Today we take a look at the cheapest of the cheap 1xAA torch, and what it takes to turn it into a respectable light. So many places make and sell variations of these that there's bound to be slight differences between, but for the most part this mod should be doable on the majority of them. The key here is that the head and tailcap are both removable. Although it would still be possible if the head wasn't removeable, that attribute does make things easier. Another point I wanted to keep was that this would only require hand tools and the total mod cost would be as cheap as possible. Read on to see if I succeeded:
Above is the 3 pack that I picked up and to the right is what one looks like after a quick teardown. The guts aren't glued in per say, but are press fit and will come out of the head with the proper amount of force. Pay particular attention to the white spacer in the above photo, for that and the reflector are the only two pieces that we'll be saving.
Since I plan on driving the new emitter with more than 50ma like the origional, a suitable heatsink will be required. A little scrounging around in various spare parts bins turned up an old brass bolt. The shaft was too thin, but with a bit of filing the head would be perfect. The easiest way I found to do this was to chuck the bolt up in a variable speed drill and then hold the file against the head while it's spinning. Just keep filing and test fitting. If the hand is steady enough, it'll look like it was cut on a lathe.
After the bolt head is reduced to the required size and the face of the head is smoothed out, place the bolt in a vice and drill two holes for the emitter wires to pass through, then cut the head off the bolt. I used a mounted emitter to help mark the location of the holes to drill:
Now separate the head of the bolt and use fine grit sandpaper on a flat surface to smooth everything up. It is especially important that the top where the emitter will sit be absolutely flat. Here's the final heatsink:
To finish up our new pill we need to modify that white spacer that was shown in the first pic. It just needs to be cut down to ~6mm in height and have the three plastic inner nubs cut off. After a little bit of sanding, the inner diameter was the perfect size for a spare driver I had lying around. I used a .8v-1.7v 3-mode driver from shiningbeam. Mode spacing is 900ma, 200ma, and 25ma with mode memory. I fit the driver into the base of the plastic ring and secured it with a few drops of superglue.
For the emitter, I've had an old Q5 gathering dust that was just pining to be used. To ensure a flush fit with the new heatsink I also sanded the emitter pcb on the same table with sandpaper to ensure a perfectly flat mating surface. A drop of artic silver and a drop of superglue is all that's needed to mount the emitter. Once that's done, I glued the driver/spacer assembly to the base and soldered on the leads. The pill turned out like this:
A few of you may be thinking - "Match you idiot....with the driver surrounded by plastic, how's it going to get it's negative contact?" Here's what I came up with for that little dilemma - A thin piece of copper soldered to the emitter then molded around the side of the pill. Here's how it turned out:
The only prep work left was a quick modification to the stock reflector. It entails trimming the bottom of it to fit the new emitter.
Before final assembly of the torch head, I sanded the inside of the head to remove the black coating pitifully trying to pass itself off as anodizing. I also added a very thin piece of copper sheet to the inside to help with heat and insure a good electrical ground. Here's the added copper sheeting created and installed:
Now the only thing left was to put everything back together. The stock lens and reflector slide in (tightly) at first, followed by the newly formed pill. Everything is press fit, with retention being provided still by that white spacer in the pill. Here's what it looks like in the head and the business end as it compares to stock.
The only thing left was to slip a fresh cell into it and enjoy the fruits of my labor. Due to the driver choice, I'm limited to alkaline, eneloop, or NiZn...even though the heatsink is more than up to the task of dealing with a 14500. Initial results were interesting. Even though the reflector was smooth, I expected a floodier, ringier beam due to how short it is. Well, there's a bit of unfortunate ringiness, but the center hotspot is quite intense. Instead of describing it, here's a side by side of modified(high mode) vs stock:
Not surprising, it blows the anemic stocker out of the water. It actually compares favorably with a romisen RC-G2 in output...just not quite as throwy (but in a much smaller package).
So, what have I ended up with after all this? A very lightweight 1AA light with respectable output, 3 modes w/memory, and a reverse clicky all wrapped up inside a compact package. The parts used for this consist of an emitter, driver, a little bit of copper foil, and one brass nut...all leftover bits and pieces from other projects.
As always, I hope you enjoyed this...and if not, just report it as spam