Results 1 to 10 of 10
  1. #1
    mtbr member
    Reputation:
    Join Date
    Sep 2010
    Posts
    16

    Ledil Laura, OK without plastic mount?

    Hello

    I have a couple of Ledil Laura's that I want to fit into a 20mm Hammond box. With the white housing/mounts on they don't fit inside the box without modifying the box, but If I remove the white plastic mount/housing they rest nicely in the box with the flange of the lens outside the box, which I can work with.

    Do the lenses require this white plastic mount for anything more than just providing a mounting for the lens? Will I affect the light output if I remove it? The inside of the box is black anodised but I could line the area around the lenses with tin foil or something.

    cheers

  2. #2
    mtbr member
    Reputation:
    Join Date
    May 2005
    Posts
    2,307
    You can go without the holder. It is important though to pay attention the alignment of the LED to the optic. That is the holders' primary purpose.

  3. #3
    mtbr member
    Reputation: piesoup's Avatar
    Join Date
    Feb 2009
    Posts
    448
    The white holder provides alignment for the lens and LED, that is clear. But the alignment is set up for the XP series.
    Van, have you noticed any difference in beam with the holder on or off? With it off, the optic sits flush with the MPCB. With the holder, the optic sits slightly raised.

    Is there any difference?


  4. #4
    mtbr member
    Reputation:
    Join Date
    May 2005
    Posts
    2,307
    I based my comment on my experience with the Ledil CMC optic. It uses a holder that looks identical to the Laura. In my project I machined the pocket for the LED and optic to hold the optic in the same position to the LED as the holder does. In my experience there can be a lot of loss in not having good alignment.

  5. #5
    mtbr member
    Reputation: piesoup's Avatar
    Join Date
    Feb 2009
    Posts
    448
    Thanks! I will keep the holders as I have included them in the measurements when drawing my my light.
    I just thought having the optic sit tight over the LED dome, it would have gathered more of the emitter's light to send down the trail. I measured the difference in height, 0.7mm. Then I measured the height of the dome from the MPCB, and guess what, 0.7mm! So even though you cant see it, the holder does hold the optic in EXACTLY the right position!

  6. #6
    mtbr member
    Reputation: troutie-mtb's Avatar
    Join Date
    Sep 2007
    Posts
    3,052
    no holders for me just ledges in the housing hold the optic just touching the led base
    I made a cockup on an earlier light which held the laura one mm higher and the beam was worse I couldnt work out why 2 supposed identical lights had vastly different beams untill I went back and checked all the measurements .

  7. #7
    mtbr member
    Reputation:
    Join Date
    Sep 2010
    Posts
    16
    troutie was that with an xpg or an xm-l? I'm using XPGs, so could cut out the bottom of the holder and still use it if the light quality is better with it in place, but perhaps it is better with the optic without the base of the holder if you found it better with just the optic?

  8. #8
    mtbr member
    Reputation:
    Join Date
    May 2005
    Posts
    2,307
    Optics have a design focal point. If the position of the emissive element of the LED varies much from that you'll not get the beam that you should.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Nov 2006
    Posts
    377
    Troutie, to understand what you are saying....The beam for an xml will suffer if the laura lens, with or without the holder, is raised as little as 1mm off the base of the star? I'm afraid in using my double sided tape I may have raised the holder off the star enough for the beam to suffer. I don't have the ability to machining so would it be best to glue the holder directly to the star to get the most from the beam?

  10. #10
    mtbr member
    Reputation: mattthemuppet's Avatar
    Join Date
    Jul 2004
    Posts
    2,301
    well, see how thick the base of the holder is, then make sure the bottom of the bare optic is that far off the star. Simple

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •