except they all went out after about 2 years. From what I understand LEDs don't like the current/voltage spikes from the car charging system. I've made some research and I've got myself confused :tongue: So I was wondering if going with straight resistor setup like yours is a good idea or do I need some kind of regulation circuit so they would last?

Nice work BTW!

I designed the lights based on 14.5 volts from the alternator instead of 12 volt, this also means they will appear dim when they are turned on without the car running.

And yes, my LEDs will probably not last forever, especially since I got them for such a good price. They are probably very sensitive to too much power.

If you want your LED lights to last forever you absolutely have to have some kind of regulation. They sell LED drivers fo $5 to $10 each that would be a good investment if you are doing a real classy project. But I figured with the turn signal, it only has a 50% duty cycle and is only used when I am turning (or broken down, fingers crossed) so I should get relatively good life out of them.

I could also go way into the voltage drop across diodes and how that affects what resistors you use but I feel it is best to use a tool like this link if you don't want to make you brain bleed with electronics calculations: http://led.linear1.org/led.wiz

niles
09-28-2012, 07:12 AM
And Vanilla Sky is right. They burn out when they get so hot internally that the silicon breaks down.

It's kinda fun to watch if you do it intentionally

Hazwan
09-28-2012, 07:23 AM
I've been reading too much advanced posts on HID planet and its driving me insane >< I don't even know if I'm gonna be fine if I designed my resistors to go with 14v instead of 12v.

So are you saying if I keep the voltage to the LEDs within the spec (in this case, 1.9v for mine) with proper resistors designed for 14v, they gonna be fine?

Vanilla Sky
09-28-2012, 08:28 AM
Ideally, you should have no problems. Deal Extreme is a good place for parts, as is eBay. Both carry DIY flashlight parts, and they make some VERY good drivers for high current LEDs that should suffice in this application. I would look into heatsinking any drivers, though, as they typically get pretty hot.

LEDs have a working range, and it's usually a range of at least half a volt. I know the Crees I work with will underdrive down to fractions of a volt, and will overdrive to 5 volts or more. The more you overdrive an LED, the shorter its life span. That's why passively regulated LED circuits can be hit or miss if they are designed improperly. A resistor based regulation circuit is 100% a passive circuit.

niles
09-28-2012, 09:02 AM
Yeah, all is correct information. As long as you work within the specs you should be rather safe.

Sorry for the scatterbrain - I just got over a cold.

I would like to add the the voltage regulator on an alternator is one of the most robust regulators you will find anywhere without a doubt. Additionally the battery is an amazing filter because it will absorb excessive spikes and smooth out voltage drops if any. If you have good wiring, your LEDs will be relatively safe.

As far as the math goes: a small jump in voltage = a large jump in current with passive resistor-based regulation

niles
10-26-2012, 03:36 PM
*Update:

I finally cut the plastic I had for the lenses. Will probably replace them with something less see-though or paint the inside part of the bumper white. Looks like privacy plastic is only private at a distance

http://sphotos-a.xx.fbcdn.net/hphotos-prn1/33865_4843128677699_1475910850_n.jpg

http://sphotos-b.xx.fbcdn.net/hphotos-snc7/396336_4843129197712_1319138324_n.jpg

gfrg88
10-26-2012, 06:21 PM
Any pics from a little farther back?


Looks good! But I do agree that maybe an amber paint/film might look better. Keep it up!

Civic Accord Honda
10-26-2012, 08:27 PM
i <3 leds!!! so doing for my crx except ill be keeping the amber lens cause i <3 amber!

niles
10-29-2012, 02:15 PM
I will take better photos once the second edition is completed.

niles
11-20-2012, 01:33 PM
Here is a sample of the new turn signal design. Improvements from the original design:
1) BRIGHTER!
2) Better Color
3) Less LED's to solder
4) Darkened the housing for a better look
5) Different lenses (pics soon...)

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0058_zpsbb18248d.jpg

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0060_zpsef082c1a.jpg

2ndGenGuy
11-20-2012, 02:10 PM
Oh yes! Can't wait to see them with the new lenses! Looks professional!

Vanilla Sky
11-20-2012, 02:11 PM
Nice. What are you running for emitters this time?

niles
11-20-2012, 03:24 PM
Nice. What are you running for emitters this time?

These LED's are "Piranha High Flux" so far I like them but don't think theyre good enough for such a flashy name. One noteable positive is that I subjected a single LED to 900mA (rated at 20mA) for over a minute! Turned kindof a red-orange color during but still works perfectly once returned to a normal power level. I have never seen a regular LED handle such abuse.


Oh yes! Can't wait to see them with the new lenses! Looks professional!

Thanks! The Second Edition lenses are like "sunglasses" for my signals which should match my bumper and make my car look sleek. There will probably be a Third Edition of lenses though... just a heads up depending on how the new onew work out.

Aesthetically I really want the LEDs to fill the entire turn signal cavity in the bumper but I did not want to figure out how to mount them so I am modifying the original housings for now...

And a bonus for eveybody who might want some made in the future: less LED's = cheaper! As always I want these lights to be bright and robust as F**** so I will not make anybody anything until I am sure they are good enough for me. But I will always let you know what I am using if you want to give it a go yourself.

That being said:

For the Second Edition turn signals, each lamp has 75 Piranha LEDs. I am running 5 LEDs in series with a 100ohm resistor. I will spare the math explanation again because there are plenty of great tools available online to help you figure out what you need for any application.

niles
11-21-2012, 12:37 PM
Here is a low-quality night shot. It was dark by the time I got them installed. I will try to get some better pics later today.

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0075_zpsvzhqebkq.jpg

2ndGenGuy
11-21-2012, 01:47 PM
Looks killer! :-o

niles
11-21-2012, 04:07 PM
Here is a daytime shot:

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0077_zpsf7531b57.jpg

Vanilla Sky
11-30-2012, 07:57 PM
Is that a head gasket set? If it is, let me know what the quality is like. I'm considering one for my head job.

dbales
12-28-2012, 01:01 PM
I love this. I have a set of turn signals for my cb opened up that I was partially blackhousing. I might be doing this on them before I seal them up.

niles
12-31-2012, 11:36 AM
Is that a head gasket set? If it is, let me know what the quality is like. I'm considering one for my head job.

Sorry Vanilla Sky, it is a valve cover gasket. However I would like to note that this valve cover gasket is the highest quality I have had so far. Got it from CarQuest, I would trust their head gasket, probably.

niles
04-21-2014, 11:49 AM
Mini-Update: I've been running the eBay Piranha LEDs now for a year and a half without issues.

niles
06-13-2014, 05:34 PM
Since I've added the body kit to my car (which required a post-facelift bumper to be installed) my pre-facelift LED turn signals looked funny in the large opening. This time I am trying out some ebay LED turn signals in the 88-89 housings with the reflector delete listed here: http://www.3geez.com/forum/how/104-clear-turn-signal-lens-88-89-year-accord-coupe-bumpers-only.html

I bought some of the brightest LED 1156 bulbs I could find that were a reasonable cost ($20 for the pair) and guess what: my superflux LED signals still outshine the competition, literally lol. Although they do come close.

Ebay LEDs are on the bottom and left, my handmade LEDs are on the top and right. I really prefer the distribution of the superflux as well.

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0254_zpsuduhgdrc.jpg

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0258_zpsuo8hcrus.jpg

http://i1286.photobucket.com/albums/a607/NilesHenke/Honda/DSC_0260_zpsr83ugj6o.jpg