Let there be more light

[syntaxjunkie]

So I'm just about ready to drop semi-serious coin on some sort lighting apparatus. I've gathered from related posts that HID is most likely the way to go. So here are my outstanding issues:

1. Should I get a helmet-mount or bar mount light, or both?

2. If the answer is both, is one HID and one non-HID acceptable?

I eagerly await your opinions...

[gopherhockey]

I'd go HID helmet, but one that can do both is nice. Thats how I'll go next time around.

I had one HID and one non and the light color differences gave me a headache and just didn't work well. It might have just been me though, but having both lights melt together better seems to work best. Two HIDs can be spendy though.

Next time I'm going with a Light & Motion ARC Li-Ion headlight. The Niterider is an excellent light, but sits too front heavy on my helmet.

If you can still find them, the Niterider Storms are a steal of a deal, however!

[jeffgude]

I bought the Niterider Storm helmet mount. It's more than adequate for riding at a reasonable speed. You don't reallty need a bar mount to supplement it.

[bigwheel]

I just can't let this thread go by without mentioning the homebrew option.

Somebody please correct me if I am wrong, but in our un-scientific tests, an over-volted (14.4 volts on a 12-volt bulb) 20-watt MR-16 produces substantially more light than a 13-watt HID. Granted, you will probably only get 1 season or less out of a bulb, but it is cheap and lightweight to just carry an extra bulb.

Note: I am running a 35-watt bulb on my bars, but that is definitely overkill (read: fun).

If you don't mind a bit of tinkering, you can build a nice setup for about 50 bucks. It will probably only be about a half-pound heavier than the expensive HID setups. If you don't mind carrying the extra weight of a sealed lead-acid battery, you can do the whole thing for well under 30 bucks, with only a couple hours work.

For a guy like me that crashes a lot, it is also a nice feeling that you can replace all of the possible broken stuff for about 10 bucks. Batteries are the most expensive part, and they will survive a crash.

This winter, I plan to write a HOW-TO paper that describes several solutions. Your choice will depend on:
1: how much money you are willing to spend
2: how much weight you are willing to carry
3: how much work you are willing to do
If you are interested in home-brew, please hang on. I promise I'll have a HOW-TO ready in plenty of time for next season's rides.

The store-bought lights are definitely nice and compact, but there is another option.

Even if you are planning to buy a nice set of HIDs, you may want to wait until spring. In addition to avoiding having batteries laying around your basement all winter (read: losing capacity), you may find out that next year's products are worth the wait. Battery technology is continuing to improve. Also, the HID inverters and battery monitors are getting cheaper and better.

[EmL34]

I just use a helmet mount and I think it works just fine. Not sure if I can be spotted by planes @ 10K feet, though.

[jeffgude]

If you don't mind a bit of tinkering, you can build a nice setup for about 50 bucks. It will probably only be about a half-pound heavier than the expensive HID setups. If you don't mind carrying the extra weight of a sealed lead-acid battery, you can do the whole thing for well under 30 bucks, with only a couple hours work.and if you don't mind the smell of burning plastic. ;)

[noise_is_life]

This winter, I plan to write a HOW-TO paper that describes several solutions.

I can't wait to see it Bob.

1. I'm just too much of a cheap-skate to pay for an HID unit.
2. I hate that blue light.
3. My Digital Evolution works OK, but I would definitely like more light.

[syntaxjunkie]

Thanks for the input, folks. I admire the DIY aesthetic, but I've learned that trifling with electicity--even at low wattage--is best left to projects not in close proximity to my cranium. I'll have to do some looking to see about a nice, relatively lightweight HID unit for the lid.

[Ish]

I second John's reccomendation - go for a L&M HID. I have a nightrider and agree that it hangs to far forward which makes you helmet want to keep falling down. I have heard the L&M's don't do this.

Just go with a HID on the lid and you will be good to go!

[soupboy]

...ARC yesterday. Holy f'ing crap...what a difference vs. my Niterider Digi Evo. My old light is like trying to hold a Bic ligher in front of me with one hand while riding.

Truth be known, nothing beats the Lupine Edison - but then again, that's a whole 'nuther bike.

Sean

FWIW - there was a Performance e-coupon that was letting you get the ARC NiMH for about $300 net of discount.

"...You can get wit dis, or you can get wit dat...you can get with dis, or you can get wit dat...or you can get wit dis cuz this is kinda phat...Can't beat that wit a bat..." - Black Sheep

[redwood]

If you are interested in home-brew, please hang on. I promise I'll have a HOW-TO ready in plenty of time for next season's rides.

Sign me up - I can barely wait!:banana:

[Don Youngdahl]

Just a short rant on my Light & Motion HID 04 when used as a helmet mounted light. It does a good job of lighting up the trail, but it falls down badly on user-friendliness. This light has two design deficiencies that are inexcusable for a first class product in this price range.

There is no quick disconnect clamp to remove and re-attach the headlamp from a helmet. The two alternatives are to: a) unfasten and re-attach that cumbersome velcro strap that is so difficult to fish through the helmet vents; or b) remove the lamp from the mount with a small phillips screwdriver, reaching down through a vent. This leaves a loose small screw and washer that will take a long tweezers and some patience to re-install, or to use a 6-32 nut in place of the lamp to hold the screw in place. Good luck in not misplacing the nut if you've had the lamp mounted for several days.

My second beef with this unit is the connecting cord from lamp to battery, which is a long cord that disconnects at the battery only. When I put the battery with cord attached in my fanny pack, the heavy battery quickly migrates to the bottom of the pack. Then if I want to take off my helmet & set it down for some reason, I have to fish the battery out of the bottom of the pack, or remove the pack also & simply keep it tethered to the helmet. With the pack now tethered to the helmet, it's a bit of a juggling act to get going again. Which do I put on first? How simple it would be to have the disconnect plug about10-12 inches from the lamp, within easy reach to connect or disconnect, as it was on my old Marwi. This problem I can fix by installing a plug where I want it, but when I pay high bucks for a product like this, it shouldn't need modification to make it handy to use.

End of rant.

Don Youngdahl

[berrywise]

I just can't let this thread go by without mentioning the homebrew option.

Somebody please correct me if I am wrong, but in our un-scientific tests, an over-volted (14.4 volts on a 12-volt bulb) 20-watt MR-16 produces substantially more light than a 13-watt HID. Granted, you will probably only get 1 season or less out of a bulb, but it is cheap and lightweight to just carry an extra bulb.

Note: I am running a 35-watt bulb on my bars, but that is definitely overkill (read: fun).

If you don't mind a bit of tinkering, you can build a nice setup for about 50 bucks. It will probably only be about a half-pound heavier than the expensive HID setups. If you don't mind carrying the extra weight of a sealed lead-acid battery, you can do the whole thing for well under 30 bucks, with only a couple hours work.

For a guy like me that crashes a lot, it is also a nice feeling that you can replace all of the possible broken stuff for about 10 bucks. Batteries are the most expensive part, and they will survive a crash.

This winter, I plan to write a HOW-TO paper that describes several solutions. Your choice will depend on:
1: how much money you are willing to spend
2: how much weight you are willing to carry
3: how much work you are willing to do
If you are interested in home-brew, please hang on. I promise I'll have a HOW-TO ready in plenty of time for next season's rides.

The store-bought lights are definitely nice and compact, but there is another option.

Even if you are planning to buy a nice set of HIDs, you may want to wait until spring. In addition to avoiding having batteries laying around your basement all winter (read: losing capacity), you may find out that next year's products are worth the wait. Battery technology is continuing to improve. Also, the HID inverters and battery monitors are getting cheaper and better.
Bob,

What do you think about maybe hosting a class on this? Everyone could have a list of ingredients they would need to get behorehand. Everyone could bring any of the tool they could. Have a general location. Everyone shows up and builds their light and then have a group ride sometime in the near future after that with their new lights?

I think that would have quite a bit of interest (myself included) if you would be willing to play teacher on something like that. Not sure if it would be possible but just a thought.

[noise_is_life]

Bob,

What do you think about maybe hosting a class on this? Everyone could have a list of ingredients they would need to get behorehand. Everyone could bring any of the tool they could. Have a general location. Everyone shows up and builds their light and then have a group ride sometime in the near future after that with their new lights?

I think that would have quite a bit of interest (myself included) if you would be willing to play teacher on something like that. Not sure if it would be possible but just a thought.
I made a similar suggestion elsewhere. He promised a HOWTO sometime this winter which I have no doubt will answer all questions in great detail.

[flombe]

Just a short rant on my Light & Motion HID 04 when used as a helmet mounted light. It does a good job of lighting up the trail, but it falls down badly on user-friendliness. This light has two design deficiencies that are inexcusable for a first class product in this price range.

There is no quick disconnect clamp to remove and re-attach the headlamp from a helmet. The two alternatives are to: a) unfasten and re-attach that cumbersome velcro strap that is so difficult to fish through the helmet vents; or b) remove the lamp from the mount with a small phillips screwdriver, reaching down through a vent. This leaves a loose small screw and washer that will take a long tweezers and some patience to re-install, or to use a 6-32 nut in place of the lamp to hold the screw in place. Good luck in not misplacing the nut if you've had the lamp mounted for several days.

My second beef with this unit is the connecting cord from lamp to battery, which is a long cord that disconnects at the battery only. When I put the battery with cord attached in my fanny pack, the heavy battery quickly migrates to the bottom of the pack. Then if I want to take off my helmet & set it down for some reason, I have to fish the battery out of the bottom of the pack, or remove the pack also & simply keep it tethered to the helmet. With the pack now tethered to the helmet, it's a bit of a juggling act to get going again. Which do I put on first? How simple it would be to have the disconnect plug about10-12 inches from the lamp, within easy reach to connect or disconnect, as it was on my old Marwi. This problem I can fix by installing a plug where I want it, but when I pay high bucks for a product like this, it shouldn't need modification to make it handy to use.

End of rant.

Don Youngdahl
Can you say JET Lites? Wire disconnects easily right on top of my helmet while wearing full finger gloves. Nice beam coverage. Adjustable quick release mount. 3 light levels from 20 watt lamp. Battery tucks nicely into pocket on Camel Bak. Smart charger. All CHECK!

I ride with a JET Lites 20 watt Phantom Single Beam w/Smart Switch and it works fantastic! All for $260. Shipping included in that price too. Check them out at http://www.jetlites.com/. They rate highly at MTBR.com, if that matters. Not a homebrew, but you can DIY by calling and talking to someone about the type of riding you plan to use it for and they will recommend the suitable model (and not the most expensive to make a sale). The guy I spoke to has ridden up here and is familiar with the type of terrain and the type of foilage, etc. I read they have great customer service if you happen to have a problem. Highly recommended.

[ThorSonic]

I did a little research on lights for night trail riding. One point I found that was made more than once is that you need to have the same output of the two lights. Since I haven't done any night trail rides, I don't know. I'm going to be using a 10watt NiteRider spot from 1996 as my bar light and a Cat Eye HL-EL 400 LED light as my back up light, which has a simple helmet mount and on the fly adjustment. I bought it as a back up light, but I hope that it will work with the NiteRider for letting me see around corners and such during a night ride. I still need to find out. Now, I would really like an LED flashing backup tail light. My current one mounts on my arm and doesn't flash.

Richard

[bigwheel]

I made a similar suggestion elsewhere. He promised a HOWTO sometime this winter which I have no doubt will answer all questions in great detail.
Scott and Pat,

I'm still promising that how-to. My work crunch ends on Friday, so I'll hopefully get some time after that to work on it.

Meanwhile, there have been some recent discussion on mtbr. A couple of them seem to know what they are doing, and one of them posted a FAQ. I read the MTBR forums now and then, but am currently "lurking" -- not posting.

http://www.mtbr.com/techtalks/
Search "homemade lights" on "discussions".

[el gueche]

i got a flashing tail light at penn for under $10.00 works great - adjustable position, fast flash, slow flash, and constant - double a and will last a good long time - i concur on jet lites - purchased the i6 - excellent product - went with the low priced model due to financials - only problem is run time

[tedsti]

There is no quick disconnect clamp to remove and re-attach the headlamp from a helmet. The two alternatives are to: a) unfasten and re-attach that cumbersome velcro strap that is so difficult to fish through the helmet vents; or b) remove the lamp from the mount with a small phillips screwdriver, reaching down through a vent. This leaves a loose small screw and washer that will take a long tweezers and some patience to re-install, or to use a 6-32 nut in place of the lamp to hold the screw in place. Good luck in not misplacing the nut if you've had the lamp mounted for several days.


My solution to the same problem with my TurboCat set-up was to buy a new helmet (which I wanted anyhow) and just leave the light on my old one. My old helmet is now my dedicated night riding helmet. My new helmet, which this scenario helped me "justify", is my daytime helmet.

Ted

[syntaxjunkie]

Can you say JET Lites? Wire disconnects easily right on top of my helmet while wearing full finger gloves. Nice beam coverage. Adjustable quick release mount. 3 light levels from 20 watt lamp. Battery tucks nicely into pocket on Camel Bak. Smart charger. All CHECK!

Sounds good. Looks good. But it would mean making an exception in my ongoing boycott of companies who persist in running stupid ad campaigns. Tough call...

:fool: :banana: :laugh:

[Trapper]

Hi Guys,

I was searching the web for a decent mounting system to upgrade my DIY light and came across your thread. Figured I'd share the love a bit. Here's what I did with a converted maglight. (http://www.trappersplace.com/maglite/) I need to update the site with some more info but it has worked well for several riders around here.

What I need to include:
- Finally figured out how to get Mag's switch out of the body without destroying it. Remove the rubber cover and use an allen wrench to loosen the screw that is way down in there. I haven't tried to reuse this switch yet, but may do that this weekend.
- A cheap ($7.00) Bell handlebar light can have it's quick release removed and mounted onto the mag body so you can use it for road riding. I do this for my "after dinner fitness rides" where I put in a 35 watt halogen and ride hard for an hour. It freaks out drivers, but I want to be noticed by them in the dark. (It doesn't blind them, it's just the wierd movement of a bright light coming at them that does not compute. They usually pause at an intersection and wait for me to get there just to see what is going on. Perfect.)

We have a thread on BikeMojo.com (http://www.bikemojo.com/speak/showthread.php?t=8327&highlight=maglight) that you may find interesting too.


If you have questions you can PM me since I have the email option turned on for that.

[redwood]

I'm having trouble with my niterider storm HID. every time i hit a bump the light goes from the blue/white color to red. If I jog with it it happens every step. I sent it back on warranty, they replaced the bulb, but the problem remains.

Is this just the way HIDs are?

[Ish]

I'm having trouble with my niterider storm HID. every time i hit a bump the light goes from the blue/white color to red. If I jog with it it happens every step. I sent it back on warranty, they replaced the bulb, but the problem remains.

Is this just the way HIDs are?

I don't have that problem with mine. I also have a nitrider HID (the helmet mount one). Could it be a connection problem?

[redwood]

Hmmm.....:mad:

[redwood]

Building bike lights is my new obsessive hobby. Of couse, i didn't realize how bad I wanted to build a bike light on the cheap until I spent $300 on a perfectly good NR Storm. O well - this is hobby; it's for entertainment.

Anyway, I've taken Bob Shepard's tip and got the optronics driving lights from JC whitney. I have the Philips 20W MR16 bulb that is supposed to put out the lumens of a 35 W bulb. I've ordered a 14.8V 4000mAH Li-ion battery from batteryspace.com. I've learned from the forums on that website that I will need to build a softstart device so that Li-ion battery doesn't shut itself off with the initial current surge of passing electricity through a cold light bulb. So I've orderd the capacitors and resistors and what not to put that together.

Total cost of my new system should be about $90, and I think it will be blindingly bright and very light. I'll post when I have some results.

Any advice from the experts?

[bigwheel]

Building bike lights is my new obsessive hobby. Of couse, i didn't realize how bad I wanted to build a bike light on the cheap until I spent $300 on a perfectly good NR Storm. O well - this is hobby; it's for entertainment.

Anyway, I've taken Bob Shepard's tip and got the optronics driving lights from JC whitney. I have the Philips 20W MR16 bulb that is supposed to put out the lumens of a 35 W bulb. I've ordered a 14.8V 4000mAH Li-ion battery from batteryspace.com. I've learned from the forums on that website that I will need to build a softstart device so that Li-ion battery doesn't shut itself off with the initial current surge of passing electricity through a cold light bulb. So I've orderd the capacitors and resistors and what not to put that together.

Total cost of my new system should be about $90, and I think it will be blindingly bright and very light. I'll post when I have some results.

Any advice from the experts?

Hey Zach,

Sounds like it's going to be a nice setup. You'll find that an over-volted 20w Masterline puts out as much or more light than an HID. Also, when over-volting, the light is a lot whiter, compared to the yellowish color that you get from a normal halogen.

Can you post a link to the battery? I went to batteryspace.com, but couldn't find the 4000mAH 14.8v battery.

I'm not familiar with Lithium batteries, but based on the spec sheet for the 2000mAH Li-Ion, the peak for these suckers is going to be 16.8 volts. That seems like quite a bit of over-volting for a 12v bulb, so you might want to carry a spare bulb, and be prepared to make some major changes if you start blowing bulbs.

I have had good results over-volting with 14.4-volt NiMH (about 15.5v actual). My only bulb failure was the result of an endo, and not because of "natural causes". Nonetheless, I always carry a spare bulb just in case.

The metal optronics light works well, but I suggest adding a set screw to keep the case from falling apart in the middle of the ride. You will also find that the Phillips Masterline bulb has a curved front, and is slightly longer than other brands. As a result, it takes a little bit of shoving to get the bulb into the optronics fixture.

BTW, JC Whitney recently had the optronics lights on sale for around $12 for 2. I don't know if they are still on sale.

Another hassle with the optronics case is that there is no room to fit a switch, so you'll have to put one somewhere else.

As far as soft-start, I haven't found a cheap&easy way to do this yet. I've considered making a current limiter based on something like an LM-317 IC, but haven't tried it yet. If you hook up an ammeter to the leads, you will find that when you turn the light on, the current jumps to about 3x the normal amount until the bulb heats up (1/4 second). Anyway, your battery will be fine to direct connect, but your bulb life will be shortened.

One more thing: If you are testing your setup in the cold weather, your battery capacity will be a lot less than on a summer ride.

I am still planning to write a couple how-to papers. The first one, describing the verycheap&easy&heavy version, then the second one getting into the ugly stuff.

Good luck, and let us know how it turns out.

Bob S.

[redwood]

Bob - you're right. As of this morning, the Li-ion battery pack is not on the website. They still sell it as part of this kit (scroll down to bottom left to see the battery)


http://batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1369
I got the battery w/ smart charger for $63. Weight on the battery is supposed to be 380 gms or so if i remember correctly.

Some people on the batteryspace forum had problems with the Li-ion batterypack and 20W halogens (current-sensitive circuit breaker inside the battery pack would switch off the batterypack if it was hooked up to a 20W bulb, though it worked fine with a 10W), so the moderator recomended this soft start circuit:

http://mysite.verizon.net/~tbrown59/gif/softstart.gif

The idea is that current is only super high when the filament is cold, so the softstart won't deliver full power until the filament is hot.

All of the sudden battaryspace is selling halogen/li-ion kits, so I think the combination must be feasable. As far as bulbs burning out quick, I hope the softstart buys me a little extra bulblife.

I'll keep you posted.

[robc]

Hey all,
I was just looking at batteryspace.com again, and I notice they now have 13.2 and 14.4 batts premade for fitting into water bottles. Where were these last year when I was learning how to solder my own packs!? Dang. Their cost right now is just about the same as it would cost to solder your own pack from loose cells. (Less if you factor in the shrinkwrap, connectors, and your time). Looks like they have been reading their forums about people making packs for biking.
Anyways, just thought I'd post in case anyone wants a super quick power solution for their homemade lights. The Powerizer batts I have came in lower than their stated ratings - I get around 4000 mAh instead of the rated 4500, but for the price I can bring a spare.
Using the optronics light housings and some of these batts, one could build a killer system in one night for pretty cheap.

Bob, are you going to try to use one of the Optronics housings for a helmet light? I would like to see your clever ideas for a mount! Your handlebar mount worked great for me. Thanks, and keep the ideas coming! I am also looking forward to your DIY article on this subject.

Here is the 14.4 batt link:
http://batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1276

-Rob

[bigwheel]

Last summer, when I was building my lights, I didn't see the water bottle fixture, or the Li-Ion batteries. They are both nice, and will make it a lot easier for homebrew lighting. It's also interesting that batteryspace is selling complete light setups. However, I'm surprised that they are using the MR-11 bulbs, when the MR-16s put out so much more light.

The soft-start circuit certainly looks simple and small enough. Thanks. I have a few MOSFETs laying around, so I'll give it a try.

It looks like they are now making 5500mAH C NiMH batteries and 2500mAH AAs (check www.thomas-distributing.com). This is a step up from what they had 6 months ago. I don't doubt that the price will drop in another 6 months. I still contend that if you don't mind the soldering, AA packs have a significantly better capacity to weight ratio than any other NiMH battery size and are cheaper. However, with the Li-Ion packs getting cheaper, this may be the way to go. Also, keep an eye on the Lithium Polymer technology, which is getting popular with the RC airplane folks.

Rob, I really like the optronics lights for the handlebar mount, but I don't plan to rig one for my helmet. Being kind of tall, I tend to hit a lot of branches at night, so I need a rugged setup. The PVC+rubber mount that I'm using has worked well, so I'm not planning to change it. The main drawback with PVC is that melts when you use it with a 35-watt bulb. However, I'm happy with the 20-watt helmet setup, so that's not a problem for me.

For handlebar mounting, I use a 3/4inch conduit clamp (around 6 for $1.00 at Home Depot). I shoved some shrink wrap (Home Depot) around the clamp to keep from scratching my bars, and replaced the screw with a wing-head screw (also at Home Depot) for a poor man's quick release.

Bob S.

[redwood]

An update on my progress and a question for Bob or whomever:

I don't have the 14.8 Li-ion pack I ordered yet, but I got impatient and wired the philips masterline 12V 20W bulb to a 12V NiMH battery Pack I have sitting around. I took the slapped-together halogen as well as my Niterider Storm HID light out on the streets at night. My brother and I compared the two lights, and both agreed without doubt that my halogen makeshift thing was brighter. That's with only 12V. The NiteRider has a 13.2V pack. The halogen light output should approximately double when I get a 14.8V battery! Wow!

The test might have been slightly biased because on city streets the ambient light makes it tough to see less intense light. So maybe the intense 8 degree halogen spot stood out, while the NiteRider perhaps had a more diffuse beam pattern that simply was tough to notice under the street lights. But even factoring that in, I still think the halogen was brighter. I don't know what the beam spread on the NiteRider is.

Also, I have a question. I want to rip open the 12V NiMH battery and add 1 or 2 more cells to make it 13.2 or 14.4 Volts. My charger puts out 15V 400mA. Will this be big enough to charge a 14.4V battery Pack?

Thanks for the help,
zach

[bigwheel]

My brother and I compared the two lights, and both agreed without doubt that my halogen makeshift thing was brighter. That's with only 12V. The NiteRider has a 13.2V pack. The halogen light output should approximately double when I get a 14.8V battery! Wow!

The test might have been slightly biased because on city streets the ambient light makes it tough to see less intense light. So maybe the intense 8 degree halogen spot stood out, while the NiteRider perhaps had a more diffuse beam pattern that simply was tough to notice under the street lights. But even factoring that in, I still think the halogen was brighter. I don't know what the beam spread on the NiteRider is.

Also, I have a question. I want to rip open the 12V NiMH battery and add 1 or 2 more cells to make it 13.2 or 14.4 Volts. My charger puts out 15V 400mA. Will this be big enough to charge a 14.4V battery Pack?

Thanks for the help,
zach

Zach, It's god to see someone else confirm what I think I've been seeing. I'm pretty sure that an overvolted 20w MR-16 is significantly brighter than a 13w HID. However, I don't want to be too quick to shoot my mouth off without doing some formal testing. Things like beam angle, color of ambient light, and amount of peripheral light make a big difference in what we think we are seeing. Maybe we can get a photo buff that has some decent light measuring equipment to help us out with a formal test.

As far as the 14.8v pack being *twice* as bright as 12v, I'm not sure that will be the case. The formula for brightness vs voltage vs lifespan comes with a note that it is only intended for values within 10~15 percent of the rated voltage. I know that it is a lot brighter, but am not sure if it is twice as bright.

As an example of formula "out of bounds": On my lights, I hooked up a "low beam" switch, which re-wires the battery at half of the voltage. According to the formula, there should be almost zero light output at that voltage. However, in reality, it still produces a decent amount of light (although well less than half as bright as with full voltage).

Nonetheless, you will get a lot of light at 14.8 volts.

As far as adding cells to your pack:
1: You will need somewhere around 17.3 volts to charge a 14.4v NiMH pack. Note that this varies by battery type and manufacturer.

2: It is a bad idea to add cells to an existing pack, unless you are using nearly identical cells (brand, capacity, age and charge/discharge characteristics).

[bigwheel]

BTW, I tried a bench test of the batteryspace.com soft start circuit:

http://mysite.verizon.net/~tbrown59/gif/softstart.gif (http://mysite.verizon.net/%7Etbrown59/gif/softstart.gif)

(Note that I used a different MOSFET than the one in the diagram, but I doubt it will make much of a difference.)

It sort-of works, but I'm not positive that it completely eliminates the current surge.

When you turn on the switch, it indeed takes about a half-second before the light gets to full brightness. However, it seems to spend most of the time time before you can see the light at all, then ramps up very quickly.

I put an ammeter (the analog type with a needle) in line and tested it again. The ammeter would over-swing, before settling in on the stead-state current. This might be momentum in the meter, but I suspect that it is still pumping in a lot of current when the bulb is "almost" on. I also tried increasing the size of the capacitor to exagerate the slow-start. In the exagerated test, it took a very long time for the light to start burning, but there was very little time between when you can just start to see light and when the bulb was full-on.

So, I suspect that there is still a current surge, although it is probably less than without the soft-start circuit.

I plan to check out the spec sheets, to see if there is anything special about the MOSFET in the diagram. If not, then I will rig up a new test to record the peak current (my measuring equipment doesn't have this capability built in).

Bob S.

[bigwheel]

(I apologize in advance to all non-geeks reading this.)

As a follow-up to my previous post, I rigged up a crude way to measure peak current when the light is turned on. The numbers are probably way off, but the general result is what I'm interested in.

Results of crude test using 20-watt bulb and 12-volt (13.1 actual) 4ah SLA battery: Note that my measuring circuit ate up about 2 volts.

Steady-state current was about 1.25 amps.

Without any soft-start logic, the peak current is 5x the steady-state current. (about 6 amps) (I expect that the surge will be worse with a NiMH battery, which can produce higher currents.)

With the soft-start circuit, peak was about 2.5x the stead-state current. (about 3 amps)

Then, I modified the soft-start circuit. Peak was about 1.1x the stead-state current. (about 1.3 amps)

Here's the mod:

Add a 5-ohm resistor between the source and drain leads of the MOSFET. This puts the lamp on "low-beam" immediately when the switch is turned on. By the time the soft-start kicks in, the light is already warmed up, so there is almost no surge. The resistor will only be used for the half-second at start-up. So, you probably will only need to use a half-watt resistor.

Bob S.

[redwood]

Thanks a lot, Bob. That's a very clever solution. I don't have a breadboard or anything to set up and pull apart circuits easily, and I definately don't have your E&M knowledge. So I think you just saved me untold hours of general agravation and searing my fingers on the edge of my soldering iron!

Zach

[bigwheel]

Tonight, I made another helmet light so I could take pictures for the documentary. Here's the highlights:

[JHM]

(I apologize in advance to all non-geeks reading this.)

Add a 5-ohm resistor between the source and drain leads of the MOSFET. This puts the lamp on "low-beam" immediately when the switch is turned on. By the time the soft-start kicks in, the light is already warmed up, so there is almost no surge. The resistor will only be used for the half-second at start-up. So, you probably will only need to use a half-watt resistor.

Bob S.

Nice solution Bob. I had the idea to add a parallel inline resistance path with a two position switch and manually control the bulb warm up time, but your idea is way better. I guess when you actually build this stuff, you arrive at better solutions than the people who just daydream about it.

[nigel]

Im still waiting for Bob to show up at a trailwork night with a new 10000 watt setup and a car battery on a trailer behind him!

Bob i think im going to have to hire you for a light setup since i doubt ill be getting any premades this year, whats your rate big guy :)

Oh yeah and i have an two extra batteries for the niterider HID setups, one is the bottle one and the other is the flat one......can you use those at all?

[bigwheel]

Im still waiting for Bob to show up at a trailwork night with a new 10000 watt setup and a car battery on a trailer behind him!

Bob i think im going to have to hire you for a light setup since i doubt ill be getting any premades this year, whats your rate big guy :)

Oh yeah and i have an two extra batteries for the niterider HID setups, one is the bottle one and the other is the flat one......can you use those at all?

Hey Doug,

I'm starting to get a handful of "prototypes". You are welcome to have one of them. All we need to do is rig up a battery pack that fits your needs.

Thanks for the offer on the niterider batteries, but my latest setups need a cold-fusion reactor. Depending on the battery setups are and what kind of shape they are in, we might be able to scavange them for a low-power helmet light for you.

Bob

[redwood]

Bob's mentioned a few times that the best Amp-hour to weight ratio in NiMH Batteries is in the AA size. I looked at some specs and that seems to be right. I saw this set of 2300mAh AA batteries, but they are flat tops.

http://batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=245

Does anybody have experience or knowledge about whether small batteries like this with out soldering tabs can take the heat of soldering directly to the batteries? If so, THe whole 24 pack put in parallel pairs and then all the pairs in series seems like it would be a very light and cheap solution.

[bigwheel]

Bob's mentioned a few times that the best Amp-hour to weight ratio in NiMH Batteries is in the AA size. I looked at some specs and that seems to be right. I saw this set of 2300mAh AA batteries, but they are flat tops.

http://batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=245

Does anybody have experience or knowledge about whether small batteries like this with out soldering tabs can take the heat of soldering directly to the batteries? If so, THe whole 24 pack put in parallel pairs and then all the pairs in series seems like it would be a very light and cheap solution.

Zach, I solder directly to non-tabbed AA batteries all of the time. Even though I've made several bad mistakes (including soldering a short circuit and not knowing where the smoke was coming from) :shocked:, I've never had a problem with the packs.

I standardized on 7.2v, 4600mAH packs (12 batteries per pack). My packs also cross-wire each pair of batteries.

The trick is to:
1: Use as hot of a soldering iron as possible. You want to get on and off as quickly as possible. I use a 260-watt gun, although you can probably get away with a 60-watt iron. If you use too small of an iron, you end up holding the iron to the battery so long that the heat gets a chance to transfer into other areas of the battery and wreck things.
2: Sand the ends of the battery before starting. I use emery cloth.
3: Put a drop of solder on each battery before you get started. It isn't quite "tinning", but it makes it a lot easier to solder the wires.
4: Only work for a couple seconds on a battery, then move to the next one. If you make a mistake, work on the other batteries first, then go back and fix the mistake.

Finally, be aware that not all 2300 mAH batteries are the same. Some manufactures tend to exaggerate more than others. Here's a good comparison:
http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM
Note that Sanyo and Energizer perform closest to as advertised, but powerizer (the ones sold by batteryspace.com) do not. I currently am using Tenergy batteries from all-battery.com, which are not included in the comparison, but performed reasonably well in my own tests, considering you can get them for $1.23 each.

[tedsti]

Batteryspace now has HID lights for sale.
http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1332
http://forums.mtbr.com/showthread.php?t=78470

[redwood]

[QUOTE=redwood]I think you just saved me untold hours of general agravation and searing my fingers on the edge of my soldering iron!


You can also sear fingers by holding a 10 Ohm resistor in place with your fingers and then connecting it to a 14.8 V battery and a cold halogen bulb :shocked: .

[bigwheel]

I think you just saved me untold hours of general agravation and searing my fingers on the edge of my soldering iron!

You can also sear fingers by holding a 10 Ohm resistor in place with your fingers and then connecting it to a 14.8 V battery and a cold halogen bulb :shocked: .

I hope you are kidding. First off, I suggest 5 ohm, (I tried 10, but there was a bigger current jump). However, even with the 10-ohm resistor: Assuming the bulb acts as a completely short circuit (unlikely), 14.8 volts / 10 ohms = 1.48 amps. 1.48 amps x 14.8 volts = 22 watts. 22 watts for 1/2 second shouldn't be enough to burn your fingers. Now, if you keep the resistor in place for a minute or so, that's a very different story.

Ted, good catch on the HID. Coupled with the water bottle pack, it looks like you can rig up an HID with off-the-shelf components for under $200.

[redwood]

I hope you are kidding. First off, I suggest 5 ohm, (I tried 10, but there was a bigger current jump). However, even with the 10-ohm resistor: Assuming the bulb acts as a completely short circuit (unlikely), 14.8 volts / 10 ohms = 1.48 amps. 1.48 amps x 14.8 volts = 22 watts. 22 watts for 1/2 second shouldn't be enough to burn your fingers. Now, if you keep the resistor in place for a minute or so, that's a very different story.

Ted, good catch on the HID. Coupled with the water bottle pack, it looks like you can rig up an HID with off-the-shelf components for under $200.


The risistor got very hot very fast. Previously, with an identical 10ohm 1/2 watt resistor in series with a 20w halogen and a 12V battery, I released the resistor's magical smoke in about 5 seconds. Wasn't holding on to that one though!

When I actually put the soft start together I'll use 2 of the 10ohm resistors in parallel.

[redwood]

problem solved

[redwood]

After 6 hrs of screwing around with the soldering iron and getting very confused and frustrated, and generally begining to question my basic understanding of E&M, I realized that the 1/2/3 labels on the mosfet on th circuit diagram from batteryspace don't match the 1/2/3 on the mofset. :crazy: Many expletives of joy and frustration. It's been a five beer emotional rollercoster tonight, but finally the sofstart works!:banana:



zach

[bigwheel]

After 6 hrs of screwing around with the soldering iron and getting very confused and frustrated, and generally begining to question my basic understanding of E&M, I realized that the 1/2/3 labels on the mosfet on th circuit diagram from batteryspace don't match the 1/2/3 on the mofset. :crazy: Many expletives of joy and frustration. It's been a five beer emotional rollercoster tonight, but finally the sofstart works!:banana:
zach

Zach, bummer about the hassles, but glad you finally got some success. Believe me, if you keep tinkering with these kinds of circuits, you'll get better at it. Also, it helps a lot to try out the circuit using a prototype board before breaking out the soldering iron.

You can usually pick up spec sheets from digikey http://www.digikey.com/ . When I buy anything non-obvious, I usually print of a spec sheet and keep it in a drawer of my workshop. For things like MOSFETS, I usually keep them in a ziploc, and take a magic marker to write the important specs and pinouts on the bag.

In the case of the IRFZ30, digikey didn't include the spec sheet, but did have a link to their catalog page, which had a picture. You are correct. The soft-start diagram is wrong. I used a different MOSFET, so I never bothered looking up the IRFZ30.

With the pins down, looking at the "front" (the pretty side),
1 = gate
2 = drain
3 = source
4 (the case) = drain.

BTW, if you are making a free-floating circuit, i.e. not soldered to a board, you can make a sturdy connection by soldering to the chip's case (i.e. rather than pin 2). This makes a nice mechanical "base of operations", where you know that the pins won't break off.

Also, out of curiosity, did you use the 5-ohm jumper? Did it still get hot? I haven't gone back and tested it again (my test used a higher-wattage resistor), but would still be surprised it it got too hot to touch.

Bob S.

[redwood]

Yes, i can see the value of a prototype board!

I did use 5ohms for the jumper.

And, once again, putting a 10 ohm resistor in a circuit with the 14.8V batery and the bulb burned the paint of the resistor in a few seconds.

Thanks for the good tips.

zach

[redwood]

I just got the optronics driving lights. I'm really psyched about how solid and weather proof they seem. I replaced the thick rubber seal behind the ceramic socket with one made out of innertube in order to get the philips masterline bulb in. It's still real snug with no wiggle room, but I can actually get the lid closed all the way.

I'm working on making the sofstart circuit really small so I can immerse it in epoxy to make a strong and waterproof in-line circuit. I think I'll use a narrow prescription drug bottle lined with vaseline as my mold.

I'll be curious to test the actuall run time and dimming profile of the Li-ion battery. I'm amazed how small and light it is.

I'll keep you posted.

zach

[bigwheel]

Zach, That's a good idea about replacing the rubber seal. Getting the Masterline bulb into the optronics case is as difficult as getting my body into last summer's bluejeans.

About the Optronics fixture, I originally cut off the push-pull connectors and directly soldered the leads to my switch fixture. Then, I changed my mind, and soldered the connectors back on, so that I could quickly swap light fixtures in case of a crash or burned out bulb. I also put some heat shrink around the two leads coming out of the fixture, and stuffed it partially into the case. This probably isn't necessary, but the wires looked a little fragile.

With the soft-start circuit, I suggest an extended test run (half-hour or more) before sealing the electronics. In particular, check to make sure that the MOSFET doesn't heat up over time. I don't think it will happen (about 0.02 ohms when on), but it's better than wondering and worrying when you are out on a ride.

Finally, I loaded all of my lighting pictures onto the laptop and brought it up to the cabin this weekend. I planned to write Part-1 (Really Cheap Lights) of my HOW_TO, but never turned on the laptop. The weather was really nice and there was good snow, so we ended up going skiing both days. Hopefully, I'll get the first document written this week.

[redwood]

Zach, That's a good idea about replacing the rubber seal. Getting the Masterline bulb into the optronics case is as difficult as getting my body into last summer's bluejeans.

About the Optronics fixture, I originally cut off the push-pull connectors and directly soldered the leads to my switch fixture. Then, I changed my mind, and soldered the connectors back on, so that I could quickly swap light fixtures in case of a crash or burned out bulb. I also put some heat shrink around the two leads coming out of the fixture, and stuffed it partially into the case. This probably isn't necessary, but the wires looked a little fragile.

With the soft-start circuit, I suggest an extended test run (half-hour or more) before sealing the electronics. In particular, check to make sure that the MOSFET doesn't heat up over time. I don't think it will happen (about 0.02 ohms when on), but it's better than wondering and worrying when you are out on a ride.

Finally, I loaded all of my lighting pictures onto the laptop and brought it up to the cabin this weekend. I planned to write Part-1 (Really Cheap Lights) of my HOW_TO, but never turned on the laptop. The weather was really nice and there was good snow, so we ended up going skiing both days. Hopefully, I'll get the first document written this week.


Bob - I turned both optrronics lights into bike lights:

Left the ceramic socket in, but changes the rubber gasket think to inner tube. Put together the softstart with 5 ohm bypass. My submini toggle switch is small enough to be mounted on the light, but for the circuit to work the switch has to be behind the sofstart (found that out the hard way...oh yeah, that makes sense!) So I aranged the sofstart circuitry and the switch in a tubular conformation, encased it freeform in epoxy, and then connected that in line about 1 foot from the light. Should be OK position for bar and helmet mount i think. I shrinkwrapped all the connections, and shrikwrapped over the epoxied softstart think, so it looks reasonably professional. I also shrink-wraped over the lever of the toggle switch so it should be water resistant.

It is possible to warm up the epoxy and then pick it off the circuitry as it softens. Found that out by neccessity as well.

Another thing I discovered was that it can actually be a mental challenge to shrink wrap wires. especially when there's not much wire to work with and you must bridge sections of different diameter.

If there's one thing I've learned from this experience, it's "think first, solder later".

I'll give my light a test run, and I'll also see if I can post a picture of my setup.

zach

[bigwheel]

Zach, Be careful using a tiny on/off switch.

First off, the switch ratings are usually for AC, not DC. For reasons I won't go into here, if you are going to use an AC switch on DC, you need to use a switch rated at several times the DC current. In your case, I wouldn't use a switch rated less than 6 amps.

Second, the switch will take a lot of physical abuse. The subminatures are kind of fragile, and can't always handle the punishment.

BTW, did you try a run-time test? Your 20w masterline will draw approximately 1.9 amps. In theory, this means that a 4AH battery should last a little over 2 hours. However, you can't always trust the ratings, and some manufactures exaggerate their claims more than others. If you did a test, I'd be interested in knowing how long it ran.

NOTE: Stop your test when the light starts getting dim. If you wait for it to go dead, you can end up with a reverse charge in your weakest cell, which does a lot of damage. Also, Lithium batteries have a tendency to explode if they are misused. (Really. That's why all newer watches have a metal back. ) Hopefully, the safety circuit that came with your battery will shut it off before then.

[redwood]

Foiled Again!

Thanks for the heads up about the submini switches, Bob. One of my switches is a 10A mini; the other a 3A submini. I guess I'll use the mini until i get the other one replaced.

The batteryspace li-ion circuit protection does protect against overdischarge. Thanks for the warning though. This project has already stressed my relationship with my fiancee enough. (My light testing is generally after midnight and it's a very small apartment). If I end up needing a trip to the ER, she'll probably make good on her promise to put my bike light to good use "where the sun don't shine".

zach

[redwood]

Bob - the light ran for 2:13, at which point it switched off abruptly. My voltmeter showed no voltage coming out of the battery at that point, so i charges it for about 10 seconds, and checked again. 13.5 Volts.

The only thing that heated up was the optronic light fixture, and man that got hot! When I spat on it it boiled right off in seconds.

zach

[bigwheel]

Bob - the light ran for 2:13, at which point it switched off abruptly. My voltmeter showed no voltage coming out of the battery at that point, so i charges it for about 10 seconds, and checked again. 13.5 Volts.

The only thing that heated up was the optronic light fixture, and man that got hot! When I spat on it it boiled right off in seconds.

zach

Good, thanks for the info. Sounds like the circuit did a low-voltage shutdown. 2:13 is a good run time for a 4AH battery and 20-watt bulb.

So, the Lithium battery is a nice option -- about half the weight of NiMH, and only about twice the price. Lithiums are slightly trickier to charge, but reasonably priced chargers are available, and included in some of the packages.

If you want to get the fixture *really* hot, try a 35-watt bulb. That's what I'm running on my bars. It was the difference from 20 to 35 watts that forced me to switch from a homemade PVC fixture to the Optronics. 20 watts worked fine, but 35 watts was enough to melt the PVC after about a half-hour of use.

Glad to hear that the MOSFET didn't heat up. Last night, I did some experimenting with the soft start circuit. Without the rest of the soft start circuit, the resistor got hot after a couple seconds. However, with the soft start in place, it was okay.

I had two soft-start circuit variations that seemed interesting. One could be put "upstream" of the switch, but one didn't let the bulb go to full brightness. The other one used the MOSFET to do the "heavy lifting", so you could get away with a tiny on/off switch. However, that one took a long time for it to turn the light off. (soft-stop?)

Here is a picture of how I did my headlight mount. The connector is a 3/4 inch electrical conduit bracket, with a wing-nut and shrink-wrap to keep the bracket from scratching the bars. It also has shrink wrap on the wires.

[dave t]

So, since a lot of night riding takes place in the colder time of the year, do you think that if you could use the bars as a heatsink, there is enough heat to do double duty as a handwarmer?

[bigwheel]

So, since a lot of night riding takes place in the colder time of the year, do you think that if you could use the bars as a heatsink, there is enough heat to do double duty as a handwarmer?

Interesting idea. With the right kind of fixture, you might be able to transfer a substantial amount of heat to the bars. However, I'd guess it would dissipate into the frame a lot faster than it made it to the end of the bars, through your grips and gloves.

[bigwheel]

Well, I decided to take another crack at it and build yet another helmet light. This one turned out nice. It is built mostly of parts stolen from my last version, but has the new softstart circuit, which I was able to cram into a tiny space and silicon into the fixture. Here's the completed circuit. (note that I also used 2 10-ohm bypass resistors)

[Kosk]

Hey guys,

Been following your conversation here in the back ground for a while. I've got an ME degree and like the DIY solutions, always enjoyed EE lab and the soldering iron. Seems like this would be fun to try for next winter. Bob do you have anything resembling a how to for making the 20W PVC lamp, and a circuit diagram and part list for the slow-start switch, low-V shut off thingy?

How much does this run you guys? I've always though the night riding in the late fall, early winter would be fun, but can't see shelling out $100s for lights. I'm partial to full-moon rides, but they come infrequently.

Thanks for any info,
Pete

[bigwheel]

Hey guys,

Been following your conversation here in the back ground for a while. I've got an ME degree and like the DIY solutions, always enjoyed EE lab and the soldering iron. Seems like this would be fun to try for next winter. Bob do you have anything resembling a how to for making the 20W PVC lamp, and a circuit diagram and part list for the slow-start switch, low-V shut off thingy?

How much does this run you guys? I've always though the night riding in the late fall, early winter would be fun, but can't see shelling out $100s for lights. I'm partial to full-moon rides, but they come infrequently.

Thanks for any info,
Pete

Hey Pete,

You probably won't need an ME degree to build these lights. Most of what we do is based on what you learned in high school science classes.

Last night, I just wrote my first cut at Part-1 of a homebrew lights HOW-TO. I finished it around midnight last night, so I haven't done any clean-up on it. I plan to have 3 parts when I'm finished.
Part 1: Really cheap handlebar lights - PVC fixture and Sealed Lead-Acid Battery
Part 2: Really cheap helmet lights (will not discuss batteries or esoteric stuff)
Part 3: Better Lights - will discuss optronics cases, soft-start circuit, soldering your own battery packs, high-low beams, etc.

Again, all I have so far is a first cut at Part-1. I can probably write Part 2 in a couple evenings, but Part-3 is going to take longer.

Zach found the initial soft-start circuit, and posted the link. http://mysite.verizon.net/~tbrown59/gif/softstart.gif
I did some testing on the circuit, and made a couple minor changes. First off, the MOSFET is labelled backwards. Pin 1 = gate, Pin 2 (or the tab) = drain, Pin 3 = source. Second, the soft-start doesn't get rid of all of the surge. You can fix this by adding a 5-ohm resistor as a bypass between the source and drain. This will let the light start warming up sooner, and almost completely cut out the surge. For the 1M and 10M resistors, you can get by with 1/4-watt resistors. For the 5-ohm bypass, use at least a 1-watt resistor. It is only on for less than a second, but heats up pretty fast. (We have been using 2 10-ohm resistors in parallel)

As far as a low-voltage cutout, I have not been using one. I just look at the light output, and manually turn it off (or onto low-beam) when it starts to get dim. However, it appears that the Lithium batteries that Zach is running have a cutout built into the pack.

Let me know if you are starting to build right away, and I'll send you a draft copy of what I'm writing. Otherwise, I'm going to try to get John Lundell to carve out a place on the morc site to put technical articles.

I get the same kind of feeling using home-brew lights as I do riding a bike that I built from a pile of parts. It is also an ego boost when the others in your group complain that your light is too bright and "ruining their wilderness experience".:p

Bob S.

[Kosk]

Sweet deal, sounds good. I'll probably be interested in all of it. No hurry, the days are getting longer. I just noticed how handy it would be to have one for late in the season when daylight hours dwindle. (especially this year with the lack of snow) So I'd be aiming for next year.

What's the deal with the soft start, is that just to save the lamp from being exposed to high start up currents, yielding longer bulb life??

[redwood]

Sweet deal, sounds good. I'll probably be interested in all of it. No hurry, the days are getting longer. I just noticed how handy it would be to have one for late in the season when daylight hours dwindle. (especially this year with the lack of snow) So I'd be aiming for next year.

What's the deal with the soft start, is that just to save the lamp from being exposed to high start up currents, yielding longer bulb life??

In addition to the benefit of extended bulblife, the softstart is needed (not optional) with my Li-ion battery. This is because the battery comes with current-limiting circuitry that cuts off the power if the current gets too high as in a short circuit. When you hook a cold bulb up to a battery with this circuit protection, the cold bulb offers very little resistance and current gets too high, shutting off the light.

As far as cost, I spent roughly:
$65 - battery pack with smart charger
$10 - philips masterline MR16 bulb
$12 - two optronics driving lights(shiny steel thing pictured a few posts down)
$10 - resistors, capacitors, shrink wrap, a bit of wire, etc.
-----------------
$97.

I think it could be done more cheaply with NiMH batteries, and a PVC set up. Also factor into the cost that tinkering makes you susceptible to drinking lots of beer.

Good Luck,
zach

[bigwheel]

What's the deal with the soft start, is that just to save the lamp from being exposed to high start up currents, yielding longer bulb life??

According to what I've read, running resistance of halogen lights is 20 times the starting resistance. In practice, the initial current surge is 14x the running current. This causes two problems:

1: The startup current surge decreases the bulb life, And as the bulb gets older and the filiment gets thinner, it may exceed the current limit of what the filimant can handle. This is why much of the time a bulb dies when you first turn it on.

2: Because of the dangerous characteristics of Lithium batteries (i.e. they explode), Li-Ion battery packs often have a built-in circuit to prevent short circuits. The halogen startup current surge exceeds the current cutoff, causing the circuit to "turn off" the battery before the light turns on.

Soft start circuits are basically current limiters that let a bulb warm up slowly, so that the filiment is hot (and low resistance) before full power is applied.

[redwood]

Just got back from a midnight trail ride to test my bike lights. Kind of odd test conditions, perhaps, as the ground was snow covered and there was a full moon. But anyway, here's my comparison of my frankenlight and my NiteRider Storm HID. First of, both worked really well and did exactly what they're supposed to. Bob, I copied your bar mount and it worked well for me - stood up to lots of vigorous bunny hopping.

That said, the frankenlight was markedly brighter. I put both lights on my bar for comparison, so they would cast the same shadows. the frankenlight pierced the woods much deeper, resolving distant branches the Storm couldn't reach. For objects in range of both lights, the Frankenlight was brighter, brought out more colors, and left crisper shadows. If I shined both lights in the same place, switching off the storm made a moderate difference in overall light in the woods, while switching off the frankenlight made things seem dim and blue. If I light my eyes adjust for 15 seconds or so, the storm still put out plenty of light.

The storm seemed to have better peripheral illumination. When I actually compared the area of periphery illuminated and the brighhtness of that area, the frankenlight covered the same amont of area, but was actually brighter than the storm everywhere, and all the way out to the edge. But actually riding with the two, the storm seemed to light the corners better. I think that's because the frankenlight is so much brighter in the center that it distracts from the periphery and/or my pupils constricted in response to the bright spot, preventing me from being able to see the periphery as well.

What I noticed more than the absolute brightness of the frankenlight, was the warm yellow/white color of the light. I may sound like a fruitcake, but the frankenlight made the woods seem warm and inviting like a big bonfire, while the storm, by comparison, made things look cold and austere, as though I were exploring on the moon. Though maybe I wouldn't have noticed so much were it not for the snowcover.

[bigwheel]

That's great news, Zach. Thanks for the update.

If I remember correctly, you are running an 8 degree 20-watt Masterline. Unfortunately, the 20-watt Masterline doesn't come in a 24 degree configuration. It's either 8 or 36. (Let me know if I am wrong.) If you find that you'd like to trade some of the piercing brightness for more peripheral vision, you might want to try out the GE bulb from Home Depot. It is a 20-watt bulb, with a 15-degree beam. (about $6) Not quite as bright as the masterline, but significantly better than any of the other brands that I've tried. It also uses slightly less power than the Masterline.

If you are planning to also have a helmet light, the 8-degree Masterline is the perfect bulb. I'm currently running it on my helmet, and running a 35-watt, 24-degree Mastrline on my handlebars. It is waaaay overkill and forces me carry another 1.5 lbs of battery, but is fun to use.

BTW, Last night, I spent the evening drawing circuits and trying them out on the prototype board. I came up with a high/low beam circuit, with soft-start for both beams. It is based on a 555 timer, a MOSFET, and a bunch of resistors and capacitors. I ran a bunch of tests on it, and it seems to work well. It also lets you get by with a tiny switch, because the switch is only controlling the timer functions. The drawback is that it uses 0.01 amps when turned off, so you shouldn't leave it connected to your batteries when you are not planing to go for a ride. I'm going to do a little more tweaking on the circuit, and see how small I can make it. If successful, I'll post something and include it in part-3 of my how-to.

[redwood]

Bob - I've been thinking about the sub-mini switch on my light. i get what you say about average current AC being about a third of peak AC current or steady state DC current. I also noticed that the current rating on the sub-mini toggle is 3A 125V / 1.5A 250V. Maybe they're rating switch capacity based on power and the switch will handle 30A at 12.5V? I left the sub-mini on for a while and it didn't heat up. But it is very flimsy feeling, and I may replace it with a beefier 10A mini toggle anyway.

[bigwheel]

Bob - I've been thinking about the sub-mini switch on my light. i get what you say about average current AC being about a third of peak AC current or steady state DC current. I also noticed that the current rating on the sub-mini toggle is 3A 125V / 1.5A 250V. Maybe they're rating switch capacity based on power and the switch will handle 30A at 12.5V? I left the sub-mini on for a while and it didn't heat up. But it is very flimsy feeling, and I may replace it with a beefier 10A mini toggle anyway.

Zach, the problem is not while you are running. The main difference comes when you turn the switch OFF while under load. An AC current will cross the zero axis within 1/120th of a second, and snuff out any arc. The DC current will continue the arc, and sometimes have a small plasma trail that carries the arc for a longer time.

My understanding is that in addition to catastrophic failures, (stuck ON while burning up), the tiny arc wears out the switches a lot faster, and causes pits on the contacts.

Generally, DC switches have a faster connect/disconect, and hold the contacts wider apart when off.

[redwood]

Zach, the problem is not while you are running. The main difference comes when you turn the switch OFF while under load. An AC current will cross the zero axis within 1/120th of a second, and snuff out any arc. The DC current will continue the arc, and sometimes have a small plasma trail that carries the arc for a longer time.

My understanding is that in addition to catastrophic failures, (stuck ON while burning up), the tiny arc wears out the switches a lot faster, and causes pits on the contacts.

Generally, DC switches have a faster connect/disconect, and hold the contacts wider apart when off.

Interesting. now i know.

zach

[redwood]

I put together a helmet mount for the optronics light. I removed the "U" shaped bracket from the bottom of the light, got it red hot over a stove, and then pushed it through a rectangular scrap of that PVC I'd already heat-shaped to my helmet. Basicly looked like a huge staple going through the flat PVC from the underside. The "prongs" stick out the top, ready to accept the light. Padded the underside with foam, and hooked up some straps to go through the helmet vents. Seems real solid. A picture's worth 1000 words here, but hopefully you get the idea.

Obviously, it's a lot of fun getting metal red hot and then pushing it through plastic!:evil:

[bigwheel]

Zach, Cool idea. It's amazing what PVC will do once it gets hot.

I'm sticking with the homebrew PVC helmet setup for now. I have a tendency to thump my helmet on branches, so I need something a little more rugged. It looks a little strange, but is low-profile and fairly lightweight, and leaves me room for a switch and small circuit.

BTW, I spent all afternoon/evening yesterday with the prototype board. I finally have a decent high/low beam circuit with built-in soft-start that I think will fit into a tiny space. I tested it with 20-watt and 35-watt bulbs with voltages from 7.2-16.5, and it seems to work well without heating up. I might build it for real tonight.

[bigwheel]

In case anyone saw that they missed their chance for the nice Li-Ion packs from batteryspace.com, I see one on eBay that looks like it might be the same thing (maybe the same people).

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=22689&item=7138498760&rd=1

14.4 volts, 4000 mAH, stuffed into a water bottle
Weighs only 380 grams (half the weight of my AA helmet light pack)
(Enough to run a 20-watt light for over 2 hours)

Buy-it-now price $68.95 (with charger)

Pretty tempting...

[redwood]

In case anyone saw that they missed their chance for the nice Li-Ion packs from batteryspace.com, I see one on eBay that looks like it might be the same thing (maybe the same people).

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=22689&item=7138498760&rd=1

14.4 volts, 4000 mAH, stuffed into a water bottle
Weighs only 380 grams (half the weight of my AA helmet light pack)
(Enough to run a 20-watt light for over 2 hours)

Buy-it-now price $68.95 (with charger)

Pretty tempting...

That's a good find. I actually emailed batteryspace about that product because a couple of my frinds want that battery pack, having been impressed with mine.

Bob - those same friends are interested in your pvc helmet mount. I imagine you've got the procedure pretty well streamlined at this point. Anyway, I look forward to you putting up a DIY guide. Mainly I'm wondering why you put the pvc on the BBQ, and if or how you sealed the back of the tube.

zach

[bigwheel]

Mainly I'm wondering why you put the pvc on the BBQ, and if or how you sealed the back of the tube.

I use the BBQ as an oven to heat up the PVC so that I can re-shape it. The BBQ heats up quickly and is easy to access. Besides, my wife would have a Grand Mal Conniption if I used the kitchen oven.

I don't bother sealing my light fixtures. (I do seal the electronics with silicon, though.) We don't usually ride in the rain, as it destroys the trail. Besides, the fixture and helmet will shed the water, and it won't hurt to get a little bit of moisture inside, as it will quickly drain or evaportate.

For PVC, I use the stuff that is intended for drain extensions under the sink. It is not the fragile down-tube stuff, but the stuff that is slightly heavier, and not as brittle. They are in the same area at Home Depot, and come in lengths 6-18 inches. It weighs almost nothing.

I cut the pipe on an angle, so that the "tail" can wrap around the back of my helmet, and hold the back straps. Then, I throw it into the oven. (Note: put a piece of aluminum foil under your work.) Once it warms up, it's just like puddy to work with. Then, I squish it down on my helmet, and work it into the right shape. If you need some more adjustment, just heat it up again. Later, I add a rubber pipe connector to hold the bulb, and add the switch and electronics. Surprisingly, it has no problem with heat from a 20-watt bulb.

Here's a couple pictures of the PVC piece before I add anything. As you can see, it is fairly low-profile and rugged, and has enough room to put a switch, a small circuit and some velcoro straps.

[bigwheel]

Part 1: Really Cheap Headlights.

[bigwheel]

Part 1: Really Cheap Headlights.

Ok, so the upload didn't work. I asked JL for a place on the MORC site to store the documents. Meanwhile, send me an email if you'd like a copy. It is an 8-page PDF, which takes up about 410 kb of space.

[Kosk]

Bob, Zach,

Have either of you lookied into High Outout LED bulbs?

http://www.superbrightleds.com/MR16_specs.htm

Down the page a bit are some 6 LED HO MR16 bulbs. They are rated for 10-14VDC and draw 200mA. How does that compare to the Halogen bulbs, are they not bright enough?

I guess I'm interested in this because I have one of those Petzel LED headlamps that will run for over a hundred hours on 3 AAA batteries. I don't know how it all works out, but it seems a LED bulb arrangement would give you way more battery time?? They cost about $25 a piece though.

[bigwheel]

I'm a big fan of LEDs and believe that some day they will rule the world. I've already built quite a few LED lighting gadgets for my cabin and have been happy with them. IMO, they are already the way to go for tail lights.

However, for bike headlights, they just don't cut it (yet). As a comparison:

The brightest LED in an MR-16 fixture:
http://www.superbrightleds.com/MR16_specs.htm
uses only about 1.75 watts, and puts out 31 forward lumens.
That's about 17.7 lumens per watt - not bad.

An equivalent Halogen MR-16 fixture:
http://www.lighting-fixtures-ceiling-fans.com/store/PPF/parameters/643_231/more_info.asp
uses 20 watts, but puts out 240 forward lumens (8x the light of the LED)
However, that's 12.0 lumens per watt, which is worse than the LED.

The LED light has 30 LEDs, each with an output of 3000mcd (3.0 CP) or a total of 900CP. (NOTE: This incorrectly assumes perfect focus, and that no light spills onto the adjacent LED.) Meanwhile, the 8-degree, 20-watt Masterline (my favorite) puts out 6,500CP, or 7x the brightness.

So, the LEDs are more efficient, and have the advantage of being rugged and having an extremely long life. However, they currently just can't pack enough light into a small enough space to compete with halogen or HID.

LEDs will get better, though. The current bulbs use 3000 mcd LEDs. You can now buy 20,000 mcd LEDS, however, they currently cost about $2 each. (check eBay). Once they start putting the better LEDs into fixtures, the feasibility will be worth revisiting.

FYI, The white LED is a relatively new invention. It is actually a blue LED, that excites a phosphorescent material, which glows white.

[Kosk]

Sweet thanks for the info. Yeah after my post I found some tables comparing lumens and saw that the LED bulbs were +10X less than the Halogens. That's kinda what I was figuring, they just aren't bright enough...yet.

[bigwheel]

I haven't posted here in a day, so here's some more. This is the finished version of my current headlight. Inside of the case, it has the soft-start circuit that we discussed. It's the one that I posted the picture of. I used a smaller switch than on my other lights, rated at 10 amps. This one is destined to become my spare. (see next post)

[bigwheel]

This is the finished high/low beam switch, with built-in soft-start. It has a chopper circuit that pulses the light 240 times per second. Low-beam has a duty cycle of 57 percent, which still puts out a reasonable amount of light. I tested it with 20 and 35 watt bulbs, between 7.2 and 15.5 volts, and it seems to work fine in all cases. The thin yellow/red/brown wires go to a double-throw switch, to control off-low-high beam. Since there is hardly any current in these wires, you can get by with a tiny switch. This turned out way better than I expected, so I plan to make another helmet light, and stuff the switch inside. I'm going to do a couple stress tests, then add it to part-3 of the how-to.

[redwood]

So I have to ask: How many lights do you have Bob?

[bigwheel]

So I have to ask: How many lights do you have Bob?

Several sets, but not as many as it sounds. I usually rip apart my least favorite, and steal parts for the next one. That way, the cost of building a new one is only a couple bucks.

[bigwheel]

Tonight, I tried a long-tem burn on the new helmet light. The light was the same basic design, but had the high/low beam circuit stuffed inside, and a nice small off-low-high switch controlling the circuit.

The circuit ran flawlessly, but the PVC didn't:cryin: After about an hour with the 20-watt bulb running full-blast, I noticed that the PVC started getting mushy near the bulb. So, I had to stop the test after just over an hour to avoid ending up with a blob of plastic.

This was my first long-term test with the lightweight thin-wall PVC. The light I used last summer has gray PVC conduit rather than the lightweight (white) stuff that I'm trying now. The conduit ran flawlessly last summer, however it was probably cool enough outside to keep the PVC above the mushy temp.

So, this was definitely a bummer. In addition to losing a few hours of work, it throws a wrench into the whole idea of a lightweight PVC helmet light.

Needless to say, I'm going to have to hold off on part-2 of the how-to for now. I don't want to write a detailed description of how to build something that melts when you use it.

[bigwheel]

Don't panic, but JC whitney no longer carries the metal optronics lights.

However, I found them at a few other places, although they all have outrageous shipping costs.
http://www.motorheadtools.com/product_info.php?products_id=1306&osCsid=1ef715fd51dcb378758210034ddf038b
http://www.nationalonlinesales.com/show_Product.asp?ID=1660
http://www.mydiscounttools.com/show_Product.asp?ID=1487

[KleinCrazy]

Bob,

How about using some ype of thin wall aluminum tubing? Not Pop Can thickness, nor Bike tube thinkness but something in between. Might not be as easy to find as PVC, but should be just as formable, and more heat resistant.

Sorry, can't help with sources or such. maybe there is another type of thinwall heat resistant plastic out there also. I know I have stuff in my lab that is good up to 121C and some that is higher. Can you set up a test to determine what type of heat output your system in generating? If need be I have access to a Thermocouple that goes well into the 600's F I think.

James

[bigwheel]

Bob,

How about using some ype of thin wall aluminum tubing? Not Pop Can thickness, nor Bike tube thinkness but something in between. Might not be as easy to find as PVC, but should be just as formable, and more heat resistant.

Sorry, can't help with sources or such. maybe there is another type of thinwall heat resistant plastic out there also. I know I have stuff in my lab that is good up to 121C and some that is higher. Can you set up a test to determine what type of heat output your system in generating? If need be I have access to a Thermocouple that goes well into the 600's F I think.

James

Good idea. I was thinking the same thing, but couldn't figure out where to get the metal or how to bend it.

I know that they make heat-resistant plastic. I just don't know how to work with it or where to get it. Maybe if it is the right diameter, we could use it for the couple of inches closest to the bulb, and leave everything else the same.

My meter has a temp probe, so I'll run another test and find out how hot it gets.

Thanks.

[The Buckthorn Killer]

Good idea. I was thinking the same thing, but couldn't figure out where to get the metal or how to bend it.

"Discount Steel and Alunmum" It's on Washington/94. They have tons of stuff, and they will sell it by the foot.

[redwood]

Don't panic, but JC whitney no longer carries the metal optronics lights.

However, I found them at a few other places, although they all have outrageous shipping costs.
http://www.motorheadtools.com/product_info.php?products_id=1306&osCsid=1ef715fd51dcb378758210034ddf038b
http://www.nationalonlinesales.com/show_Product.asp?ID=1660
http://www.mydiscounttools.com/show_Product.asp?ID=1487

I found the optronics web sight

http://www.optronicsinc.com/competition.htm

and just called them directly to get my lights. They had a charming southern accent and the shipping wasn't too bad. If you are bored, ask them about the pros and cons of different types of varmint lights.

[dave t]

How about fiberglass cloth and marine epoxy?

[SuperClydesdale]

Bob,
How about using some ype of thin wall aluminum tubing?
James

Aluminum tubes?!?! You know what the %#^& you can do with aluminum tubes?!?!

[bigwheel]

Zach, Were their prices decent? I'm seeing around $11.50 + $10 shipping on the other sites. Normally, you pay a little more when dealing directly with the manufacturer.

Dave, that's an excellent idea that I hadn't even considered. Thanks:banana: I've done a ton of fiberglass work, on sailboats, kayaks, and building canoes. I already have all the cloth and chemicals. It wouldn't be very hard to build a mold, and turn out cheap custom fixtures.

Tom, is that the place AKA Gerlicks? Anyway, I might try Dave's idea first. Thanks.

Mark, Good point. All the aluminum tubing is probably being used for high-end bikes. It's a good thing that some of the lesser people are going back to third-world materials and primitive technology for their bikes.

[bigwheel]

Digging around, I came across a nice site that contains lots of info on building your own lights:

http://nordicgroup.us/s78/

On another note, I have been experimenting with various mounts on my new helmet, and unfortunately, won't be able to use my old lights with the new helmet. The old 1979/1980 vintage MSR that I used last year had a round top, where I could use the velcro straps to adjust the beam angle. Unfortunately, the new Specialized helmet has a relatively flat top, so I need a different way to adjust the beam.

So, at the moment, it looks like I'm stuck with the optronics mount, similar to what Zach built. The unfortunate part is that the new light sticks up higher and is a lot more vulnerable to a branch taking it out. The old light was held close to the helmet, and was also a lot stronger of a fixture.

With this in mind, I'm probably going to combine volumes 2 and 3 of my how-to, because they will now have similar information.

[bigwheel]

I was starting to worry about not being able to get the metal Optronics light fixtures (QH-7CC or QH-7AC). JC Whitney hasn't had them on their site for a couple months, and motorheadcity ended up cancelling my order, because they could not get them.

So, I wrote a letter to sales@optroncsinc.com, and received this response:


We still carry these lights. I am showing that JC Whitney is still purchasing them from us. We are currently out of stock on them. The cost if you purchase direct from us is $13.69 + $3.95 s/h.

Thank you,

Michelle Young
Consumer Service
Optronics, Inc.

</pre>

[bigwheel]

I happened to score a 14.8 volt, 6,000 mAH Li-Ion battery pack for $30.00 on an eBay 2nd chance offer. Not sure if the link works, but here it is:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5977409961

When I got the seller's email, I replied, asking if I could buy two more, and the seller sold me two more at the same price (no extra shipping).

Then, I asked him if I could tell my friends, and he said yes, but that he only had about 10 of them left. So, I'm not sure what kind of deal he'll give you, but $30.00 is a damn good price for this pack, and it's worth asking.

His name is Jason, and his email address is traderhill@netzero.net

Note that there is no charger, so you'll have to pick one up from batteryspace.com or somewhere. That'll cost about $30.00. I also have not tried out these batteries, but have no reason to think there is anything wrong with them.

FYI, this pack will power an over-volted 20-watt halogen (approx twice the light of a 13-watt HID) for about 3 hours.

I think I'm turning into a lightaholic.

[redwood]

I happened to score a 14.8 volt, 6,000 mAH Li-Ion battery pack for $30.00 on an eBay 2nd chance offer. Not sure if the link works, but here it is:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5977409961

When I got the seller's email, I replied, asking if I could buy two more, and the seller sold me two more at the same price (no extra shipping).

Then, I asked him if I could tell my friends, and he said yes, but that he only had about 10 of them left. So, I'm not sure what kind of deal he'll give you, but $30.00 is a damn good price for this pack, and it's worth asking.

His name is Jason, and his email address is traderhill@netzero.net

Note that there is no charger, so you'll have to pick one up from batteryspace.com or somewhere. That'll cost about $30.00. I also have not tried out these batteries, but have no reason to think there is anything wrong with them.

FYI, this pack will power an over-volted 20-watt halogen (approx twice the light of a 13-watt HID) for about 3 hours.

I think I'm turning into a lightaholic.

Hey bob - not to start our endless banter again, but that li-ion battery pack must come with some internal circuit protection from overdischarge, right?

zach

[bigwheel]

Hey bob - not to start our endless banter again, but that li-ion battery pack must come with some internal circuit protection from overdischarge, right?

zach

Zach, I don't know, but I doubt there is any circuit inside. I plan to just solder a 5-amp slow-blow fuse in line, and use it with the dimmer/softstart circuits that I built last winter. However, I'll bet you can skip the circuit, and wire it directly to your bulb if you don't mind the shortened bulb life. (I highly recommend a fuse.)

Since I only need two of them, I'm also considering cutting the third pack apart (into 3 separate 2000 mA packs), and making a couple compact, but bright flashlights, and a compact emergency spare bike light, similar to the one I used last fall&winter.

If anyone picks them up, post something. Then, I'll let you know what I find out when I do some testing. Before building anything, I'll probably also do some studying about Li-Ion behavior. I'm pretty familiar with NiCd and NiMH, but am a bit of a newbie with Li-Ion. All I know is that they can explode if you don't treat them nicely.

[bigwheel]

Hey bob - not to start our endless banter again, but that li-ion battery pack must come with some internal circuit protection from overdischarge, right?

zach

I received the battery packs today, and couldn't resist cutting the shrink wrap off of one of them to see what was inside.

The packs each have twelve Panasonic CGR18650A cells, wired as 3 sets of 4. There is a built-in protection circuit and what appears to be an over-temp fuse built in.

I also did some research on charging Li-Ion batteries, and it doesn't look like it will be difficult to build a charger, although it won't have all the fancy features of a smart charger. If anyone cares, I can post the circuit once I build it. I am new to Lithium batteries, so look for the smoke coming from the southern suburbs.