Ill just give you a quick run down on the light so you know exactly what im dealing with and to brag about its fun factor also.
Its a black SF L2 w/ stainless accents, Just looks great with the two contrasting colors. I used a AMC7135*8+MCU 2800mAh 5-Mode from KD or Illum supply as i buy from both but they sell the same exact part. I then added an XML U2 led and on the interior side i added 2x 7135's. I also beefed up the ground parts and positive spring, I need to try an Kan-28 in the tail for better amp flow.
Im getting different tailcap readings depending on the cell as i suspect internal resistance starts being an issue over 3A's.
HiMax 2600= 3.5A Panasonic unprotected 2900= 4.2A BIO IMR 1400=4.6A+
The issue is when i added the second 7135 i lost control of of the modes and just get HIGH, Which isn't the worst thing but it would be nice to have lower modes to help control heat and still use the light. And yes im done many things to get thermal issues under control as much as possible.
I have the 2nd star clockwise grounded for the 3 mode use. The 7135's were placed opposite of each other internally, The first is next to the positive lead and the second directly across from it. Ive had bad luck loosing mode control before with AK-47 drivers if i used the 7135 next to the positive lead on 1560mAH drivers. The only reason i used these specific spots was my soldering iron didn't have a good enough tip to get in such tight spaces, So i bought a new 50 watt one last night with a fine tip.
Has anyone lost modes by adding extra 7135's?
Any specific spots to piggyback the IC's that tend to cause issues?
I know the rear of the 7135 and the middle leg is ground, But does running those to the outer circle ground have any adverse affects?
Besides this issue i have just a few spots that need improved like the solder joints on the led board being too thick from my other crap iron, Ill smooth and lower those today as its causing a large gap between the LED and reflector and loosing focus and lumen's. Despite that it will over-run my 2.8 T6 lights when placed side by side and then merging the beam.
As to the U2 led i like it alot as im a cool white guy, It seems only slightly whiter than the T6 bin. Other than that its not worth $2-$3 over the T6 imo. Ive not had it outside yet to see its throw and flood output, But I need to get the reflector fixed for a better focal point.
Inside the house wall tests show that i cant tell it apart from the beam of my Sky Ray 3800, But i know its just my eyes can pick up the higher lumen's the 3800 is putting out. But they look like twins to the naked eye tho. It still cant beat the intense hot-spot of my KD C8 tho, I love that light!
(Edit) After reading the first sticky im gonna try and back the amp's down to around 4A as anything higher is just extra heat. I may start by removing the 7135 at the positive lead.