How I Built My Own MTB Light

[BrewMaster]

Originally Posted by nappyt

Very cool project. You might want to check out LiPoly batteries for a later version. better power to weight ratio but the cost might hurt. I was thinking it would be good for an all-in-one helmet light. no cables to run or snag...

That's definitely an upgrade I am looking at. But with Li-Ion or Li-Polymer batteries, you must have a PCB to control the power output, otherwise they can supposedly catch fire or something. I've read this, I don't know it from experience. The PCB thing intimidates me because I don't know what I would need or how it would work. I guess someone here could tell me or one of the electronics shops listed in this thread.

[destroyer]

I just skimmed the thread so I'm not sure if someone mentioned it. But some thermal paste will conduct electricity, which could be a problem if the LED's legs are touching the thermal paste. I would recommend arctic silver ceramique, it's cheap, works great, and doesn't conduct electricity.

[OffRoadie]

Originally Posted by BrewMaster

That's definitely an upgrade I am looking at. But with Li-Ion or Li-Polymer batteries, you must have a PCB to control the power output, otherwise they can supposedly catch fire or something. I've read this, I don't know it from experience. The PCB thing intimidates me because I don't know what I would need or how it would work. I guess someone here could tell me or one of the electronics shops listed in this thread.

I think you can buy the Lithium batteries that are "smart" that have electronics integrated with them.

[destroyer]

I've bought a good amount of LED's from these 2 places:
http://www.allelectronics.com/
http://dragonmodz.net/

DragonModz has a smaller selection but there service is top notch and they ship with USPS so shipping cost me about $1.40 for my last order.

Here are the DragonModz UV LED's I used in my current computer case, and they are still bright 2 years later.

[coldbrews]

What is the name of the place that rebuilds old batterey packs, the name was mentioned in the old thread about making this light.

[Chewyeti]

sick job sam!!!

My dad is an EE, i will see if he and i can come up with a nice compact housing design for a helmet mount.... and then i will make one

[BrewMaster]

Originally Posted by coldbrews

What is the name of the place that rebuilds old batterey packs, the name was mentioned in the old thread about making this light.

http://wcbatteryrebuilders.com/

from this thread.

Originally Posted by Chewyeti

sick job sam!!!

My dad is an EE, i will see if he and i can come up with a nice compact housing design for a helmet mount.... and then i will make one

Dude, we could build a few of these together. Let me know what you guys come up with.

The hardest part of building this light is finding an old heat sink. I had to take an old one from a Pentium II at work and cut it in half to get one the right size.

[sailcalifornia]

Originally Posted by Dino Brown

Sailcalifornia- Nice of you to join us again! Where you been? Get yourself a light Junior!

Coleko- Ford Electronics is also a VERY cool store. Clean... Great selection... knowledgeable staff (i.e. can direct you to other places if need be). In many way, I like it more than Orvac! With that said, the selection at Orvac (including junk parts, overruns, obsolete parts etc.) make it tough to beat!

I already have an niterider HID, have been doing the tuesday night Blackstar rides the last 2 weeks

[Schecky]

Originally Posted by BrewMaster

http://wcbatteryrebuilders.com/

from this thread.

They have my light right now. I will post a report when it is done.

[COLEKO]

Originally Posted by BrewMaster

The hardest part of building this light is finding an old heat sink. I had to take an old one from a Pentium II at work and cut it in half to get one the right size.

Dang a little while back I tossed all kinds of heatsinks out in the trash. I still have a small box of some left over from past projects. Ive seen heatsinks at the Cypress swapmeet and ive seen them at Oxmans surplus in La Mirada. Oxmans is a cool place.

[OldDogDan]

Here's a good shop if you live in North County or SW Riverside County.


http://www.temecelectronics.com/temec-index.html

[destroyer]

Originally Posted by BrewMaster

The hardest part of building this light is finding an old heat sink. I had to take an old one from a Pentium II at work and cut it in half to get one the right size.

Take your pick!

http://www.allelectronics.com/cgi-bi...eat_Sinks.html

http://www.goldmine-elec-products.co....asp?dept=1195

[BrewMaster]

I wish I knew about all of these good electronics stores before I built my light. Probably would have saved me money and shipping. I am still looking for reliable, tough connectors, so I may check some of them out. Radio Shack's offerings just aren't good enough.

One other improvement I would like to make would be a low battery indicator light. Anyone know how I might add something like this?

[COLEKO]

Originally Posted by BrewMaster

I wish I knew about all of these good electronics stores before I built my light. Probably would have saved me money and shipping. I am still looking for reliable, tough connectors, so I may check some of them out. Radio Shack's offerings just aren't good enough.

One other improvement I would like to make would be a low battery indicator light. Anyone know how I might add something like this?

What kind of connector are you looking for?

[BrewMaster]

Originally Posted by COLEKO

What kind of connector are you looking for?

DC-DC power connector. The connectors I have been using either are too hard to insert, too hard to remove, or are too tough to crimp and end up cutting the wire.

I'd like to solder the connection and then put the insulation over the top. In this pic you can see the pink connectors coming out from the battery wires. They suck and need to be replaced with something more robust. I am afraid to unplug them because they break so easily, which defeats the purpose of a connector.

[COLEKO]

Originally Posted by BrewMaster

DC-DC power connector. The connectors I have been using either are too hard to insert, too hard to remove, or are too tough to crimp and end up cutting the wire.

I'd like to solder the connection and then put the insulation over the top. In this pic you can see the pink connectors coming out from the battery wires. They suck and need to be replaced with something more robust. I am afraid to unplug them because they break so easily, which defeats the purpose of a connector.

I whould use somthing like a deans plug.. If you come to the loop next Thursday Ill give a male female plug to try out.
http://www.wsdeans.com/products/plugs/index.html

They also make a Micro plug and you can pick those up at Hobby People or any hobby store.

[destroyer]

Originally Posted by COLEKO

I whould use somthing like a deans plug.. If you come to the loop next Thursday Ill give a male female plug to try out.
http://www.wsdeans.com/products/plugs/index.html

They also make a Micro plug and you can pick those up at Hobby People or any hobby store.

I was typing the same thing... You beat me too it. I guess you raced RC Cars too.

[COLEKO]

Originally Posted by destroyer

I was typing the same thing... You beat me too it. I guess you raced RC Cars too.

I still do just not as often. Infact im working on my stuff right now for a race later this month. I really hate connectors but if I had to use any on my cars they were deans plugs. I direct solder all my connections on my car.

[OffRoadie]

Originally Posted by BrewMaster

One other improvement I would like to make would be a low battery indicator light. Anyone know how I might add something like this?

You would need to find the voltage for NiMH that indicates that the battery is low. You then have a circuit that detects the low voltage and hits the LED. They might make IC's for this sort of thing.

EDIT: Here's one designed for Lithium Ion batteries, but might be able to be adjusted for NiMH.
http://www.linear.com/pc/downloadDoc...63,P2133,D1290
Linear Technology LTC1998

Another one: Single Supply Under-voltage/Over-voltage IC
http://www.l