led strip..

[billcreller]

I was thinking ( didn't you see the smoke ?)  about a strip of led's for a third brake light, to put on the top-inside area of the rear window, on my El Camino. Red of course.  Not just for something to do, but the normal tail lights are in the rear bumper, very low for good visibility.  Seems like a good idea (?)
  I know zero about led's....any suggestions on what to use, and what is required to power them ?
Are some capable of more lumens/ candle power etc ?

 All dumb ( uninformed) questions....

[stingray_65]

Bill,
Are you planning of fabricating your own strip?
Or are you going to use a ready made something or another?
Or both?

 A quick search turned up these

http://www.oznium.com/led-flex-strips.

not much more than a red and black wire to hook them up.

LED's come in all sorts of intensities, all but the dimmest are far brighter than the old 1157 tail light bulbs.

The shape of the top of the LED has a lot to do with it's apparent brightness, they are dome shaped to act like a lens. Some can only be seen head on, while others have a wide dispersal. Some are even "frosted" like a soft white light bulb to diffuse it even further.

I think a 3rd brake light is a good idea, any LED's that you use will be better than not having one.

A small strip of 10 or so jumbo's (10mm) will be pretty intense and quite noticeable.

Check out this tutorial on building an array.  a handy fella like yourself should be able to design his own after seeing how they are typically wired.
http://www.electronics-lab.com/projects/mcu/018/index.html

[EL34]

There are so many sites selling colored LED light strips and red 3rd brake lights

The red material needs to have that diamond shape so that the light gets dispersed
Otherwise, with LED's you just end up with a bunch of little dots of light.
I am not sure where you would even get the red plastic material???
It's not worth trying to make one from scratch, IMO

Here one for $35
http://www.ecrater.com/p/10568118/04-06-chevy-colorado-led-3rd-brake

I did a quick google for LED 3rd brake light and saw tons of choices.

I did take my dome light and build a small circuit baord with 6 high output LED's
I only did that because I have left dome lights on before for a couple days and drained my battery down.
Plus the white LED's look really nice and white inside the car

The high output white LED's I sell are really nice for white lighting projects.
3 in series with a 47 ohm current limit resistor works perfectly on 12 volt DC

[PRR]

Yes, run 3-light brake-lights! Tailgaters today do not react to just two lights.

Also the Camino's main lights are much lower than a Volvo/Toyota.

Yes: buy don't build. There's actually rules about total and specific brightness and spread. Not that you would get cited for, but if you don't get very close to Standard Lamp then it won't look right to the guy behind you.

Problem is finding GOOD stuff; apparently there is a lot of junk on the market.

Facing these questions on my brother's 1941 Plymouth. It was stock with no turn signals and only one brake-light (in the high center license-plate holder). Bro converted the running lights to 2-filament for run/brake, but didn't get it right. He had a turn-switch but it was a cheap POS. I got him a better pos which also has 4-way function. While this could have all been done with the 2-fil tail-lights, we'd already added bolt-on lamps to keep the turn separate from the run/brake, since wiring was simpler.

> top-inside area of the rear window

When 3rd-eye lights first came in, we retro-fitted inside.... but that throws a lot of red glare off the glass into your rear view mirror. Better if you can cut for a semi-seal to the glass (easier on a Camino's flat glass than some of the cars I ran).

My 1991 CK2500 pickup has a 3rd-eye on the metal over the rear window. Such a casting might fit the Camino. Dunno if you'd want to drill, or if something could be done with super-magnets.

Bro's Plymouth has the additional fun of still being 6V. 1158 lamps are still NAPA-available, but 6V flashers are special order after a stupid-look. Our add-on turn lamps are still 12V bulbs and sure don't have much impact on 6V; I have to find a short 6V 2+A lamp to fit.

I'm probably going to use LEDs for dash turn indicator but have to re-compute for 6V and remember that this car is positive-ground.

[billcreller]

Thanks for all the responses.  After looking at the options, the ready-made one for pickups looks like the way to go.  I could also put one on my '92 Chevy pickup.  I have a 3rd brake light, but it would sit in the bottom area of the window, and is kinda big, and I didn't like it, but I did wire in the little module that came with it.  I guess I could have tapped into the brake light switch, but didn't spend time thinking about it until I had the module wired in.   I'll try the one from Ecrater, and if it doesn't fit the roof line, I can use it on the truck, and try a different one.

  PRR, I do remember that the old Chrysler products with 6V systems had a positive ground.  Ford did also, even into the 12V cars for a few years..   Not easy to adapt an alternator 

  It looks like to me, that some LED lights would work good for emergency lighting in my house.  We lose power a few times a year, and I have to fire-up the generator for power. but just having lights would help until the generator was online.  We lost power last week, for around 25 hours.

[billcreller]

I found that the light in the add wont work for me, because of the roof line on the El Camino.  I did see one that's a narrow strip, that people are using on pickup trucks. A narrow strip would work on the inside of the back window.  It's way too long though, like 49 inches.  I'll just keep looking.......

[Ritchie200]

There HAS to be something you can use in the JC Gypney Catalog!!!!  Are they still in business?

Jim

[billcreller]

Yeah Richie, they are still in business.   Not many auto parts though, just accessories & add-on junk.  They still send me catalogs after all these years, but I don't know why !  They do have lights of all kinds though.  I'll have to see what they have.  Thanks for the suggestion !

[billcreller]

Hey stingray 65, thanks for the Oznium site !   I ordered a red light bar from them, for a 3rd brake light.  It's 20 inches long, but can be shorter if cut in the correct places.  Maybe it will be OK at 20 inches.  I plan on mounting it on the top edge of the rear window glass.  Should work OK...  




I still have the stool that my picture was taken on in 1934, so maybe I should get it taken again, now that I'm a bit older.....

[Ritchie200]

Can you still bend your leg up that far - I know I can't! At least not without falling off the back.... 

Jim

[billcreller]

Luckily I'm still quite flexible !

[billcreller]

Good thing I'm not in a hurry for the light bar.  They got the order on the 3rd, didn't ship until the 5th, charged me for Priority Mail, and I haven't seen the package yet. (4 days)  I can ship guitar parts to Hawaii quicker than getting a package from Colorado . The USPS tracking is mostly non-existant. 

I'll have to think twice about ordering any more items there...

[EL34]

I got a new old car recently.
A 97 Subaru Legacy Outback
I am in love with this car

Anywho, I replaced all the interior lights with the High Powerd 5mm LED's that I sell
Two Map lights and two dome lights

I cut copper boards on my CNC and put multiple LEDs on each board
The boards replace the bulbs

It takes a bit to get used to how white the light is compared to bulbs which are very yellow

I'll have to take a night image of the car interior
It's lit up like a stadium  

[billcreller]

Never owned a Subaru, but worked on a few for friends.  Good cars, from what I know.  Your lights sound interesting.  I'm thinking about a small, not too bright strip, to go above the row of toggle switches in my airplane, with some sort of shield to keep the lights on the switches ,and not in my face.
  Not really legal from an FAA standpoint, so it would be easily removable, with a banana plug on each end etc.  The instruments are all lit with post lights, but no lights on other stuff...

[stingray_65]

Not to HiJak here,but..

how does one dim a strip of LED's

Current limiter?

how bout with a pot? Variable dimmer?

Like if Bill wanted to adjust the intensity of his Non-FAA strip, or if I had a Lucite bass guitar...

[EL34]

how does one dim a strip of LED's

Reduce the current, but I am not sure what components would be best to do that?

When I set up led's, I measure the current and set the current limit resistor so that I am running about 25ma per led
So a fixed resistor determines the brightness of my strips.

If you had a rheostat pot of the correct value and power rating, that would work in line with your fixed current limit resistor.

In my fancy bike lights, we use AMC7135 current limit chip boards
The AMC7135 chips have 3 legs and can control up to 350ma of current.

One leg controls the flow of current
The fancy driver boards use pulse width modulation to control the AMC7135 chip pin
So turing the chip on and off at different rates can create different current levels through the chip.

Some of the solid state guys may know of some other way to do this.

BTW, in my automobile LED lights I am operating 3.6 volt leds on 12 volts so you put 3 LEd's in series which is 10.8 volts
Then you just need to drop 12v - 10.8v = 1.2 volts across your current limit resistor which comes out to 48 ohms per set of 3 led's
http://www.el34world.com/php/LedCurrent.htm

[EL34]

Hey Bill
I added a post on how to use my 5mm leds on 12 volt car batteries
http://www.el34world.com/Forum/index.php?topic=12842.msg119830#msg119830

gonna take some pics of the interior of my Sooby lit up at night
It's very impressive

[billcreller]

OK Doug, I'll check it out.

My strip for the 3rd brake light arrived today finally.   It's about 1/2" wide, and 20" long, and really bright, so it should do the job fine.