Ok, here’s the finsihed light. It weighs 7.5 pounds (3.4 kg) with the batteries. It balances perfectly at the handle and feels much lighter than 20,000 lumens. Tactile switch is at the top end of the handle. You can see the vent holes for the forced air cooling. Shown with a Sky Ray King cowering in its’ shadow:
And a picture of the LED array in the reflector (before I cleaned up all the finger prints). Temperature sensor is under that grey glob of thermal epoxy.
Beamshot against a very light beige wall. What isn’t obvious is the wall is over 10 feet wide and the light was around 4 feet from it. It was pretty much fully illuminated. The camera makes it look like there was some variation towards the edges. The beam is around 120 degrees wide with a small hotspot. The thing has almost NO throw, all flood… flood of biblical proportions. Enough flood to make Noah despair…
Getting ground based images of the beam of this thing is rather hard. The beam is over 120 degrees wide. It hits the ground near your feet and the foreground gets rather overexposed. Here is a double wide soccer field:
Ok, let’s try something a bit more vertical… how about a five story bank building? Without the light, the thing pretty much photographed as black. How far away was the camera? Try across the street… oh, woe is Noah…
For some strange reason, that streetlight is not on… I could have sworn that it was… J)
Cast of characters:
Materials:
Bridgelux C9000 array: $55
Mikasa pasta bowl (and two others): $75
Custom driver: $25
Batteries: free from a RC pilot friend… a bit worn out ($135 new)
Wire and connectors: $5
Phenolic tube: $10
1/4” aircraft plywood: $3
Nuts, bolts, washers, standoffs: $5
Diamond paste: $1 (out of a $10 syringe)
Carbon fiber cloth: $10
Epoxy: $5 (out of around $80 cans)
High Density Epoxy Filler: $1
Epoxy squeege: $1
Foam brushes: $3
Sandpaper: $3
Paint and primer: $20
Acetone: $5
Vinegar: $5
Lye: $1
Tools:
Screwdriver
Nut driver
Coping saw
Wire bush
Automatic center punch
Drill and bits (3mm, #6 screw, 1/2”)
Soldering iron (used a butane one to minimize use of power tools)
Ruler, marker, compass
Coda:
This is a rather useless light unless you want to light up the side of a building/tall tree/canyon or light a playing field/worksite from above. The beam is SOOOO wide, most light is wasted on your feet and the sky. It needs a much more reasonable reflector. It will probably be redone with a commercial copper CPU heatsink and reflector like in: 15,000 Lumen Bridgelux C9000 Light Engine