D.I.Y. Illuminated tailcap

I am going to grab some of those as well, can’t really argue with the price.

Also grabbed some pots from this seller: http://www.ebay.com/itm/400925630541?var=670469147267

Lots of other interesting stuff in his store if you need anything oddball and he appears to give shipping discounts as well.

So, what’s the best way to approaching this for the first timer? I wish there was a video of someone putting one together for a light as common as the S2/S2+. I understand that the need for a bleeder resistor on the driver and the resistor values for the SMD LEDs will vary depending on what you’ve got, but a simple “here’s how I do it” would be really valuable in saving some of the headache for the less experienced.

I’m going to be attempting one for my S2+ (rubber switch boot) regardless of any video. It’s a triple Nichia with a MTN17DD FET+1 running A6 firmware.

If I understand it right, I need to decide if I’m going to use a nylon spacer or a TOP board for the switch. I’ll likely choose the top board. I already have LEDs coming, and resistors are soon to follow (getting the variety pack from FT). Depending on the board design I choose, I need to either stick with trying various resistors or using pots. This is where my knowledge tapers off… :slight_smile:

I’ll reread some of the info in this thread to see if there’s more that I might have missed. Maybe I’ll try the search function again with some other terms…

Please keep us posted. I too am about to embark on my first journey. I have most of the stuff and waiting on OSHPARK. …but as you said it sure does help all the little pointers for first timers. I’m the guy who didn’t even like lighted tailcaps. So much for that! LOL

I wished for the same thing. I’m waiting for my boards to show up from Oshpark. I doubt I’ll do a video, but I’ll take a lot of pictures and notes from putting them in my S2, S2+ (metal tailcap), and S6. Maybe C8, too. We’ll see how adventurous I get. I’ll share as soon as those are done.

Super!

Step1: Choose what version you want (and ask questions to help decide).

Step2: Solder all components to bottom of switch pcb (spring, bypass wire, pot/mini switch).

Step3: Solder all components to top of switch pcb (omten switch, pot/jumper pins).

Step4: Solder all components to bottom of Ring pcb (Pots/resistors).

Step5: Solder LEDs to top of ring.

Step6: Assemble/mock-up to test (preferably with actual driver being used in the light).

Step7: If it works, great! Finalize your assembly and pat yourself on the back. If your driver is acting funny, move to step8.

Step8: Read OP about bleeder resister. Add bleeder resistor to driver. If it works, great! if not, move to step9.

Step9: Tell us why steps 1-8 didn’t work for you.

Appreciate the cheat sheets.

Honestly - that’s very helpful. I appreciate you “dumbing it down” for us ambitious folks lacking the practical knowledge. So, what I’m trying to say is, THANKS!

I finally got around to actually putting one of these together today, well 2 actually. Overall it went together easy enough, I like the header pin setup.

The pot is hard to dial in, maybe it is just the ones I ordered. I tried both 50k and 100k but I find that the LED’s won’t light up with anything over ~5k at the most. Why such high pot values?

Besides that the tailcap works great.

The driver on the other hand seems to loose reverse modes with the tailcap installed. I guess because power is flowing through it at all times?

I am using a TA driver with a 560ohm bleeder but also tried it with a another light that didn’t have a bleeder and while the tailcap lit up it lost all modes.

So is this a sign of a larger bleeder resistor needed?

How bright have you set you LEDs? If You can’t see them at all in a bright room, I’d make sure you don’t have any trickle shorts anywhere. It’s odd that you have to set your pots so low, I have to totally max out a 50k to get anything usable.

If you find out where all the extra power is going, that should resolve your driver issue. But otherwise, yes you’re describing symptoms of not enough bleed.

They are about as bright as a stock astrolux S2 tailcap I would say, maybe a bit less.

I built 2 of them, I have not tried the second in a light yet but it needed about the same pot settings. It uses different LED’s and it is significantly brighter though. Both of them have a very narrow window where they will light up at all, be it in the flashlight or on the power supply.

I could not detect any shorts with the multimeter besides the pot bleed.

I guess I will swap to the 2nd cap and see if it does the same thing.

If they draw more power than the banggood tailcaps, you will need more bleed. Banggood had to use a 420ohm on their drivers.

Most of us like them much dimmer though, which pulls less power and you can get away with less bleed/less vampire draw. I use a 1kohm resistor these days.

The S2 tailcap looks to draw about .5ma and one of these pulls 1ma and the other 5ma (the 5ma is dimmer though but I think that may be due to the LED’s, when tested before installing them they were much dimmer as well).

I basically can’t adjust the brightness as minute changes to the pot will cause them to not light up at all, I just feel happy when I get them to light up, there is maybe 1/10 or less of a turn for the entire “adjustment range” if you can call it that. The worst part is that the “working range” of the pot seems to move around the pot so it is nearly impossible to find it again.

What pots are you using? The ones in the OP? I might need to order some and see if that is the issue.

As it is I would just find the correct resistance and use resistors, it is easier then this.

I just ordered the cheapest 50k and 100k pots I could find on ebay. I get adjustment through most of the range, although the change isn’t dramatic, and there is a small section where the pot is essentially ‘off’, no throughput.

5ma is utterly ridiculous, I wouldn’t put that in a light at all. Most of mine draw 0.1ma-0.2ma, or 0.5ma if I want it really bright. You might just have some really inefficient LEDs or something?

The 5ma one sucks anyways, the green is “80’s power LED green” and dim. I have several others to pick from, might try some of those I just got in from ebay and see if it makes a difference.

The 1ma is brighter then the S2 now that I compare them so it seems to be working ok. These are both 0603 LED’s though but that should not make a difference.

I haven't look at how these boards are wiring the Pots. I think Pots are typically wired with a leg to ground and used as an adjustable voltage divider. So the more resistance you assign to the load, the less resistance is assigned for the excess voltage/current to flow to ground. So I would think low resistance pots would let more current flow through them, especially if you have the LED's dim.

We never connect the other leg of the pot, so there should’t be any extra drain there

Ok, I just built another one, these are all using the 5.3 bottom and top boards with a jumper on the top resistor pad and 3 LED’s installed.

This one was in purple (which looks real good BTW) and after playing with the pot for awhile I finally got it to light the LED’s with around .4ma.

Tested on the flashlight and it worked, both forward and reverse modes. Once again the final resistance was under 10K (didn’t measure it after putting it in the tailcap). The pot has virtually no adjustment window to work with and it is a real 50k pot when tested.

No idea why it takes so much less resistance.

The glow is VERY dim like this as well, only if you look would you notice it in a lit room. It acts the same weather installed in a light or run off the bench power supply. I can detect no shorts with the multimeter.

Quite strange.

I think you’re just setting them brighter than I do, and that’s causing extra draw and less resistance being needed. No idea why your pots seem finicky.

In most of mine you cannot see the glow at all with direct overhead light. Otherwise they are too bright with dark-adjusted eyes.

Your 560ohm bleeders should be fine with anything under 0.5ma draw. Nothing scientific about that (that I know of), just from experience.

To be honest I haven’t even tried to figure out how bright I want them, I just am glad when I can get them to actually come on, it is a matter of breathing on the pot and hoping it was enough to make it come on without over shooting and having to start over lol.

I will see how these look tonight and that will give me a better idea of how bright I want them.

The biggest issue I want to figure out is why it is taking so much less resistance in mine? What color LED’s are you using? So far I have used green and purple, they all have had a VF of ~2.3-2.5v, so pretty high and I am guessing why they need so little resistance.

I might do a red one next which should have a lower VF to see what it does.

Overall they look great, just the details I am trying to sort out.