A few quick questions that I need help with (so I can proceed with the build!!)

[rdhfreethought]

Hello all,

My first post here so bear with me:

I tore down my 8 year old Cygolite Lead acid dual head halogen, after the bulbs finally blew. I am building a dual LED. I purchased:
- Cree XR-E Q5 Emitter on Premium Star (228LM at 1A) x 2 emitters
- Buckpuck 700mA, wired
- Arctic Silver
- old Cygolite and original 10 degree/20 degree reflector and internals (rewired for series)

My questions are as follows:
1. For series configuration, will each emitter see 700mA (since there is no free meal, does voltage double?)
2. The reason I am slightly underdriving the Q5 is due to my worries of overheating. It should still put out @ "700mA: 171.2~182.4lm" which will likely be plenty. Unfortunately, the case for the Cygolite is plastic. I understand the heatsinking is a 'black art' to some extent, but what would be the best way to go about doing this. Would simply attaching the emitter star to a piece of aluminum (inside!!) the case be sufficient? How about a heat pipe to a heatsink?
3. How do I go about attaching the emitter+star to the heat sink itself, is Arctic silver a good thermal paste for this purpose?

thanks for the help!

 

[aljsk8]

Hi

arctic silver is good for attaching but unless you are also mechanically fixing stars (screws) - it can work loose

you can get arctic alumina (sp) which is a thermal ADHESIVE - so a permanent bond

and you can get arctic silver in an adhesive format that does the same job

as far as im aware you will need to wire the leds in parallel - otherwise the current will be split into 3 - you better wait for someone else to confirm this tho

Alex