catching up on old knowledge: LuxIII to SSC

[kosPap]

well I have a question regarding this mod...

especially regarding die height when the 2 LEDs are star mounted...

is it the same

so far I have exchanged the LuxIII in a Petxzl that i think the beam changed, a Huntlight where I raised the SC LED with the SS 0.030 discs, and an Anglelux where Zi trimmed the reflector legs to a beam of my liking but making no measurements...

so...what happens when you exchange LuxIII to SSC when the reflector is not movable?

 

[Justin Case]

The die height difference should be close enough to 0.03". Here is my reasoning.

Not quite LED/star vs LED/star, but I recently built some LED Turbo Towers to fit into SureFire TurboHeads and I had to figure out LED focus height as well. For tower #1, I had a tower that was claimed to be optimized for Seoul P4 focus. I had assembled that tower a while ago and it seemed to give an excellent beam with an intense hot spot. So my working assumption is that the claimed focus height was optimum. The SSC P4 was a bare emitter, not on any sort of star.

Tower #2 used a different tower design with a slightly different tower height. Plus, I wanted to use an XP-G that was on a nominally 1mm thick (turned out to be closer to 0.85mm), 8mm diam MCPCB. I used my calipers to estimate the XP-G die height relative to the bottom face of the MCPCB (assuming that the die was at the same height as the top of the LED case).

Referencing the case height from the XP-G datasheet, it was clear that MCPCB thickness plus datasheet case height didn't equal the overall height I measured with my calipers. The difference was most likely the thickness of the reflow solder layer. The MCPCB thicknesses for various XP-Gs seemed consistent.

I measured several XP-Gs on 8mm MCPCBs and there was a small variation of about +/-0.02mm. My calipers actually measure in inches, out to four decimal places, and the +/-0.02mm figure above is based on a conversion from inches to mm for the overall LED die height. 0.02mm is 0.0008 inches, which is far less than the standard 0.03" die height difference between a Lux and a Seoul P4.

Assuming that your MCPCB thicknesses are consistent for the two stars, I would then assume that the die height difference is still 0.03 inches.

 

[kosPap]

Assuming that your MCPCB thicknesses are consistent for the two stars, I would then assume that the die height difference is still 0.03 inches.

indeed....but what complicastes maters for me is that the SSC seems a bit raised on the MCPCB....it is either the reflow material, the electrical contact that is there or....bad point is that I have no star mounted at hand, and the mod will be made by another guy actually.

My plan now involves reading old theads....see what is ahppeing when there can be no compensation applied.

I had one more point to make but i forgot it...I am fresh from the dentist and a bit quezzy....