Join Date: Mar 2008
Location: East Florida
Bikes: '66 Raleigh Superbe, 80 Nishiki Maxima, 07 Gary Fisher Utopia, 09 Surly LHT
I had the same issue. I used a copper coupling to house #11621 (same drop in with a Q5 emitter). It is too big for 1" copper tubing, and too small for the coupling, but... a piece of cpvc pipe (3/4", I think) fits snug inside the coupling, and insulates the drop-in from the copper. Mine is sealed in silicone behind a lexan plug(easily cut with a hole saw and a drill press). I soldered the power wires direct to the drop-in, and buried them in silicone as well. I have yet to notice any heat build up issues. Maybe I am shortening the life of the emitter, but no issues that I can see yet.
I strapped 3 of these together, and angled them out slightly to get a wider patch of light. I power it with 8 nimh AA's--lights are parallel, batteries in series. It goes a bit over 2 hours, and provides a very useful light. When I get a camera, I will post a bike light vs. car light shot.