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  1. #1
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    Double Regina build with XPG's

    Woke up early this morning so I knocked up a double Regina helmet light.

    This would have to be the easiest build I have done. 1 piece body, simple mount held on with 3M industrial hook lock tape and a bflex. The machining took no time at all and assembly was nice and easy. As the mount is alloy it is easy to bend it to get the lights pointing in the right direction to suit the helmet it is being used on or to spread the beams.

    The light at present is powered by a 14.8v battery pack as I don't have anything smaller a the moment. Preferably I am going to make one more housing and turn it into a triple driven from a 11.1 pack and the bflex. The momentary switch is mounted to the side of the helmet so very easy to adjust brightness levels at present being 350, 700,1000mA. It would be nice to have a maximum of 1200mA however to get that little more light.

    At present the bflex is mounted inside some heat shrink till i make a small puck to house it in. Will do that Tomorrow I suppose.

    All up is weighs around 70g with the bflex so a perfect helmet light.

    Beam wise I need to borrow a camera that I can set exposure etc. One thing I would say however is there is a slight darkening in the center of teh spot. Has anyone else seen this. I assume the regina is meant to sit flush on the led board.

    All in all very happy with this build. I'm going to make some more and anodize them. In my excitement with this light I forgot all anodizing till it was assembled. With the 7 up on the bars and this on the helmet will be like someone turned on the sun


  2. #2
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    nice

    how did you close the reginas?

  3. #3
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    Quote Originally Posted by bravellir
    nice

    how did you close the reginas?
    A circle of 2mm polycarbonate pressed into the housing to keep it simple.

  4. #4
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    I notice that the light tubes are slightly off set. I would think this would reduce throw but make a wider over all beam. Was this by design? Oh, BTW, nice build.

  5. #5
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    Quote Originally Posted by Cat-man-do
    I notice that the light tubes are slightly off set. I would think this would reduce throw but make a wider over all beam. Was this by design? Oh, BTW, nice build.
    The mount can be bent to have both light parallel or like they are in the picture. They started out parallel but i didn't like the beam so I spread them out slightly.

    As they are at present the beams cross over each other by about 50% in the centre at a distance of about 20 meters giving a slightly wider beam than a direct spot. If i make the 3 up I will make the outside 2 lights points inwards to cross over the middle beam. This should achieve a wide beam but still achieve the brighter center, in theory anyway.

    I will say one thing however and that is this is a very bright light with fantastic throw. I have a paddock behind me and I can light up the houses 150m away. Simply amazing for 2 little xpg's
    Last edited by brad72; 10-31-2010 at 04:16 AM.

  6. #6
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    This is not a critique on your light at all, but mine. I have a single XP-G lamp, similar to yours but with alot less surface area.
    I haven't turned it on as I am waiting for a driver. How hot do yours get? Have you gone overkill on your fins or just being cautious?

    Loving the simplicity of yours!!

  7. #7
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    The light housings are 50mm long so only about 25mm of finned length. On the kitchen table they do begin to heat up slowly but outside there is very little heat present. On my summer night rides the outside temp will be somewhere around 25c-30c so I didn't want to take any chances of getting too hot, plus I want to be able to drive the leds at 1200mA so i want to remove the heat without any worry.

    Also figured that 75g for the entire light the little extra finned area won't hurt.

    As for the simplicity it was nice to make a complete light in a morning. No frustrations of fiddly machining. This build was really enjoyable.

  8. #8
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    brad, you say that you have a slight darkening in the centre of the spot.

    Seems odd as I do not have this effect with the Reginas mounted flush to the Led board and the very centre is the brightest part of the beam. My front plate is however well and truly squashing the reflectors onto the LEDs.

  9. #9
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    Quote Originally Posted by yetibetty
    brad, you say that you have a slight darkening in the centre of the spot.

    Seems odd as I do not have this effect with the Reginas mounted flush to the Led board and the very centre is the brightest part of the beam. My front plate is however well and truly squashing the reflectors onto the LEDs.
    The beam has 3 distinct areas. The outside ring, intermediate ring and center spot. The slight darkening in the center has a yellow green tinge to it, like the led colour when the light is off. Maybe i'm just seeing things, wouldn't be the first time. Probably just because the light is so bright bouncing off a light coloured wall.

    The reflectors are centered to the leds and hard against the board so probably nothing wrong

    She certainly is a bright little bugger though. The more I shine it outside the more impressed I am with it. The poor horses and hares in the paddock behind us can't work out whats going on
    Last edited by brad72; 10-31-2010 at 05:50 AM.

  10. #10
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    I've being experimenting with a similar setup, but using a 1000mA buck, and the amount of light and the throw are indeed amazing. Was surprised because the double xpg/regina's somehow appear to have a much better beam that a single xpg/regina.

    I can confirm yetibetty, I have the Reginas mounted flush to the Led board and the very centre is the brightest part of the beam.

    About temp, I'm using half a Hammond box, and indoors it gets hot fast but outside moving, it just gets warm.

    I test it outside just once ( dam flu ) and using a MS battery, after about 2h20m the voltage was still 7.45v, so I’m guessing I should get a nice runtime before it goes out of regulation.
    It makes and amazing helmet light.

    How did you cut the polycarbonate with such a precision?

  11. #11
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    First time I saw the Bflex in the PCB, I thought it was too pretty to be hid away. That lasted until my kludgy soldering. I suppose its a look only light geeks would like. Similar to a plexiglass hood on your hotrod.

  12. #12
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    Quote Originally Posted by bravellir

    How did you cut the polycarbonate with such a precision?
    I use a rotary table and my mill to cut them out. Perfect circles

    As for the darker tint in the center of the beam I am unsure if it is just my eyes as 2 x led/optic units wouldn't do the same thing.

  13. #13
    A waste of time it is is
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    Arhh, I hate you Brad, "Woke up early this morning so I knocked up a double Regina helmet light."

    I've been working on a triple for about a fortnight now and still am about a week from finishing it, and even then it will look down right amateur hour next to that.

    But very nice build none the less

  14. #14
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    Quote Originally Posted by emu26
    Arhh, I hate you Brad, "Woke up early this morning so I knocked up a double Regina helmet light.":
    Sorry Emu, was just one of those mornings where the planets aligned and everything fell into place.

    I took the kids to work with me to give mum a break so the only problem I had was the "we're hungry, what can we eat" speel every 20 minutes.

    Oh yeah and the kids think I made the light for their bike's. A 4 and 8 year old would be spoilt with such bright lights. They should have to start with a tyre drive dynamo light like we had to
    Last edited by brad72; 11-01-2010 at 02:01 AM.

  15. #15
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    Well i have an observation.

    The bflex as you can see from the pictures is temporarily mounted in some heatshrink till I get around to machining a small alloy housing for it. When the light is driven @ 1A from a 14.8c pack the bflex heats up, and after a short while dims the light with temp sensing cutoff set at 60c.

    Now I was under the impression that the bflex didn't need to be thermally potted or it just the heat shrink causing it to overheat. My other builds have had the center temp sensing IC chip touching the housing so did this remove the heat from the bflex?

    Any thoughts would be greatly appreciated

  16. #16
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    I didn't think it needed potting either. all of my earlier builds have the bflex wrapped in either electrical tape or heat shrink and shoved inside the housing without any dimming. Mind you, they are earlier versions that didn't have the temp sensing.

    You might also find that it has something to do with the difference in battery fv and LED fv. From memory the Taskled drivers work more efficiently when the two are close. Try an 11.1 v battery if you have one spare

    Sorry mate, can't be any more help than that.

  17. #17
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    Thanks for the suggestion Emu. I tried a 11.1v pack and it did last about 5 x longer till thermal dimming took over. Perhaps a 7.4v pack would be better?

  18. #18
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    brad, I think emu is correct and the bFlex is working hard to buck down your 14.8v battery when the LEDs vf is only around 6.3v. As we all know the battery will be more like 16v when full and that is quite a bit of work for the bflex.

    Having said that my twin runs fine from 18.5v without problems normally I use 11.1v but I used the light to crawl around in the loft for an hour last week to find a leak in the roof and grabbed my 18.5v as it was close to hand.

    George says that the bFlex shouldn't be potted and I found out that they don't like static, maybe the heatshrink is causing static or something.

  19. #19
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    Thank for that guys. I'll make up the alloy case for it and see if it improves things. I'll also make up a 7.4v pack to test it as well

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