Man, you guys have been super helpful. Thanks so much.
I’m definitely liking the 612 light that 4Wheeler linked to. I’m going to go with that. I picked up a couple of Nichia LEDs from Illumination Supply and ordered the rest of what I think I’ll need from Fasttech. Let me know if I’m missing anything.
Also, I had a question about what you look for when choosing a driver? I see some have a different number of modes, but it there something else I should keep in mind the next time I tackle another project using a different LED?
Looks like a good decision on your parts to me. I have a bunch of P60-type lights. I wish I could go back in time and get that host light instead.
The only other part you may or may not need is a spring for the battery side of the driver. I usually just solder a small piece of solid copper wire. If your light changes mode when shook, then you will need a spring to keep constant battery contact. You may get a driver spring with the host.
Sounds like you are set up for soldering. If you don’t already have some, you will need rosen-core solder wire for electrical components. You can get it at Home Depot and other places if you don’t have it. Acid-core solder will likely damage your pcb’s.
Do you have any of those cheap 1 or 3 watt led’s. If you do, you can practice reflowing on one of those first. There are several threads on reflowing here. Acquiring the skill to reflow will open up all kinds of possibilities for you.
I find it easiest to reflow on my flat-top stove (ceramic or glass?). I use parchment paper and then aluminum over the heating element. The paper helps me slid the emitter and base smoothly on to and off of the heat. If the parchment paper starts to burn, you have the temp too high. The parchment paper is usually slightly burnt after I reflow leds. The temp needed is close to the max of the paper. The aluminum foil helps capture the heat of the element and deliver it to the star. You need to add just a little solder to the bases you purchased. Not much though. You want as thin a layer of solder between the emitter and base.
This is my driver of choice in single cell lights. I add or remove amc7135 to get the current I desire. The Atiny13a chip on it can be easily flashed with my own program to get the modes I want. The equipment to do so is cheap, but there is a lot of computer stuff to learn to do it.
Wishing you all the best on your build. Please ask questions as needed. The folks here are great and will be happy to help. If you feel like it. Post a build thread. People like me love reading those (learn a lot from them) and it may help future new modders.
Thanks for the tips. I’ve only reflowed surface mount LEDs once or twice before on some car related stuff, so could use more practice. I’ll test out the stove top method and see if I can get a hang of that. Now that I have a bunch of extra 20mm stars heading my way, I can do plenty of test runs…haha.
Stovetop reflow isn’t that hard once you figure out the right temperature and the right amount of solder to put on the pads. The second one can be a little tricky if you use plain old solder instead of reflow solder paste. It’s really easy to use too much solder which can seriously diminish thermal performance and can also result in the LED being mounted unevenly.
Other than that, the next most difficult part is just handling the bare emitters. Bare Nichia 219 are tiny and the ceramic substrate is very thin. They can be hard to grip securely by the sides even with a good pair of tweezers. You have to be careful with them because one slip and the domes can be scratched or sheared off pretty easily.
You sound like you have some good transferable skills. Please excuse me if I say stuff you already know.
I didn’t notice the 20mm star issue. Pre-made 16mm stars will be much easier, but you can cut and file the 20mm stars down to 16mm. I bought those same stars and had to cut all of them down because I hate wasting money. Make sure you at least rough file the bottoms of the stars to get them flat. Some people recommend lapping with very high grit sandpaper to get max contact. I generally don’t do that.
The wire contact pads will be cut through some. So you will need to test for continuity while in the pill to make sure you have no short. The driver shouldn’t be touching the pill during test because that will give you a false positive.
Yeah, I was thinking the same. I’ll just grind them down if Illumination Supply isn’t able to add the 16mm stars to my order in time.
Do you mean the edges of the star shouldn’t be touching the pill after I cut them down? Or is there something I also have to look out for on the driver?
I picked up some lower temp paste and already have some flux. Is the Qlite driver good because of the extra modes? I’m just realizing what all those star shaped solder pads on the PCB are for now. I thought it was just for looks at first…haha.
The edge of the underlying aluminum base can touch the pill, but the layer that you solder too can’t. If you look closely, you can see the underlying copper trace that connects the emitter’s contacts to the solder pads. The stars you purchased have 4 layers (top to bottom):
Top insulation layer. It has cut outs for the emitter connections and for solder the wires from your driver. You can actually lightly scrape off if you need to solder in a different spot.
Copper traces. There are 3. One for negative and one for positive feed. The middle one going under the center of the emitter helps spread the heat from the emitter. The positive and negative traces are what you don’t want to touch the pill directly.
Insulating layer. This is usually solid. Some copper stars have a cut out under the center of the emitter to improve thermal path.
Base. Aluminum in the case of the ones you have above.
I haven’t tried a Qlite driver yet. My understanding is that they are basically Nanjg 105c drivers. So I buy the cheaper ones at FT. I would like to know what makes them worth more though. Lots of people recommend them.
Good idea to make sure. Yeah, if the driver is touching the pill, it will make it look like a short when you touch one probe to a solder pad on the star and the other probe to the pill. the driver can be connected via the wires, but can not be physically touching the pill when you test for shorts.
Not sure if that was clear. Let me know if it isn’t.
I wanted to post a quick update (and maybe some photos later.) I successfully swapped out the LEDs on all four of the NEW-612 lights I ordered. They don’t mention any branding on Fasttech, but the ones I received had “Torch Light” etched on one side. I’ve have been testing them out for a few days now, and I’m very pleased. I find the tint/CRI of the Nichia 219s a lot nicer than the XPGs that come stock on the 612.
Stars
Illumination supply didn’t get my message in time to add 16mm stars to my order. But that’s ok because I was able to reuse the original stars on the 612 with no problems at all. They were easy to remove from the pill.
Reflowing
I was a little lazy about moving all my stuff to the kitchen to try the stovetop reflow method. I ended up holding the star face-up in a vise and using my soldering iron to apply heat directly to the underside of the star. I used a screwdriver to apply light pressure to the side of the existing LED while heating up the star, and the LED just slid right off once the solder melted. Adding solder paste and positing the new Nichia LED before heating the star again with the soldering iron, I could clearly see the solder paste melt and knew when the remove the iron. Quite fun
Drivers
I tried powering the Nichia with the existing driver, and that worked fine. The stock modes on the stock driver are high>low>strobe. I don’t think I’ll need a strobe around the house, and I already had the Nanjg drivers, so swapped them out so I could have low>med>high instead. I took the springs off the old driver and solder them on to the new one. The new driver’s ground doesn’t make contact with the pill along the side when it sits inside the way the original driver does. I found it easier to solder the negative spring to the driver than to bridge the driver ground with the aluminum pill.
Thanks for the update. Man, you sound like a natural at this stuff. You’re officially a flashlight modder after doing all that. Congrats on the new lights.
