Originally Posted by
PlanoFuji
I doubt your including everything required in the cost of parts for that $20 light. Like most diy's your likely making assumptions that people will have the 'miscellaneous' stuff lying around. As just one example, just how much do you pay for a tube of silicon sealant. The last time I purchased a tube it was $6+. And then most parts need to be mail ordered. Such companies typically have minimum orders. They also charge shipping and possibly sales tax. None of that ever gets included in the 'cost' of the device.
The silicone was a leftover from my bathroom and kitchen chaulking. They are available at home depot. The cost was already sunk.
Mail order from Asian suppliers do not charge shipping or tax. A single cree xr-e red from dealextreme.com is $3.30 with shipping, everything is included .
If you can't find a local electronic hobby shop and have to buy everything from digikey, yeah it adds up.
Once again, from dx, or fasttech, free shipping, $7 for the cree leds, $2 for a pack of 5 optics, $4 for the driver, $3 for the cable, switch, and wires, maybe another $6 for a blinkie that's hacked up (that was actually free throwaway I found), plus miscellaneous (like silicone....). As for your doubt, you can do the shopping yourself online on fasttech or dx.com, you realized that experienced diyers don't question my estimate because they already know how much it cost (they can easily say BS if I'm wrong), whereas you, well, what I can say.
Originally Posted by
PlanoFuji
It isn't just tools that need to be included in the costs. For instance, if a project needs a single resistor, there aren't very many places that will sell just one. Many of the components and needed hardware are like that. As I said, if one is doing to learn or as a hobby then none of that matters. But if one simply wants to get a less expensive device, they are likely going to fail.
Resisters are sold in 10-20 package for a $1.
Originally Posted by
PlanoFuji
I seriously doubt your claims about superior performance, particularly as I posted in your thread; you didn't actually perform measurements of light output. And I suspect from your post you didn't perform measurements of actual power supplied to the LED's. Those LED's require much more sophisticated driving circuits to achieve 100 Lumens per watt. And the first indication is the 1000 Lumenclaim. The dyno's max at about 10W of power supplied. Your circuits are not supplying 10W of power to the LED's A fair bit of that power is being consumed by the inefficient circuit itself. Also the heatsinks your using are not likely keeping the devices as cool as they need to be to provide maximum output.
1000 lumens require me to be riding at 25km/h and up. Dynamo lights can supply more than 10w. I've ridden besides commercially available lights so I have visual clues for judgment.
Originally Posted by
PlanoFuji
Yes, many battery lights produce more output than any dyno light is capable of. The reason is simple, batteries are capable of supplying more power than any bicycle dyno is ever going to be able to match. That is even more true when misrepresenting the dyno output by only considering its output at maximum power from the dyno (~10W) which only occures at speeds of about 16-20mph and up... If someone feels the need to light up a small section of their path like daylight, they need battery lights.
No they don't need battery lights, a Supernova E3 triple can light up a bike path at 10mph, so can any light that pumps out 600 lumens at 10mph.
Originally Posted by
PlanoFuji
Heck, even the lumen claims of such lights are a farce. Like you, it is unlikely the manufacturers are actually measuring their light output. They are relying on the device data sheets, without regard to whether they are actually providing the environment those specs are reported around. In short those claims are marketing. The lux reporting by dyno lighting manufacturers is a much better yardstick. It is also much more straight forward for even a diy'er to produce. Those light meters are available for <$100 and that a test stand and a ruler, and even a diy'er can produce the data/graph of the light output and display pattern of their device. Show me one of those and I'll reconsider your claim that your device is superior to the Luxos, EDELUX, etc...
Once again, I've ridden besides commercially available lights so I have the necessary real life comparisons. And please, I'm not going to go out and buy a light meter to satisfy your ego when I know my light outshines my magicshine, and magicshine outshines the Luxos, Edelux. I've ridden besides an edelux at speed and I know how bright it is, I've yet to ride besides a Luxos but if the visual account from people who have 700 lumen lights are true, then my experience speaks for itself (you can disagree all you want, I don't care).
Originally Posted by
PlanoFuji
1) Reliable
2) Well designed from a safety perspective
3) Reliable
4) Efficient (I really don't want to waste any more of my effort than I need to)
5) Easily mounted securely in the proper locations.
6) Reliable
And those DIY's that have gone commerical have produced products that were much better implemented than their DIY prototypes.
Check over at mtbr.com (which I'm guessing you haven't), their commercial products are identical to their prototypes, and every components (drivers, leds, optics) they buy are commercially to you and I. The housings for "commercial" looking products can be purchased as well, like the example below.
http://www.nicobaumgartner.ch/blog/?p=198
Everything on this light is a diy, the person didn't do anything machining, just soldering. I can build the same headlight by buying all the parts, (it cost around a $100 or less (including shipping) depending on the configuration you want, and it beats anything $100 on the market (other than chinese lights and flashlights). That light is 2 times smaller than your Luxos and 2 times brighter (depending on drivers), power by 3 cree xp-g, you made a point about overheating, but you can buy drivers with thermal dimming protection.
Battery light though, the best bang for your buck is still the chinese lights, no comparison. As for your preference to German law lights, German laws suck so I like my dynamo lights brighter than what's offered commercially (with a beam that's wider and throw farther). I built my latest dynamo setup for 60km/h+ downhills mountain road rides (and it might rain) so I want all the lights I can reasonably get.