I was very excited when I modded my first G2 with an SW0 SSC and the SKU7880 board. It was bright... somewhere between the Medium and High settings of a Fenix L2D-CE.
However, I wanted more. So here it is - the pursuit of the "pocket searchlight".
Shopping list:
1. Romisen RC-G2 (naturally) from DX
2. Cree R2-bin XR-E emitter (bare) WG bin (CPF marketplace)
3. SKU7880 board from DX
4. MCB650 Cree mounting PCB from the sandwich shoppe.
Tools/Supplies:
1. Soldering Iron (15W radioshack type)
2. WBT 4% silver-bearing solder (partsexpress)
3. Arctic Silver 5 Thermal compound (newegg)
4. Dremel w. various bits (Home Depot)
5. Curved forceps
6. Straight forceps
7. Curved Hemostat
8. Needle-nose pliers
I will write up the exact procedure a little later, but without further ado, the beamshots.
RC-G2 vs Fenix L2D-CE LOW
RC-G2 vs. Fenix L2D-CE (medium)
RC-G2 vs. Fenix L2D-CE (high)
RC-G2 vs. Fenix L2D-CE (turbo)
Sorry about the color, but I haven't fully figured out how to use the camera. In reality, the color of the R2 WG bin is much closer to that seen in the 2nd pic - very CREAMY white... with a slight tinge of yellow... very warm and pleasant.
In ceiling bounce tests, the light seems to unbelievably tie the Fenix L2D-CE P4 on Turbo, which means it's putting out at least 135 lumens at the emitter, on just a single AA.
As you can see from the pics (and if my camera could underexpose more, I'd do it), the hotspot of the RC-G2 is significantly brighter than the L2D-CE on Turbo, and this is even more readily apparent in real life. This is amazing, given that my L2D-CE has a smooth reflector. A quick look outdoors puts this light in the Fenix T1 category, in terms of throw. When I get my T1 and the SSC-modded RC-G2 from my friend (borrowed it for hiking), I'll do an outdoors comparison.
For those who want to do this mod, here's a quick overview:
0. Remove the pill, by rotating it out using needle-nose pliers or curved forceps.
1. Unsolder the driver (I used unsoldering braid)
2. Unsolder the P2 LED
3. Remove the pill (I used a small flat-head screwdriver)
4. Remove the star and the LED (I ripped it out using pliers)
5. Use a rotary tool to enlarge the hole at the back of the pill as much as possible (take off ~0.4mm)
6. Use a rotary tool to shave about 0.8mm from every edge of the 7880 driver
7. Prepare the emitter by flowing a little bit (<0.5 mm^3) of solder onto the terminals
8. Prepare the PCB star by flowing ~2 mm^3 of solder onto the back of the emitter terminals. Place thermal compound on the back of the emitter.
9. Cut out holes for the wires in the MCB. I used a dremel with a cutoff tip, and simply cut straight lines into the MCB 180 degrees from one another.
10. Place the emitter exactly into the correct position on the PCB, then carefully allow the solder to reflow, while pushing gently down on the emitter. I clamped it down using hemostats, which allowed the bottom of the emitter to come down onto the MCB base.
11. Place the driver in its proper position, and thread the wires through the holes in the pill. Solder them to the MCB solder points.
12. Test the light engine to make sure the LED lights up, and test battery draw. Assuming 600mA to the LED, and an 80% efficiency of the driver, you should be getting 2-2.5A draw from the battery.
13. Solder the driver negative rings to the pill (I prefer doing it in at least 4 points, for lower resistance, and a stronger bond.
14. Place thermal adhesive under the MCB, then use forceps to lower the MCB onto the compound, then press and twist. Take care to ensure that all the slack wire goes into the pill, and the underside of the MCB contacts the pill fully.
15. Also add thermal adhesive around the places in the driver rim where it wasn't soldered. This will permanently mount the driver, and ensure that it won't come loose from shock if the light falls.
16. Screw the pill into the light.
17. Place the isolation plastic ring onto the LED, the screw the head down, so that it secures the LED assembly and let the epoxy cure for 20-30 minutes.
18. Insert battery and enjoy!
However, I wanted more. So here it is - the pursuit of the "pocket searchlight".
Shopping list:
1. Romisen RC-G2 (naturally) from DX
2. Cree R2-bin XR-E emitter (bare) WG bin (CPF marketplace)
3. SKU7880 board from DX
4. MCB650 Cree mounting PCB from the sandwich shoppe.
Tools/Supplies:
1. Soldering Iron (15W radioshack type)
2. WBT 4% silver-bearing solder (partsexpress)
3. Arctic Silver 5 Thermal compound (newegg)
4. Dremel w. various bits (Home Depot)
5. Curved forceps
6. Straight forceps
7. Curved Hemostat
8. Needle-nose pliers
I will write up the exact procedure a little later, but without further ado, the beamshots.
RC-G2 vs Fenix L2D-CE LOW
RC-G2 vs. Fenix L2D-CE (medium)
RC-G2 vs. Fenix L2D-CE (high)
RC-G2 vs. Fenix L2D-CE (turbo)
Sorry about the color, but I haven't fully figured out how to use the camera. In reality, the color of the R2 WG bin is much closer to that seen in the 2nd pic - very CREAMY white... with a slight tinge of yellow... very warm and pleasant.
In ceiling bounce tests, the light seems to unbelievably tie the Fenix L2D-CE P4 on Turbo, which means it's putting out at least 135 lumens at the emitter, on just a single AA.
As you can see from the pics (and if my camera could underexpose more, I'd do it), the hotspot of the RC-G2 is significantly brighter than the L2D-CE on Turbo, and this is even more readily apparent in real life. This is amazing, given that my L2D-CE has a smooth reflector. A quick look outdoors puts this light in the Fenix T1 category, in terms of throw. When I get my T1 and the SSC-modded RC-G2 from my friend (borrowed it for hiking), I'll do an outdoors comparison.
For those who want to do this mod, here's a quick overview:
0. Remove the pill, by rotating it out using needle-nose pliers or curved forceps.
1. Unsolder the driver (I used unsoldering braid)
2. Unsolder the P2 LED
3. Remove the pill (I used a small flat-head screwdriver)
4. Remove the star and the LED (I ripped it out using pliers)
5. Use a rotary tool to enlarge the hole at the back of the pill as much as possible (take off ~0.4mm)
6. Use a rotary tool to shave about 0.8mm from every edge of the 7880 driver
7. Prepare the emitter by flowing a little bit (<0.5 mm^3) of solder onto the terminals
8. Prepare the PCB star by flowing ~2 mm^3 of solder onto the back of the emitter terminals. Place thermal compound on the back of the emitter.
9. Cut out holes for the wires in the MCB. I used a dremel with a cutoff tip, and simply cut straight lines into the MCB 180 degrees from one another.
10. Place the emitter exactly into the correct position on the PCB, then carefully allow the solder to reflow, while pushing gently down on the emitter. I clamped it down using hemostats, which allowed the bottom of the emitter to come down onto the MCB base.
11. Place the driver in its proper position, and thread the wires through the holes in the pill. Solder them to the MCB solder points.
12. Test the light engine to make sure the LED lights up, and test battery draw. Assuming 600mA to the LED, and an 80% efficiency of the driver, you should be getting 2-2.5A draw from the battery.
13. Solder the driver negative rings to the pill (I prefer doing it in at least 4 points, for lower resistance, and a stronger bond.
14. Place thermal adhesive under the MCB, then use forceps to lower the MCB onto the compound, then press and twist. Take care to ensure that all the slack wire goes into the pill, and the underside of the MCB contacts the pill fully.
15. Also add thermal adhesive around the places in the driver rim where it wasn't soldered. This will permanently mount the driver, and ensure that it won't come loose from shock if the light falls.
16. Screw the pill into the light.
17. Place the isolation plastic ring onto the LED, the screw the head down, so that it secures the LED assembly and let the epoxy cure for 20-30 minutes.
18. Insert battery and enjoy!
Last edited:
