5W... uh, 3W LED Headlights at less than $40 each

[glv]

that is super cool, I may have to give that project a shot. Thanks for the link!

 

[julesa]

Thanks very much for that link, Bikeraider! I hadn't thought of using copper plumbing -- copper conducts heat very nicely. I may go that route if my ideas for cast aluminum don't work out (but I've already put in so much time on this I'll be really disappointed if I can't make it work).

 

[Drunkskunk]

Thanks very much for that link, Bikeraider! I hadn't thought of using copper plumbing -- copper conducts heat very nicely. I may go that route if my ideas for cast aluminum don't work out (but I've already put in so much time on this I'll be really disappointed if I can't make it work).

Casting aluminum may work for you, but have you considered casting with aluminum welding rod? The stuff from harbor freight isn't expensive, and melts around 590F. Its denser, stronger, and conducts heat better than Aluminum.

 

[julesa]

Hi Drunkskunk,
You mean that alumiweld stuff, "weld aluminum with a propane torch," right? Thanks very much for the suggestion, I'll keep it in mind.

If I can just get the foundry a little hotter, I can use free sources of cast aluminum, though. Lately I've been dropping all my 'fun' money on batteries, dual kickstands, relays, Anderson connectors, wire, heatshrink, switches, LEDs, loktite, misc. hardware, etc, etc. etc. so right now "free" sounds pretty good.

I actually had a near-success last night after widening the blower intake of my foundry to allow more airflow. Unfortunately I poured too fast and most of the aluminum pooled around the top of the sprue without going in. I have another mold prepared, so I can just recycle the aluminum from last night's pour and try again tonight. Might have needed to be a little hotter, too -- next time I'll wait a little longer after it's all melted, and dig into the foam sprue a ways before the pour so the metal doesn't have to burn so far into it before it gets any decent head pressure, like this:

http://www.buildyouridea.com/foundry/lost_foam_howto/lost_foam_howto.html

 

[TylerDurden]

Pic below shows 3W MR16 LEDs mounted in headlight lenses, compared to 55W halogen driving lights. Not quite as bright, but damn bright for 3W.

Got the 7" headlight enclosures from JC Whitney:
http://www.jcwhitney.com/autoparts/...Id-100000442298/Pr-p_CATENTRY_ID:100000442298

 

[etard]

This is an interesting subject to me as I would like to have some nice bright lights for riding trails at night. I am also rigging up some lights for a wrecked motorcycle that I ride.

Any updates Julesa? I would like to know how the foundry turned out. Did you see the video Frank put together on his sandcast sprocket?

Keep up the work guys, I will be posting my lights soon.

 

[julesa]

Sorry for the slow reply, I was out of town for a few weeks. I got the foundry hot enough to do a good pour, but I underestimated how slowly the EPS foam would melt and underestimated the head pressure I would need... so it turned out pretty badly but now I know what I need to do for next time. Then some other projects demanded my attention. I should have those done in the next three weeks or so, then I can get back to making my LED fixtures.

I didn't see the sandcast sprocket... that sounds like a tricky job!