BMW lighted roundel, too!

[pozo_izquierdo]

Thanks to Bruce Hodges, I got more farkle idea. Which I needed to extend somewhat of course, sorry....:o

Anyway, here is the full story with 57 pics.

http://picasaweb.google.com/pozoizquierdo/LIGHTEDBMWROUNDEL

regards

[hschisler]

Very nice, Ari -- as always. :cool:

[jorawro]

Nice job Ari :)

[Redleg]

Ari,

You are truly the farkle king!!! Great job.

[Wolfgang]

What a great way to brighten up the long dark winters in Finland. I really admire your ideas and the patience to turn them into reality.

Greetings from S.California.

Wolfgang

[pozo_izquierdo]

Thanks to everyone but really the credit for the original idea goes to Bruce. His written instructions were really good as such but I thought some people might feel safer tackling a project if there are some pictures enclosed as well.

And documenting something that someone has already done and especially that you have to make two similar units is quite easy when you finally are doing your unit #2. Documenting unit #1 would just produce a lot of "OOPS" and "dammit" type of expressions and not so nice pics...At least in my case...:p

Best regards

[dshealey]

Nice job Ari, and good pictures.

Should anyone else try this, one can use up to 5 LEDS in series with one dropping resistor, rather than parallel with a resistor for each LED.

Not sure what LEDs you used, but 470 ohms per led seems a little to low, as that is about 27 mA, most LEDS last longest at about 20 Ma., or approx. 680 ohms per. You may have used high brightness LEDS that require higher current though.

To put 5 LEDs in series, at 13.5 volts and 20 Ma, one would use a single resistor of approx. 500 ohms, smaller for higher current if the LEDS are rated for it.

Automotive brake light assemblies typically use multiple sets of 4 LEDS in series, with one resistor for each set.

[pozo_izquierdo]

Nice job Ari, and good pictures.

Should anyone else try this, one can use up to 5 LEDS in series with one dropping resistor, rather than parallel with a resistor for each LED.

Not sure what LEDs you used, but 470 ohms per led seems a little to low, as that is about 27 mA, most LEDS last longest at about 20 Ma., or approx. 680 ohms per. You may have used high brightness LEDS that require higher current though.

To put 5 LEDs in series, at 13.5 volts and 20 Ma, one would use a single resistor of approx. 500 ohms, smaller for higher current if the LEDS are rated for it.

Automotive brake light assemblies typically use multiple sets of 4 LEDS in series, with one resistor for each set.

You are correct David and that's exactly what I was aiming at. I went to my local electrics shop and asked the guy that I want to connect 5 leds in series and what type of resistor I would need (if any) when I'm feeding them max 14 V (or 13,5 whatever). He replies to me that these ones will not light up at all because 5 x 3,6 V = 18 V which is more than my 13,5 to 14 V.
Then he started calculating that I could connect 3 leds in series and use one kind of resistor and the other two would need another kind and so on...
At that point I told him that OK, I will connect them parallel, no big deal, just get me the the needed resistor per each. He was calculating and calculating and after about seventh double checking he came up with this 470 ohms.

Now I am no electrician! (Electricity is smoke to me, you know...) So I trusted the guy especially that I have bought some leds from him before. But these bigger leds (rated at 3,6 V / 26 mA) seem to burn very white, indeed. I mean they were supposed to be amber in color (like the little ones) and that's why I had to use the amber plastic to turn the color closer to amber.

Oh well, lets see how long the leds will burn...

Thanks for your comments anyway:)

Regards

[dshealey]

---------------He replies to me that these ones will not light up at all because 5 x 3,6 V = 18 V which is more than my 13,5 to 14 V. ----------------------------------------
Regards

Yes, those are some high voltage drop LEDs! High brightness ones do tend to be high voltage drop though. "Normal" LEDs tend to be 0.7-1.2 volt drop.

[Raffe]

Hello Ari !

Nice work, i did another version. I put 15 leds from the inside of the black plastic. so when the led are on it looks like sun beams around the BMW mark.
Saw it i think on the german BMW site.

Regards from Sweden

Ralf

[pozo_izquierdo]

Hej Raffe,

that sounds interesting, too! Did you cut some slots on the black base or how does the light come out?
Do you happen to have any pics?

Regards

[Raffe]

Hello Ari !

I drilled holes in the black plastic, and put the leds in from the inside. I tried to get some photos in my first tread. But i couldnt get them in, probably did something wrong. But i send some pictures to you by mail if you want. I havent yet taken any photos in the dark. Try to do that tomorow if possible.

Regards from Sweden

Ralf

[pozo_izquierdo]

Ok Raffe , looking forward to the pics. Always eager to see new farkle ideas!!

BTW, I'm passing through Stockholm on Monday May 21:st on my way home from LT-Treffen in Berlin. Staying overnight Sun-Mon in Karlskrona and aiming for Viking Mariella leaving at 16:45 for Helsinki from the harbor.
Perhaps we could shake hands somewhere en route and I could check your leds in person in case you fail to attach the pics..;)

regards

[Raffe]

Hello Ari !

I tried to take some pictures in the dark, it didn´t go to well. I need to put the camera on something steady, try to do that tomorow in the evening.
Anyway it would be great to meet you before you go with the ferry to Finland. I will try to send you some pictures tonight by mail.
I have been trying to post some pictures in this tread, but i can´t make it work.

Regards from Sweden

Ralf

[pozo_izquierdo]

Hello Ari !

I tried to take some pictures in the dark, it didn´t go to well. I need to put the camera on something steady, try to do that tomorow in the evening.
Anyway it would be great to meet you before you go with the ferry to Finland. I will try to send you some pictures tonight by mail.
I have been trying to post some pictures in this tread, but i can´t make it work.

Regards from Sweden

Ralf

Hej Raffe,

I guess the problem with your picture posting is the extremely high resolution of them (2816 x 2112 ) I reduced them to 640 x 480 pixels and took the liberty to show them to a larger group.
Your installation looks nice and the light effect is quite stunning! How did you solve the waterproofing?

regards

[Raffe]

Hello Ari !

Why didn´t i think of that, ill try to change the resolution with some other pictures. Regarding the waterprofing, i did use hot melted glue. One thing i forgot that i have to do. Is to make a small slot at the lowest point of roundel. To let the water sip out.

I also would like to say that i got the idea from the German LT site. Sorry i cant remember the persons name who came up with original idea

Anyway a big thank you to him.

Regards from Sweden

Ralf

[bruce2000ltc]

Thanks to Bruce Hodges, I got more farkle idea. Which I needed to extend somewhat of course, sorry....:o

Anyway, here is the full story with 57 pics.

http://picasaweb.google.com/pozoizquierdo/LIGHTEDBMWROUNDEL

regards
Nice work Ari,

The amber LEDs I used are clear until power is applied, then they emit a high intensity amber light. Usually LEDs that have bodies the color of the light you want will have their color washed-out when they're powered on.
Also, I sanded (roughed-up) the edges of of my lenses to help spread out the light around its circumference. I like your use of amber plexiglass for the lens...great ideas are sometimes born of need.

Great photos and descriptions!

Bruce Hodges

[Swan]

Very very perfect jobs.
Compliments.