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MUFC - Champions!!!
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Discussion Starter · #1 ·
Hi Im Ben from Manchester in the UK... firstly let me say OMG some of the DIY builds on here are amazing... well done guys...

basically Im after as much advise as possible with my plan to build a decent light for some offroad night riding and commuting (when I have to)

Im going to be getting an enclosure from maplins

but need to know if the rest of my list is ok...

so far Ive got
2 x cree R2 https://www.dealextreme.com/details.dx/sku.15943
or 2 of these https://www.ledsupply.com/creexre-w100.php
1000ma buckpuck driver https://www.ledsupply.com/03023-d-e-1000.php
On/Off toggle switch
Dimmer Switch

Im not sure on what to power this lot with

Any advise/ help would be really appreciated :thumbsup: :thumbsup: :thumbsup:
 

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Lets RIDE!
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Get the R2s if you don't mind the wait for DX shipping :rolleyes: They should be noticeably brighter than the P4. ( I don't know how long shipping takes from the states to UK....It would be quick for me....LED Supply is about 40 miles from here :)

I have that same driver....works great, fairly idiot-proof (as long as you don't cross up the (+) and (-) leads).

The BuckPucks need 2v over the voltage of your LEDs, so: 3.7 + 3.7 + 2 = 9.4v minimum battery voltage. (that's a worst case calculation...newer R2s are reported to have a lower Vf). I'd go with a 12v pack.

JZ
 

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Hi Riggsy, are those Hammond enclosures? If they are, you can easily fit 3 LED's into this one:

http://www.hammondmfg.com/pdf/1455B802.pdf

I am actually in the process of trying to cram 4 Cree R2's into one, thanks to an idea I stole from johnmyster99 :D

Do you have a battery already that you are planning to use? If so, that will determine the driver you will need (boost such as the blue shark or buck such as the buckpuck). Since the simplest way to connect the LED's is in series, you can figure how many volts you will need to drive them using (number of LED's) x 3.7V. If your battery is less, then in general you need a boost driver (though make sure to read up on boost drivers since they cannot take a battery which is close to or over the combined voltage needed to drive the LED's). A buck driver is simpler since with these you just get a battery that has a voltage higher than the combined voltage needed to drive the LEDs (plus a couple volts for the driver) and it will be happy.

As for the type of LED's to get, it depends on how much hacking you want to do to the stars they are mounted to and the tint you prefer. Right now Dealextreme only caries the Cree R2's on the bigger 19.7mm board, but if you go with the Q5's which are a small step down in efficiency, you can get them on a 16mm or 14mm board. The tint is also different on the Q5's (cool) vs the R2's (which have a greenish tint). If DX was your only source I would go with the Q5's since the difference in efficiency is not that great, especially since they are gonna get overdriven most likely anyway. If you want the R2's in a different tint, you can get them at Cutter, but they will cost more (note everything on their site is priced in Australian Dollars). One caveat though, I put an order in with Cutter several weeks ago for a couple buckpucks, some Cree R2's and some Polymer Optics, but they have yet to show, so Cutter seems slower than even DX.

If you go with the same Hammond case as I linked above the biggest problem will be with the optics since you only have a couple choices to fit the 15.25mm inside height of the case - polymer optics and Carlco 10mm square optics which I think johnmyster99 is using for his build. The only place I know of to get the polymer optics however is Cutter, though others have found places that sell them in quantity. I like the polymer optics in my triple of a similar design and am using their 6 degree for a spot and 25 degree for a flood.

If you go with a taller case you will have many more options in optics and reflectors.

You will not need both a switch and a pot with the buckpuck (or the blue shark) - a pot alone will do the job alone since when you turn the knob all the way to one side it will shut it off. For a buckpuck, a 4.7k or 5k linear taper pot will work. You can also just use a switch and resistors to control the values without a pot (this is a good way to go for simplicity sake when riding, and it may be cheaper).

Good luck with your build!
 

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JimZinVT said:
Get the R2s if you don't mind the wait for DX shipping :rolleyes: They should be noticeably brighter than the P4. ( I don't know how long shipping takes from the states to UK....It would be quick for me....LED Supply is about 40 miles from here :)

I have that same driver....works great, fairly idiot-proof (as long as you don't cross up the (+) and (-) leads).

The BuckPucks need 2v over the voltage of your LEDs, so: 3.7 + 3.7 + 2 = 9.4v minimum battery voltage. (that's a worst case calculation...newer R2s are reported to have a lower Vf). I'd go with a 12v pack.

JZ
The link to LED Supply shows Q4's, not P4's. It's no R2, but better than P4 by quite a bit.
 

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Fuzz541 said:
The link to LED Supply shows Q4's, not P4's. It's no R2, but better than P4 by quite a bit.
Doh! I really shouldn't stay up so late...my mind gets fuzzy (or, rather, fuzzier :rolleyes: )

Another thought: LED Supply sells the wired buckpuck with a dimmer pot prewired, so you don't have to source your own. One more step toward idiotproofness. I went with the one you linked above....I like the simplicity of a hi>lo>off switch while riding, plus it gives me one more place to screw up the wiring!

JZ
 

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MUFC - Champions!!!
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Discussion Starter · #8 ·

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Hi Riggsy, you should check out Neilt's build, it may provide a good reference for your build. If you are doing a double, I would suggest using one of the thicker Hammond cases since it will probably look more balanced and you will have many more optics choices.

If you do go with the thicker case, I can recommend Brumm over at CPF who carries various optics including the Ledil Square optics. He is also very helpful if you need help with the selection, but a good place to start is with the Ledil Square CRS / Cree XR-E optics.
 

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Lets RIDE!
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riggsy said:
ok so far Ive got
2 x Cree Q4 XR-E Star http://www.ledsupply.com/creexre-w100.php
Wired Buckpuck 1000ma with dimmer pot thing http://www.ledsupply.com/03023-d-e-1000p.php

power wise I was going to run both LEDs from a 6x AA battery holder with 6 x 2700mah AA batteries - will this be ok???
You're going to need a minimum of 9.4 volts using a buck driver (assuming the Vf for the Q4 is 3.7v, like the Q5): Add the Vf of the LEDs, then add 2v for the BuckPuck = 9.4v. Six rechargeable AAs only gets you 7.2v. Eight x AA gets you to 9.6v, but it would be better to have more voltage....when it runs down a bit and drops below 9.4v the BuckPuck will no longer be regulating the current. That's why I was recommending a 12v pack or better....gives you more runtime before dropping too low. batteryspace.com has some decent prices on battery packs, but not sure on shipping time and price to UK. There's a guy on the forum here from the UK who builds battery packs....anyone remember who?

Don't forget your optics when you place your order. LED Supply has these and these to fit the Crees, depending on the size of your case. Lots of other options out there too.

JZ
 

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Lets RIDE!
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HuffyPuffy said:
Awesome, Ledsupply is great, I wish they would carry more stuff so I could order everything from them :D
+1....Quick ship and great service. I ordered a couple of the 190 lumen red/orange Luxeon IIIs from them, one turned out to be bad, and they replaced it right off.

I do wish they'd carry more recent Cree bins though. Q4 is the brightest they have available on their website. I had to endure Deal Extreme's shipping to get some Q5s or R2s. Been meaning to e- or call them to see if they have anything new that's not yet on the site.

JZ
 
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