Hi guys,
About a year ago I bought a brand new Olight SR91 from a German shop; they had it on discount, being an older modell light.
I bought it to have it modded because the original specs (1500 Lumen & 160Kcd - my Thrunite Catapult V5 does better and is A LOT smaller)
were not that impressive, mainly due to the outdated led being used (Luminous SST90).
The driver was nice though, a very well regulated 6,5A 3V driver, and therefore well suited for a host of Cree leds.
Mods: first I removed the large batterytube holding the proprietary Olight batterypack (6*18650) with build in charger.
I don’t like proprietary batterypacks, making it impossible to change cells and use the latest and best cells.
Not to mention they are oft very pricey…….
I replaced it with the battery tube and cell holder of a Thrunite TN31, which fits nicely on the threads, making the light a lot shorter.
The semi-mechanical tailcap swit doesn’t work anymore, but I can live with that.
The big spring in the head (to make contact with the batterypack) was reversed to enable contact with the Thrunite cell carrier.
Then the led was removed and replaced with an old-fashioned dedomed XM L2, in view of the 6,5A driver.
This worked well and at high there was almost no green tintshift but……….the led wasn’t centered perfectly distorting the spot and it therefore reached
350Kcd only. :weary:
Second modd was to remove the XM L2 and replace it with a XP-L HI V3 and make sure this led was perfectly centered and focussed.
The friendly German TLF member that did this for me said it was “a hell of a lot of work” but he delivered. I’m gratefull. :partying_face:
My Olight TN31 now makes a nice 380Kcd on high (remember, the inner diameter of the reflector is only 65mm!), the spot is beautifull, the led has no
problems with the 6,5A and the light has no problems dissipating the heat, just look at those big and nicely spread cooling fins!
Yes, there are lights of similar size that do the same but……those are all factory build lights, for everyone to buy and this is a one-off.
Moreover, this combination of heavy head with lots of thick cooling fins and the XP-L HI make it a light that needs no stepdown, the head doesn’t get
hotter then 43 degrees Celsius, as my indoor test confirmed. :+1:
Outdoors it will even stay cooler.
It’s roughly the same size as my TN32 (also XP-L HI V3, max 350Kcd) but much sturdier and has better heat handling.
It’s a big light and not exactly lightweight but, unlike a lot of “modern” lights, this one will keep its top performance until the batteries are drained.
It now nicely fits in my collection with some other unique lights that are more or less in the same category:
BTU Shocker (Vinz modd) doing 402Kcd with dedomed XM L2’s
Vinz Speziallampen “Mjölnir” aespheric doing 506Kcd (with pre-collimator and dedomed XM L2 with surface treatment and strengthened bonding wires @ 7A+)
Nitecore TM36 LITE with dedomed XP G2 doing 849Kcd
Courui D01 (Djozz mod) UV thrower with thick copper pill and 400NM UV Led, taking some 5A. Watch this light doing its work at over 50 meters.
Useful? No, but a lot of fun!!!
Cheers,
Nico