Alright! After much tinkering I have managed to put together something resembling a flashlight :twothumbs
It's a bit late so I will try not going into excruciating detail. This was my first build so it's definitely not perfect.
Of my original parts list, here's what changed:
- Driver: 0.55 inch (13.97mm) diameter driver from SS. Custom blank with 1A constant current
- Emitter: Nichia 219C 4000K reflowed onto Sinkpad XP 10mm MCPCB
- Switch: Terralux TCS1 Tail Cap Switch I found online. Might go back to the Kroll though
- Power: 1x 14500 Nitecore NL1485 OR 2x AA NiMH OR 2x Alkaline AA
So basically my original idea of stuffing a XHP50.2 with two 14500 was shear heat-generated madness.
So without further ado here is the build. I tried taking some pics but I'm a bit of a noobie on this so..follow any of this at your own risk.
Some Kapton tape after soldering the 26AWG silicone wire to the pads:
Seeing how it fits:
Closed circuit test (no open circuit protection so this is how I tested the electronics). Also I put some black RTV silicone gasket maker in there before final installation but don't have any pictures of that:
How it looks inside the tube. You can see my really terrible sanding job to get the copper heatsink flush for proper fit of the MCPCB:
Here it is soldered in place after snipping the silicone wires. Of note is that the silicone wires were a pretty tight fit when screwing in place. I applied a bit of SuperLube to the copper threads though I don't know if that was a great idea or not:
Here is the front. I probably need to trim the reflector height a bit. Yazkaz mentioned this but I haven't gotten around to it yet. There is a small gasket in there as well to provide insulation between the silicone wires and reflector:
Not too bad:
Nitecore 14500 and dummy AA:
Both beam shots below were taken on my Samsung Galaxy S8 at 1/30s and ISO 200 from approximately 3 meters away against the top corner of my ceiling where it meets a brick wall. I also set the white balance manually but don't remember to what temp.
Also just realized I don't have a before MagLite shot. I think I might have a stock one in working condition lying around somewhere I might edit this later as a point of reference.
MagLite Mini Mod below. I still may be modifying the reflector to smooth this out a bit (the pattern there is likely the gasket sitting too far from the LED). I also have some d-c-fix I picked up in case I wanted to add that on so I might do that:
And a SST-20 4000K Emisar D4 at highest regulated for comparison:
I haven't done any multi-meter measurements yet so I don't know exactly what it's drawing. But if the Sandwich Shoppe driver delivers the 1A constant current as it claims we should be seeing ~353 lumens as Texas_Ace reports here
According to ToyKeeper here
the D4 with Nichia 219C at highest regulated output should be at 150 lumens. Even though mine is the SST-20 4000K model they output similarly and I can't find a ramping lumens table for the SST-20 so that's the best I've got so far.
Also tested with Alkaline and NiMH AAs and there's no perceptible change in brightness. Which makes sense with this buck/boost driver.
Fun fact I learned along the way:
There is a reasonable variance in diameter in the AA spec. Wikipedia lists the diameter at "13.5–14.5 mm". Though all the batteries and tubes fit within this spec, there's just so much slop. Inner diameters on MagLite bodies from the 90s are narrower than modern ones and won't fit anything but Alkalines and unprotected Li-Ions. Since the SS driver doesn't support LVP, I really wanted to use a protected cell.
For anyone looking into a project like this, the Nitecore NL1485 has so far been the only protected cell I've had fit the tube without trouble. The KeepPower 14500 cell could be coaxed in but it was a tight fit and takes some shaking to get it out.
I measured the following with my calipers (narrowest to widest):
|Alkaline AA (Energizer)||14.01mm|
|Efest IMR 14500 650mAh||14.135mm|
|90s incandescent MagLite tube||14.19mm|
|Nitecore NL1485 14500 850mAh||14.198mm|
|IKEA Ladda NiMH||14.32mm|
|Modern Xenon MagLite tube||14.4mm|
|KeepPower (EVVA) 14500 800mAH||14.4mm|
And that's it. It's late and I'm turning in. Looking forward to some questions, feedback, and advice. Cheers!