MrNaz
Enlightened
I've already modded my Princeton Tec Miniwave LED once. I removed the Maxbright LEDs and replaced them with SSC P4s from DX. That was successful, and yielded more light, however the light was a slightly unpleasant tint of green, and I was still not happy, because, well, I just wasn't. So I decided that the Miniwave would undergo a second, more major operation.
It is powered by 4x C-cell batteries, I was originally intending to replace them with LiIon C-cell batteries. However, charging them would be a pain, and I'd lose my ability to use cheap alkalines if I was in a bind. Thus, sticking with a 4.8V voltage source seemed the best thing to do.
I wanted to replace the 3 emitters altogether this time, with 4 Cree XRE R2-WGs and Cree optics. I'm a fan of this combo; great light output, nice tint and good beam pattern for diving.
I could have gone parallel and direct drive with a resistor, but that wasn't extreme enough. Also, I don't like light output decreasing with battery discharge. So eventually I settled on using 4 independent single chip AMC7135 boards each powering a single LED at 350mA. The battery pack voltage would always be in the range of regulation for these boards, meaning that I would get great light output, very constant over the battery discharge cycle.
I tested one emitter on a small heat spreader to ensure that the heat output of an XR-E at 350mA was not too high for the puny attempt at heat management that Princeton have made in the Miniwave's head assembly. It seemed fine, but I'd only know for sure by testing it in place.
So, it was time to build. Here's what happened:
I can't wait to dive with my newly made over light! My Miniwave was already usually the brightest light on dive days, and now it's much brighter, with far better optics.
The Miniwave is a popular torch, I can't wait to run into another dive who has one :nana:
I hope that was useful to someone, let me know what you think guys
P.S., Yes everyone, I have a fetish for epoxies.
It is powered by 4x C-cell batteries, I was originally intending to replace them with LiIon C-cell batteries. However, charging them would be a pain, and I'd lose my ability to use cheap alkalines if I was in a bind. Thus, sticking with a 4.8V voltage source seemed the best thing to do.
I wanted to replace the 3 emitters altogether this time, with 4 Cree XRE R2-WGs and Cree optics. I'm a fan of this combo; great light output, nice tint and good beam pattern for diving.
I could have gone parallel and direct drive with a resistor, but that wasn't extreme enough. Also, I don't like light output decreasing with battery discharge. So eventually I settled on using 4 independent single chip AMC7135 boards each powering a single LED at 350mA. The battery pack voltage would always be in the range of regulation for these boards, meaning that I would get great light output, very constant over the battery discharge cycle.
I tested one emitter on a small heat spreader to ensure that the heat output of an XR-E at 350mA was not too high for the puny attempt at heat management that Princeton have made in the Miniwave's head assembly. It seemed fine, but I'd only know for sure by testing it in place.
So, it was time to build. Here's what happened:
Here is the original assembly taken out of the housing. There is no cosmetic difference to an original one, as the only change at this stage was the changing of the Maxbrights for the P4s.
Once disassembled, you can see the various components of the assembly. Ignore the empty tube of epoxy in the foreground Note the emitter cup on the right.
Here are the emitters, about to be mounted in the metal cup that doubles as a heat spreader. The white paste is Arctic Alumina thermal epoxy. And no, it's not a good idea to stop what you're doing to take photos while your epoxy is in a working state.
The emitters, once they have been mounted in the cup, and the optics placed on them.
I removed the optics, so I could wire the emitters up. Here's a shot of the wired emitters, with the optics and buck boards behind. To the left you can see the old emitter array, looking forlorn like a factory worker who just got sacked.
Wiring the emitters was a challenge, there wasn't a huge amount of space in the head cavity, nowhere near as much as I though there'd be. So I had to keep the wire lengths to a minimum, which posed a huge challenge when soldering. Eventually, after two minor burns on my fingers, I used a third hand device and tweezers to get into the fine bits and keep my hands at a safe distance from the soldering iron.
The fully reassembled head. The original head was held together with screws, now occluded by the emitters. So I held it on with a few small dabs of epoxy which should hold it but still allow me to break it apart, should I need to. Time for testing!
I tested it with my benchtop power supply. At 4.8V it drew 1.35A, constant right down to 4.0V. 10 minutes of burn time at 4.5V didn't seem to heat the assembly up even to the point where it was uncomfortable to touch. Woo hoo! :thumbsup:
Back in the dive light and ready to log some bottom time!
Here's the beam pattern. As you can see, I haven't aligned the optics extremely carefully, I'll do that and then epoxy them in place. The beam pattern is what I expected from these optics, nice and smooth hotspot with spill falling off dramatically.
Once disassembled, you can see the various components of the assembly. Ignore the empty tube of epoxy in the foreground
Note the emitter cup on the right.
Here are the emitters, about to be mounted in the metal cup that doubles as a heat spreader. The white paste is Arctic Alumina thermal epoxy. And no, it's not a good idea to stop what you're doing to take photos while your epoxy is in a working state.
The emitters, once they have been mounted in the cup, and the optics placed on them.
I removed the optics, so I could wire the emitters up. Here's a shot of the wired emitters, with the optics and buck boards behind. To the left you can see the old emitter array, looking forlorn like a factory worker who just got sacked.
Wiring the emitters was a challenge, there wasn't a huge amount of space in the head cavity, nowhere near as much as I though there'd be. So I had to keep the wire lengths to a minimum, which posed a huge challenge when soldering. Eventually, after two minor burns on my fingers, I used a third hand device and tweezers to get into the fine bits and keep my hands at a safe distance from the soldering iron.
The fully reassembled head. The original head was held together with screws, now occluded by the emitters. So I held it on with a few small dabs of epoxy which should hold it but still allow me to break it apart, should I need to. Time for testing!
I tested it with my benchtop power supply. At 4.8V it drew 1.35A, constant right down to 4.0V. 10 minutes of burn time at 4.5V didn't seem to heat the assembly up even to the point where it was uncomfortable to touch. Woo hoo! :thumbsup:
Back in the dive light and ready to log some bottom time!
Here's the beam pattern. As you can see, I haven't aligned the optics extremely carefully, I'll do that and then epoxy them in place. The beam pattern is what I expected from these optics, nice and smooth hotspot with spill falling off dramatically.
I can't wait to dive with my newly made over light! My Miniwave was already usually the brightest light on dive days, and now it's much brighter, with far better optics.
The Miniwave is a popular torch, I can't wait to run into another dive who has one :nana:
I hope that was useful to someone, let me know what you think guys
P.S., Yes everyone, I have a fetish for epoxies.
