Anybody good with LED stuff?

Let me start off by explaining my project.

I am trying to create some bright LED spotlights (2) on my aluminum boat comparable to say a 400 watt Halogen light. This is for night bowfishing for carp. I have been researching around the net, but I am not sure what the best and brightest LEDs I should use.

I want it to run 12v for maybe 5 hours or so off two 60-75ah marine batteries.

I am pretty good with soldering and electrical stuff but not as good as how to wire them up and what resistors Id need to make it work.

I have found these that are pretty much ready to go

http://www.plasmaled.com/10mm_led.htm

and these but looks like might be a little more work.

http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&Page2Disp=%2Fspecs%2Fw18015_specs.htm


Id gladly pay for someone to fab some of these up for me.

Oh and I can trade some high quality fishing gear as well.

Jeff

I was reading about this before too, and frankly dont know that I figured it out.  But there were some calculators on the net that will tell you the resistance needed, and the color coding so you can buy it at a store.

Some example sites I just googled:

http://led.linear1.org/led.wiz
http://ledz.com/?p=zz.led.resistor.calculator
http://www.led-calculator.com/

Love to see what you come up with! 

This site had a good explanation (at least to me) on how to power LED's:

http://www.theledlight.com/ledcircuits.html

I also read this one:

http://www.horrorseek.com/home/halloween/wolfstone/Lighting/litlpo_PoweringLEDs.html

Jeff,
Those 5mm/10mm LEDs are not meant for illumination. You should be looking at things like Cree XR-E, SST90 and MC-E, Rebel, Seoul P7, etc.... For any LED lighting project, the most important things you'll need to worry about are power source, driver, and heat dissipation. LED may not be your best choice for your need. You should investigate other options before making your final decision. For example, I have some modified HID Maglight that is smaller than my hand. Bright and relatively long lasting. I don't know how much you want to get into LED lighting, but this hobby can be addicting. I got sucked into it for 3 years, trying to mod all kinds of flashlights to make them super bright. This forum would have all the info that you need for any lighting project.

www.candlepowerforums.com


ernest

I am just looking for something with low power consumption. One guy on a bowfishing forum used the Cree XP-G bulbs and looks like it would fit my needs. I just dont want to be hauling a generator and bulky light in my 14 foor boat. I am just looking for a solution and was hoping this would be the way.

Here is some pics of his setup

This place has a number of driver solutions that would fit your need if you're going to use 12v power source to power the Cree or similar high output LEDs.
http://www.taskled.com/

These high power LEDs do not need bulky batteries as a power source. Most ppl use Lithium Ion rechargeable batteries. Very light weight and compact. I hope you're thinking about using those 12v batteries because they're already in your boat.

For your project, I would recommend staying away from the 5/10mm LEDs because they would not do what you intend to do. LEDs and drivers can/will burnout within seconds if not properly heatsinked. Becareful.

You can also buy some relatively cheap high power flashlights, then all you need to do is mount them on your boat. These guys have high power LED flashlights for cheap, but read the reviews before you buy...
http://www.dealextreme.com/

Good luck.

lots of lights here too
http://www.magnalight.com/default.aspx

I've fooled around with LED bike lights.  There are lots of sites showing how people have wired up LEDs for bikes - you'll probably find more LED info by searching for bike lights instead of searching for bowfishing lights. 

My most recent one uses a 3 watt luxeon star that is like freaking daylight.  Check out luxeonstar.com  Looks like the latest one is the Luxeon Rebel.  The Rebel Tri-stars put out 315 lumens.  That is like arc-welder bright.  My old 5W was only 100 lumens. 

It runs for about 3 hours off of 4 AA batteries.  

The 3W doesn't get get too hot with the driver, but I used to have a 5W I was running straight off batteries and the heatsink would get too hot to touch.  Burned that one out.

Second try I got a 3W LED driver pre-made circuit board on Ebay to regulate the power.  It provides a steady 700 mA output for the bulb regardless of charge status on the batteries.  

Heatsinks from old computer processors are your friend.

Don't forget to order a lens when you order the bulb.  The lens is very critical to focus the beam.

So basically you don't need to monkey around with resistors.  Just buy a driver sized appropriately to your bulb.  If you get a 5W bulb, get a 5W driver.  From what I could find when I built my light, Ebay was the cheapest source for drivers.  The buckpacks from Luxeon are too expensive.

Recently the Army started using LED lights in the headlights of their bigger trucks.  They look to be the size of a 7 inch tractor bulb.  With maybe 10-12 half inch to 3/4 inch size bulbs in them.  We haven't had any go out that I know of so we really haven't had the need to take them apart.

Why re-crate the wheel? There are many different LED headlamps on the market. Cabelas has a great selection.
http://www.cabelas.com/cabelas/en/templates/index/index-display.jsp?id=cat20160&navAction=jump&navCount=1&cmCat=MainCatcat20712&parentType=category&parentId=cat20712

You can wear them on your head or you can mount one on your boat. Or both. No heavy batteries required. I use them for hunting, hiking, etc. and I have never run out of juice on a trip.