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  1. #1
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    "brim"(?) length?

    I am unable to find what I want searching....for some reason I can't remember what you are all calling the brim/lip/cap on a road bar light that cuts off the beam on top of a housing. Have I described this well enough, probably brain fart on my part.
    I am getting ready to cut a housing for a bar light for commuting and wanted an upper cutoff for the beam and wondered how long the 'brim' should be to be effective.
    Thanks,
    Andy

  2. #2
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    I don't think you will find a fixed value. It will depend on your combo of emitter and optic or reflector.

  3. #3
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    For this build it will be 2 xml's w/ reginas. I was thinking of having a 1/4" lip to cut off the beam.

  4. #4
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    For a road light I think you will want a longer lip than 1/4" to cut down on glare to oncoming traffic. The road light I built for a friend has a 1/2" and it seems to work OK. Not ideal like a true cut-off, but better than nothing. The aim of the light will also affect the glare factor.

    Some of the DIY builds have had hoods as deep as 2" if I recall correctly. Some glue a piece of mirror to the underside to reflect the light downward better.

  5. #5
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    I need one of you machine-endowed guys to make some screw in hoods that will screw into the Easy2LED housing - all of mins have at least 4-5mm of threads left once the optic glass is screwed in.

  6. #6
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    Quote Originally Posted by Andy13 View Post
    ....... and wondered how long the 'brim' should be to be effective. Thanks, Andy
    If this is about controlling the spill of the beam rather than alter the main part of the beam, I found it took quite a fair sized hood to do this on my 2 x XPG/Regina battery and dynamo lights. The farther down the road you want to point the main part of the beam and the more the spill from your optics/reflectors then the longer the hood needs to be.

    I can only show you what I ended up with for my twin (high/dip) 2 x XPG/Regina lights ... actually I did cut it down by 25% (must take new photo of this), but angled it down slightly in relation to the main light body.

    The photo shows the original hood on the "dip" beam for on-road use, I don't use a hood on the "high" (main) beam, the second hood (also cut down a bit) ended up on my dynamo light. You can see the angle between the "high" beam and the "dip" in the 2nd photo, the high beam is set to put the top of the bright centre of the beam way down the road. They work very effectively.




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