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The twin XM-L Marwi conversion lives and is posted here.
That link includes links to the Dyno conversion of low beam light posted here last year as a battery only light here. The first link also includes pics of Version 2 of the helmet light and a wall shot of its improved separation beam.
The mods to Version 2 were not posted before. It now has an XP-E R3 replacing the dedomed XP-G R5 and a B2Fex and a new single lens holder instead of three separate ones. I also allowed wide angle light from one XP-G to miss the bottom of the lens barrel to be used as side marker light with an amber hood. At the risk of redundancy here it is again with the hood:
By brianmcb at 2011-03-21
That idea worked out very well.
The XP-E adds about 0.4 watts of heat compared to the XP-G it replaced. In a <8 square inch housing, that is just enough extra on top of about 9 Watts of heat @ 1 amp to be of concern even with air flow. So I improved thermal path to the body while I was at it. It will not triggger 70 C with ambient of about 7 C and a 5 km wind riding at about the same speed. I will see if I can lower that cut off temp at higher ambients.
Now that the XM-L is available on 10 mm MCPCB, the logical way to three projected die sizes for a stacked triple beam is to START with three different sized dies and the lenses can be in the same plane which makes things much easier to construct. AND I drop more heat output than the XP-E adds. Yes, the XP-G and XM-L will be underdriven and I'd only get an inconsequential 50 lumens more from the XM-L compared to the XP-G it replaces, but as the helmet light is approaching a car beam brightness on the road, at 100 + feet and very useable aimed twice as far, that would not concern me overmuch. CREE may come out with a replacement for the XP-E that will handle 1.5 A, and I will be ready! A three LED light with different sizes of dies is an irresistable idea in this light.
So heat monitoring, beamshots, and videos and bike riding are next. And then an XM-L swap-in after I record what I have now so we can compare.:thumbsup:
That link includes links to the Dyno conversion of low beam light posted here last year as a battery only light here. The first link also includes pics of Version 2 of the helmet light and a wall shot of its improved separation beam.
The mods to Version 2 were not posted before. It now has an XP-E R3 replacing the dedomed XP-G R5 and a B2Fex and a new single lens holder instead of three separate ones. I also allowed wide angle light from one XP-G to miss the bottom of the lens barrel to be used as side marker light with an amber hood. At the risk of redundancy here it is again with the hood:

By brianmcb at 2011-03-21
That idea worked out very well.
The XP-E adds about 0.4 watts of heat compared to the XP-G it replaced. In a <8 square inch housing, that is just enough extra on top of about 9 Watts of heat @ 1 amp to be of concern even with air flow. So I improved thermal path to the body while I was at it. It will not triggger 70 C with ambient of about 7 C and a 5 km wind riding at about the same speed. I will see if I can lower that cut off temp at higher ambients.
Now that the XM-L is available on 10 mm MCPCB, the logical way to three projected die sizes for a stacked triple beam is to START with three different sized dies and the lenses can be in the same plane which makes things much easier to construct. AND I drop more heat output than the XP-E adds. Yes, the XP-G and XM-L will be underdriven and I'd only get an inconsequential 50 lumens more from the XM-L compared to the XP-G it replaces, but as the helmet light is approaching a car beam brightness on the road, at 100 + feet and very useable aimed twice as far, that would not concern me overmuch. CREE may come out with a replacement for the XP-E that will handle 1.5 A, and I will be ready! A three LED light with different sizes of dies is an irresistable idea in this light.
So heat monitoring, beamshots, and videos and bike riding are next. And then an XM-L swap-in after I record what I have now so we can compare.:thumbsup: