Exactly - I like this light. I like and want an adjustable, and based on the other review on this thread, this is a pretty good light for this category. Find me another light, same size, same brightness, same flood to throw range, with 3 modes, memory and a warmer tint for $25 and I’ll definitely buy one, if its under $50 odds are I would still buy it.
I’ve seen some lights sold where you can select the modes and tint, but I haven’t found it for a zoomie. If there’s a location to order as desired, or already standard in the specs I want, please point em out.
I like everyting about the light except the modes and tint (and the tint really is not a big deal to me). Why wouldn’t I tweak it if that would make it pratically perfect for me? I’ve just never modded or had anyone mod a light, so the cost for that is an unknown to me. If it would cost 3 x the value of the light to get some one to mod it, then I’ll probably live with it as is.
I’d swap emitters and drivers for you for free but my soldering skills aren’t at the point where I’m comfortable doing work for others yet. Besides, I think JohnnyMac already volunteered in post #3.
It’s a nice zoomie, based on my limited experience. However, I’ve mostly stopped using zoomies unless I specifically need one for some reason. Usually, this means I’m trying to take a photo of something and want a nice, even splash of light. The lack of a hotspot is nice for some things. It can be nice for pointing things out to other people. Or, if I want to spotlight something with no spill, a zoomie is nice for that too. Sometimes having spill would be annoying or would interfere with seeing something far way. Or if there’s a lot of fog or smoke in the air, it’s fun to wave a zoomie around like a light saber.
So, I generally don’t take mine out of the house unless I’m anticipating a specific need for a zoomie. I find spot+spill reflector-based lights more useful for EDC purposes.
The calipers I ordered showed up today, so I started taking apart my Ultrafire 838 zoomie.
What I found inside is both better and worse than expected. The good news is that the emitter star is labelled as “CREE XML-U2”. The bad news is that the pill is hollow, so only the edges of the star are resting on the pill… and it’s only connected by the small amount of force exerted by the reflector holding the star in place. Take out the reflector, and the star is just floating there.
I tried to take it apart further, but the pill is really, really stuck. It’s a long/deep pill with the driver at the far (deep) end. So, lots of hollow space between the driver and the emitter.
So. While it would be easy to swap out the emitter, it looks like a royal pain to change the driver. Also, given that the emitter star is mostly just touching air (with light pill contact at the edges), it seems likely to cook itself on high with 18650 batteries.
Is there any easy way to improve heat transfer? I’m not sure if I should, for example, stuff aluminum or copper foil into the hollow space and press the star against it as firmly as possible… or if there is a better way. That seems like it would at least improve the heat transfer a little, but not as much as a proper heat sink with solid contact across a large area.
If you want to take the driver out of the pill, this technique works well for me with Sipik SK58 and 68 pills: place two pots side-by-side. Put boiling water in one, and put cold water filled with ice cubes in the other. Using needle-nosed pliers to hold the pill… dip it in one pot, then let it sit for 20 seconds or so, then rapidly move it to the other pot. Repeat. Thermal shock will cause the aluminum in the pill to expand and contract and the driver will pop right out on its own.
To improve heat transfer in a hollow pill, I took 3 pieces of thin aluminum. Cut them with heavy duty shears into disks approximately the same diameter as the inside of the pill. Cut notches in each one (or drill holes) for the emitter wires. Then laminated them together and glued them into the pill with arctic alumina thermal epoxy to serve as a heatsink. The back of the star then rests against this new heatsink. Not sure how much it helps, but it should be better than nothing.
