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  1. #1
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    Wonky XPG's on 7 up board

    I recently received a Cutter 7 up board and noticed that 4 of the LED's sit at a slight angle away from the MCPCB. They all sit square when viewed straight on, but looking from the side reveals four pitched up slightly on one side, I'm guessing by 3-5 degrees. The gap between board and LED's is made up of solder, they don't look like they are in fresh air.

    So...

    Is this going to affect the light direction and intensity much, through the tight 6/10deg Kathod optic?

    Will the gap reduce the heat transfer from LED to board sufficiently to be a concern?

    If this is a big problem, can I get this fixed, e.g. putting the board back into a reflow oven (no idea where yet) or is this board a write-off and return to Cutter?

    Has anyone else got a 7 up board with the LED's like this and what have you found?

  2. #2
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    Assuming there is adequate solder in the reflow joints to bridge the gaps, it likely won't have a negative impact on heat transfer. I think it will impact light output, but I don't really know if it'll be a significant amount.

    My speculation is that the impact on total light output will be minimal. The output from the LEDs is over a very large angle. So shifting that by 3-5 degrees will likely make little difference. I think the bigger issue could be the impact on the beam pattern. It could cause the beam pattern from those LEDs to be inconsistent. Worse case would be to create a dark spot in the middle.

    Can you hook it up and try it? You can use something like a thin sheet of aluminum or brass to selectively cover parts of the optic. That way you can compare the output from subsets of the LEDs. The pattern is easy to see if you shine it on a white surface.

  3. #3
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    yeah, got 2 of cutter's 7 up kits. Both have a few wonky xpgs. Works fine though and I cant notice any difference once the light is on between the wonky and straight xpgs. (running at 45ma to try and spot diff).

  4. #4
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    HI
    We did have a batch that did not bed down correctly, but still work ok optically, if you concerned, please return for a replacement
    Cheers
    WeLight

    Cutter Electronics Pty Ltd www.cutter.com.au

  5. #5
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    Thankfully all seems well on a 'white wall', albeit not at very low amps, yet. No magic smoke from any LED's either, so far so good. It is ringy at close quarters and looks like it will be a killer flood monster bar light. After a quick flash outside in the garden, I'm glad I chose a cool/neutral mix, too.

    First ride in anger against my mates' lights will probably be on Tuesday (though days are now pretty long). I might decide to get a special XP-E board, cool/neutral mix. Is that possible, Mark? (or Ben!)

  6. #6
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    Quote Originally Posted by AlisterG
    Thankfully all seems well on a 'white wall', albeit not at very low amps, yet. No magic smoke from any LED's either, so far so good. It is ringy at close quarters and looks like it will be a killer flood monster bar light. After a quick flash outside in the garden, I'm glad I chose a cool/neutral mix, too.

    First ride in anger against my mates' lights will probably be on Tuesday (though days are now pretty long). I might decide to get a special XP-E board, cool/neutral mix. Is that possible, Mark? (or Ben!)

    No problem let us know what you need.
    Cheers
    WeLight

    Cutter Electronics Pty Ltd www.cutter.com.au

  7. #7
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    First ride with the 7 up and, overall, it is bright.

    As nights are now short, this is not the best time to make absolute judgements about performance, so if you are interested, read the following with this in mind.

    The ringiness that is obvious at close quarters against a white wall is just not a problem out on the trail as it is in the very peripheral field of view when you are concentrating on the trail ahead. The centre beam - I can't really call it a spot - is broad and pretty even, as a flood should be.

    The cool/neutral mix works really well for me. Compared to this mix of tints, halogens look sickly yellow and HID's oddly blue. None of the other riders with me had their LED's on, so I can't compare them, but my Joystick has a very slight bluish/green tint and is drowned out within the 7 up's beam when in 700mA setting.

    However - you knew it was coming - the light does not have a killer punch. There is no sense that the light is overwhelming and I felt that some of the light is just along for the ride rather than really working for you. Unless you want a true flood, I think Trouties mix of XPG & E is the minimum you should consider. On run current, there is little point in running more than 1000mA. The difference is just perceptible when shining against a wall, but I could see no benefit on the trail, unless you want something to warm your hands on.

    An all XP-E cool/neutral mix board will probably be the way for me to go with this light, to improve the throw and cut down some of the peripheral waste. I'm keen to hear about those of you that went the all XP-E route.

  8. #8
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    I'd like to see it compared to something like a dual P7 with Ledil reflectors.

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