Shadows BL20 mod.

I’ve never posted pictures before, but soon I’ll have my son show be how to. This last project needs pictures. I bought a Shadow BL20 thinking its just a revamp of the TC-750X. And for some parts it is, it uses a slightly shorter dual head. It draws 2.35 amps at 8.4 volts for high and claims 1600 lumen. Side switch now does on/off low, medium then high with strobe by double tap. Compared to my TC-750X its a bit brighter and draws 0.45 amps more. Fins on the bottom of the head are absent and its drilled and tapped for a mounting bolt. Its end where a battery tube would go has been replaced with a threaded metal cap. Wires are soldered directly to the brass retaining ring and the pad where a spring should go. Thread pitch has also been changed to 1” by 24. Battery pack is the standard 4-18650’s in 2s2p 4400 mah capacity with propriety plugs. My mod is taking a SolarForce body tube and to cut it off at where the head sits flush on the body then thread 1” by 24. This would give me the following battery configs. 2-18350’s, 2-18500’s, 2-18650’s and 3-CR123A’s. I’m thinking the 2-18500’s for personal favorite. With the tapped head and the 1” body its weapon mountable. The body tube is going to get cut this week when I can get around to it. The battery tube switch will only serve as a battery disconnect stopping the parasitic electronic switch drain. This leaving the side electronic switch to do everything else. Pictures hopefully soon also. Originally this was going to be just a Shadow battery tube added but they changed the thread pattern and I’m too bull headed to call it quits. I really have a liking for the dual led style. Its unique and still fits flat on a belt or in a pocket, while beating most singles and some triples. Soon it’ll be a double barrel sawed off flashlight.

sounds interesting. cant wait for the pictures.

I started this little project back in September 2013 when I had a request for the brightest little firearm light. It had to be small enough to fit in a pocket. Bright enough to light up a football field. Fit using standard 1” rings or mounts. I’m a fan of the Shadow TC-750X but none of the body tubes fit 1” rings. So this is what I managed to come up with. Factory Led’s are XM-L2 T6’s running cool white.


I started off with the Shadow BL-20 bicycle light.


Removed the metal cap, bike mount and brass contact ring.


I’ve built six so far and two were soldered directly to the board with both wire eliminating the brass ring so two different tube cut styles had to be done.


Another image of the two different types received. Red O-ring on the brass ring style tubes.


Different extensions and tail caps including the new SolarForce L2D


Battery option, when using cr123a’s four are needed to get near full brightness.


Shadow TC-750X, modified Shadow BL-20, MAXToch DX21


Backside of the three lights, also note the drilled mount spot on the center light and the lack of fins giving a very flat mounting side.


Mounted top view with a shielded rear switch in 2-18350 length.


Side view

All the light modified draw 0.07 amps on low, 0.60-0.65 amps on medium, and 2.40-2.55 amps on high. Except one it runs 0.45 amps on medium and start 2.00 amps on high climbing to 2.50 amps in about 5 seconds. It does that weird high thing every time I cycle through. If I let it warm up it still does it. Current measurements are fairly consistent using 2 Kinoko 850mah 18350’s, 2 Keeppower 1700mah 18500’s or 2 Panasonic 3400mah 18650’s. This light head is so small and with the Led’s pads glued down the only modification my large fingers could do is solder springs in place of the old wire. If I could build from scratch I’d put a triple XP-G2 in one side and an XM-L2 U2 in the other to blend flood with throw. Of the six built, three were sold, one was given to my gunsmith and I kept the last two.