Budget thrower project

[qwertyydude]

Ok so I saw these at home depot today. It's the Husky 3 Watt LED Spotlight. I looked to see what kind of emitter it is, and lo and behold it's a Cree X-RE. So it's got some potential. Basics are it has a deep 2.5 inch reflector, a pathetically weak 400 mah 3xAA internal battery pack. It also comes with a wall wart and car adapter charger.

So I charged it up and it was weak, maybe 150 lumens or so. And it's runtime was only about 10 minutes of sun mode and another 15 minutes of moon mode I'm sure with some cycling it would go up but it's not much capacity to work with. So I take it apart and inside I find a decent board with three discreet transistors and a bunch of resistors, the led is attached to a decent looking cast metal heatsink, the reflector is plastic so hopefully my mods don't cook this.

So as far as I can tell by it's decently flat brightness, it's regulated. I then took out the cheapo battery pack and installed one made of 3 x sub-C nimh cells from a hobby battery. Along with that I also put in a quick charge jack so I can use my hobby charger to juice it up, the built in charger also remains in case I need to charge it on the go. Well while testing it I got a whopping 1.4 amp battery draw, with 3.7 volts to the emitter and 1.2 amps at the emitter that's 4.44 watts. Assuming this is a good bin maybe 75 lumens/watt at high power that equals 333 emitter lumens. Compared to my Q5 and direct drive P4, from a ceiling bounce test, this looks to be about 300 lumens otf, slightly brighter than my direct drive P4 at about 270. So it's efficient either the design or the led, seeing as it's spewing out more lumens with less watts.

The beamshots compare to my Q5 drop-in P60 module installed in my RC-M4. This is driven at .55 amps. and as you can see at a distance of 8 feet the beam is nice and narrow. I took it outside and tried to take beamshots of the throw, but it was to difficult to capture in a crowded suburban environment with not much targets, which under city lights I estimate 500 feet. Excellent thrower imo and even better since the light is only 20 bucks plus about 10 bucks in extra parts.

This is the finished project, the red connector is a Dean's plug which I added to quick charge it.

Here's the insides the sub-c cells fit very well, with only a little stuffing of some cotton cloth, not pictured, to wedge and keep the cells from rattling.

The reflector is 2.5 inches wide and has some very slight defects in the smooth finish but they don't affect anything.

Full exposure, at 8 feet the hotspot is about 4 inches wide, minor number crunching later this translates to a beam of about 1.2 degrees, this is narrow! Especially compared to the 8 degrees of the P60.

Here's a -2 ev exposure shot, there's a slight corona around the hotspot, spill is decent though not as widespread as the P60 drop in.

All in all this is my thrower of my bunch. Runtime is also better at about 2.5 hours til moon mode.

 

[jenskh]

Full exposure, at 8 feet the hotspot is about 4 inches wide, minor number crunching later this translates to a beam of about 1.2 degrees, this is narrow! Especially compared to the 8 degrees of the P60.

I think you have to measure the hotspot further away to get a good measure of the angle, especially for a big reflector.

 

[qwertyydude]

When I went outside and pointed it at a tree trunk about 200 feet away the beam's width was about 5 feet high. This translates to 1.43 degrees. I was still close and in the night you can see a pencil beam of light that just seems to go forever like a laser.

 

[UpChUcK]

Did you mod the controller board at all?

Is the emitter easy to swap out?

Looks like a new board could be easily put in. lots of room in there :thumbsup:.

Looks like this would be a fun little project . Might just try it.

 

[Calvin]

I also saw this light at home depot, and wondered about modding capabilities. I was concerned about the all plastic body ( no way to disipate the heat generated inside the case) Please let us know how it holds up. Also I was curious about the chargers that came with it. If I remember right the wall wart said 7.5 volt dc output, and the car charger did not appear to have any resistors in it ( output would be approx 12- 13.8 vdc ) maybe the charger board can accept a range in voltage. Just wondering.

 

[hyperloop]

Sweet! Nice mod. Sigh, we don't even have spotlights like these being sold in singapore

 

[qwertyydude]

The emitter is an easy swap. It's a simple star board, and it's held only by the pressure of the reflector on the heatsink. Controller board was not modified but I felt it didn't need it since it's alread so high powered. Plus it seems to also accept a wide range of input voltages from the various chargers. When it gets dark I'll try to post pics of the pencil beam, yes you can actually see the beam even in clear air.

I don't know of the heat dissipation but it probably needs a few holes drilled in the case and possibly a small 5 volt fan to blow air but that'll be for later. For now I just make sure to not use it for more than 10 minutes at a time. So far no angry blueness.

Update: Ok so it does get hot, I noticed a slight bluing so I installed a small fan and drilled some holes in the case, this is not splash proof anymore. But even with this the heat sink will get up to 140 degrees, not ideal but still better than before. I'll probably end up replacing the led with an R2 and regulator, it should be about as bright but run much cooler hear is an outdoor beamshot, sorry there are no targets but other houses here and at 11 at night I dare not shine these at other people's houses. The sky always looks like the sun has just set because of the light pollution.

Here you can see the almost perfect parallel throw.

The vent is right above the trigger, a little hard to see because it's all black, and there's another one correspondingly on the other side. You can actually feel heat venting when it's on.

The fan is glued to one half of the case so I can still split the case to possibly replace the led in the future, but I believe it'll last a while longer since I'll probably rarely use this and it remains a little cooler than before.

 

[qwertyydude]

Re: Budget thrower project 24,000 lux!

I've recently borrowed a friends lux meter and decided to measure a couple of my lights, at 1 meter, seems the standard here, my Aurora AK-P7 slightly modded gave a respectable 10,500 lux and my spotlight gave, get this, a whopping 24,000 lux! This is quite a thrower as I've always believed seeing as the size of the reflector and with my revised current reading it now reads 1.6 amps to the newly installed R2 led, probably expalains why it's so hot. I've also replaced the fan and heatsink with a more powerful one to deal with the heat. The star is glued to the heatsink using my homemade heatsink epoxy.

 

[toby_pra]

Wow looks pretty cool! :twothumbs