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  1. #1
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    Another Regina project

    Just got housings in today!





  2. #2
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    Very nice! Where did you get these made? If I remember correctly, these are the housings which use watch glass and a O ring for a very tight fit.

    What are you plans for these housings? Please tell us more about your build plans.

  3. #3
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    Quote Originally Posted by fujio001
    What are you plans for these housings? Please tell us more about your build plans.
    What he said!

  4. #4
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    I had these made by a shop where I used to work. The plan is to build a double barrel with a custom helmet mount for the light heads made of aluminum/carbon fiber combination, where the Maxflex will be located. A remote switch with a built in stat led located on the edge of a helmet. So the setup will be 2xXPG R5 @1300mA driven by 2 18650 3000mAh via Maxflex.
    Hope to finish this build by the end of the week and take it on a trail.

  5. #5
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    Very nice little housings and 2 will make an excelent helmet light

    one small detail I dont know if you have thought about

    2 XPG around 6.6 VF maybe a little more @ 1300 ma

    2 18650 li ions = 7.4/8.2 volts

    Mr Maxflex will not like that as your battery voltage is higher than the leds .

    unless you are going to wire the Batteries in parallel .

    better would be 3 cells and a Bflex

  6. #6
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    I'm already running two XPG's on 7.2V NiMH via Maxflex @1300mA. They are a bit overdriven with fully charged battery (8V) but get in regulation pretty quick. Been using this setup for about 6 months by now, and still no magic smoke from anywhere, although I had to set Mr. Maxflex to 70degC to avoid cutoffs. On the other hand 3 cells are one more than two to carry on a helmet and Bflex is hard to get these days, so if it works fine, I'll just stick to this setup. Cooling down Maxflex won't be an issue since it will be installed in the footpod of the light heads.

  7. #7
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    I'll second Trouties concern.

    Keep in mind that your Li-Ions fresh off the charger could be as high as 8.4V. IMO you will be running right at, if not over, the magic smoke edge. You could always draw down the cells to 4.0V using a 5ohm 5watt resistor after charging.

    You could run a 2 cell pack on a bFlex. The only drawback is the light will fall out out regulation near the end of the run. All that does is result in a gradual dimming of the light. Not ideal, but IMO a better solution than overdriving the LEDs with the maxFlex. Too bad bFlex is out of stock.
    Last edited by Vancbiker; 08-03-2010 at 11:22 AM.

  8. #8
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    Why not wire the cells in parallel? Then using the maxflex would be on the safe side....

    Never heared though that the maxflex is working propperly with input voltage is higher than output votlage...

  9. #9
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    Quote Originally Posted by Whitedog1
    Why not wire the cells in parallel? Then using the maxflex would be on the safe side....

    Never heared though that the maxflex is working propperly with input voltage is higher than output votlage...
    The maxflex will direct drive the LEDs until the battery voltage drops enough. It does pass through a Schottky diode and the inductor so might see a 1V drop which should help somewhat(ie 2A through the LEDs instead of 3A).

    Sample 18650 discharge curve: Knock 1/2V off for each cell and thats your LED voltage, current here.
    I dont think you'll ever get into full regulation. You could throw a diode or resistor in the LED string to up the load voltage and gain regulation.
    DIY LED Bike Lights:
    A few Dynamo builds and some Small battery lights

  10. #10
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    Bits and pieces

    Carbon fiber helmet mount out of mold after some cutting and rough grinding



    Pretty much how everything will be bolted together



    Working light with an XPG@800mA, no lenses

  11. #11
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    Very nice incorporation of carbon fiber into your design!

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