Mod: Small Sun ZY-T11 and ZY-T29 + overview and comparison


I have been thinking about making a thread about these little beauties for some time. I have used them for months, and lately started to mention them in some threads. A member wondered if I could do a thread about my lights. Why not? These are great lights. They are among my favorites, after they have been modded that is.

In comparison with other known lights:

Olight I6, OEM D4 (aka Convoy M1), ZY-T29, D4 (aka Xiaochi/Convoy S6), ZY-T11, Sipik SK 68, Ultrafire M5

I ordered them back in April 2013 (Some sale from a store named Meritline, I do not recommend them btw). One of the lights had a defect driver. There was no "off". Main problem with stock UI is that you have to cycle through all the modes in order to get to "off". Like the Supfire M6. I dont like that UI. Stock output on high was around 1,8-2,2A. I think the ZY-T11 was the one with slightly higher current.

No big deal as I considered them to be mod hosts, as basically all my lights. Due to the limited space, the light would require lots of mechanical work in the front in order to replace the switch with a mechanical one and fit a regular driver circuit.

The upgraded driver

Luckily, I did the smart and easy thing. I sent a PM to Drjones back then, 2 lumodrv was ordered. They work with electronic switches. I did not understand the UI that well based on the description. At that point I had never owned a driver with ramping before. But once you get the light in your hand, everything falls to place.

In short, its a 2 mode driver. But you can also start ramping from lowest output when the light is off. So in some way its kinda like a 3 mode. The modes can be programmed to the output you desire (its got 34 steps!) You can also easily adjust the 2 modes up and down too (ramping). If you turn the light off, it remembers the brightness/setting you used last. Its got built in battery monitor that can tell you the voltage of the battery. Its got hidden strobe, and beacon. There are also shortcuts to the various modes depending on how many quick taps you do. You can do momentary at the brightness level you want. Basically, you can turn it into a 1-mode that is great for signalling, of course, with the brightness you desire. :) Probably some minor things I have not said, but its a pretty sweet UI. The beauty of it its that its based on a nanjg 105C. That means the numbers of 7135 regulators can be changed for the current you want. I ordered mine with 8*350mA regulators. A total of 2,8A.

More information about DrJones drivers here and how they are wired inside the light (my mod thread on Fandyfire K2 with focus on these drivers). Picture of how its wired inside the ZY-T29 here.

Looking at the stock lights

Before I talk more about the modded lights. Lets look at the stock ones. What is the difference between ZY-T11 and ZY-T29. First off, Im not sure all of these are similar. My lights were not supposed to be branded Small Sun, but they were. Some sell them with Ultrafire logo, some with Aleto. sell them for about 10$ (Aleto). I believe Small Sun is the maker of these lights, but for all I know, the clones might be just as good.

Size of a compact EDC light.

Reflector width more like a P60.

Spill is wider than a P60, so its great for walking outdoors in the nature.

ZY-T11 pros

-Shorter than ZY-T29

-Stable tailstand (ZY-T29 is not that stable)

-Lanyard hole nicely placed on the tail (ZY-T29 have it on a weird place on the head)

-I like the clean look better

-Easier to soldier emitter wires sine the emitter does not sit that deep into the head (despite this, they have similar sized reflector)

ZY-T29 pros

-Came with aluminium reflector (My ZY-T11 came with a plastic reflector)

-No charge port opening

-Slightly thicker square threads on the tailcap (Still not "premium threads". Im perfectly happy with the threads on the ZY-T11 though. Threads are good enough on both lights)

To sum it up, I like the ZY-T11 better, but the ZY-T29 is technically better. :p

A few nice things. Head seems to be made out of one piece of aluminium. That means great heat transfer. Better than say, typical Convoy "S" or "M" series light that uses a screw in brass pill.

Reflector is fairly wide, but short. This gives great wide spill, but a bit of reach too (considering the size of the light). Dont get me wrong, its a mainly a close up light. With a de-domed XM-L you get both of throw and nice wide spill.

Lockout feature on tailcap (Warning, this makes you loose programming if you have done any. This driver is not like various other DrJones drivers that remembers the programming when you take out the battery). Edit: New drivers now remember programming when you take out the battery or "active" lockout (unscrew the tailcap a little).


Was decent. For a 10$ light I don't expect premium anodizing, and you dont get it either. But I was happy with the look. If you use these lights a lot, you will see some typical signs of wear and tear. I have a few minor marks on mine. But they have held up nicely.

I was so retarted that I took the switch out of one of my lights (when I considered mechanical swtich). Dont do that! I might be a PITA to get it properly back in place. I used a dremel to help me get the job done, and managed to scratch the head of my ZY-T29 in the process. Anodizing is not HAIII. :P


As mentioned, head design is deeper on the ZY-T29, which makes it harder to solder emitter wires compared to the ZY-T11. (reflector is basically similar size on both lights) Stock the MCPCB was 25mm wide I believe. I replaced it with copper MCPCB like I do on most lights. Since reflector on the ZY-T29 is made out of aluminium, its always nice to cover up the wires. In my case, I used kapton tape.There is also a white XM-L centering ring included.

The ZY-T11 (left) uses the Lumodrv as it came came shipped (mounted to the stripped down driver circuit that came with the light). Currently its even got stock wires from driver. These days I always replace the stock wires.

2,8A is a quite nice amount of current for these lights. On the ZY-T29 I just went crazy and added 3 extra 350mA regulators. Total output 3850mA. These regulators tend to overperform so I am actually measuring up towards 3,9 to the emitter. In order to get that current. Copper braided spring is required. The lights can use all type of 18650 batteries btw. A normal protected NCR18650B will only output a bit more than 3,5A when freshly charged. This is due to the Vf on the XM-L2. So Im normally using a protected 2900mAh Panasonic PD cell in order to get both output and runtime on top level. That battery have no issues giving me the full output. When battery (resting) voltage is down to 3,89V, im still seeing 3,4A to the emitter. When its down to 3,8V im getting 2,9A to the emitter.

I could always use unproteceded PD cells (which I sometimes use), or some low capacity cells that holds the current higher for a longer amount of time, but in all honesty. This is a small light, they are not really meant for extreme 3A+ current. But its fun, and when its so easy to adjust high up and down as you want, who cares if 100% output is stupid high. :)

You see that plastic ring around the spring (picture above) On the ZY-T29 I have flipped it and glued in in place. The only thing that avoids a short circuit is that plastic ring, and on my ZY-T29 it was dangerously close to not holding the battery away from touching the retaining ring at the spring at the same time. (ZY-T11 was better)

AR lens:

I have ordered from CNQ. Stock lens is about 1,6mm. AR lens is 2mm. I dont think that is an issue. And if I remember correctly, stock MCPCB is 2mm thick. Sinkpad/Noctigon is slightly thinner. I believe you end up with pretty much the same fitment as stock.

My (current) setup on these lights:

I dont remember all the combinations I have done with emitters in these lights. I change around alot on all of my lights. On the ZY-T29 I started out with stock. Then I used to have a de-domed 3C emitter in the ZY-T29 some time back (yes you read correctly de-domed 3C). Then an XM-L2, now another XM-L2. More specifically, XM-L2 T6 3A on copper. Ill use it as it is for a little time. Then i will de-dome it. Wires/springs have been upgraded. 3,85A to the emitter.

My ZY-T11 uses 100% stock lumodrv 2,8A. XM-L2 5B1 (80+ CRI) on copper. I might increase output to 3150mA, and do resistance mods, but its nice as it is.

These lights, and especially my ZY-T11 have been among my favorite lights since I got the DrJones Lumodrv in it and upgraded the emitters. And I have used them for months! :) Highly recommended mod lights!

Ill get back to beamshots in the future, probably some time after the ZY-T29 have gotten its emitter de-domed..

A few days ago I made a new version of lumodrv that allows to permanently store your changes :)

Edit: Answering the post below: Yes, all lumodrv drivers shipped from now on will have that.

Sweet, that is a feature I missed on the lumodrv. Is that standard on all the drivers that are shipped now?

thanks, I’ve been wanting to get some dr jones drivers (I really really want to get set up for uploading programs to the drivers) these two little guys look to be the size of my ideal holster edc and I love ramping drivers.

I’m going to put these down to order in a couple of months when I’ve cleared my mod bench.

Great write up, thanks for sharing.

The Ultrafire branded ZY-T11-clone I got from Banggood for $9.99 shipped (I ordered it as a ZY-T29 clone but received the other one funny enough) has an aluminium reflector, so that is nice.


Ok, thanks for the info. Edited OP a little.

Have you considered the following too?

-Low voltage cut-off. Say at 2,6V, its not like its much juice or light left in batteries then. I think its nice to have the protection. A true flashoholic always carries a spare keychain light anyway. Most have a cell phone too that can be used for emergency lighting.

-Low is nice and low, but is it possible to get it even lower?? :) (talking about the absolute lowest on ramping, not the default 1mode)

-PWM is nice and high, but is it possible to get it even higher? :)

Thanks for the feedback! Tell me how you like em if/when you get around to build them. :) They are fantastic lights with the lumodrv. :)

will do, I think I’ve got that ld35 sussed out too. I’ll report back tomorrow, it’s supposed to be constant current on all modes, we shall see….

Great write up RaceR86! I love the form factor of the T29 and T11 but my T29 is pretty anemic and I hate the UI. I tested mine tonight on an ET 18650 at 4.12V and it only pulled about 1.6A at the t/c and put out just shy of 400 OTF lumens after 30 seconds. Sounds like this Dr Jones driver is a great fix for both. I have zero modding skills but would be willing to try this. Thanks for the write up.

Thanks manxbuggy1!

I really like the form factor too! :)

Its not a difficult mod, but its not the first mod I would try to do either (for people who are new to electronics).

When that is said, my K2 mod thread goes fairly detailed through the process, hopefully in a fairly noob friendly way.

Just yesterday I was looking at ZY 29 reviews,Dr Jones’ Lumo and Mobydrvs and several of your threads and here it is now,all

together.I think I missed it by about 20 minutes!Ill definitely be getting in contact with the good Dr shortly.

You say the zy 29 has square tailcap threads,have any of the others in the comparison lights got square threads,

Olight probably,D4/Convoy S6?I won’t ask about a Roche F12 cos that would be off topic :wink:

Anyway,great thread and loads of ideas,thanks RaceR86.

Im not a threads snob.. :p (if there is such a thing)

Olight I6 have fairly thick nice square threads combined with O-ring that gives it a quite perfect feel. I think the Convoy have square threads, but they are just fairly small? Not sure..On further inspection it looks like my ZY-T11 also have square threads, but they are much thinner than on the ZY-T29. (ZY-T11 on the right side). Or maybe that does not count as square threads?

(Sorry about the grey silicone grease)

Here is the other end of the tube.

They can not be compared with the top notch square stuff in any way, and they might require some grease in order to feel smoother and avoid squeel. Threads are no more than average. They get the job done though. :)

Glad you found the thread useful! :beer:

Thanks for the info,there is another reason I’m collecting a data base of square threaded potential hosts.

I’ve been playing with QTC’s and made a pill that doesn’t twist the QTC.I put one in a tiny ultrafire 16340

twisty and it worked fine.One day,it didn’t work,check battery voltage,2.not much volts.I beleive it’s called

hysterisis - the silicone rubber QTC takes it’s own sweet time to return to original shape and in the process

,remake the contact.

I decided to try clickies so, first off,a Cree 10B 16340 with a Q5 (xpe,xre I don’t know).

Anyway,it was a revelation , much more controlable and sensitive.Why? - because there’s a pair of threads at

the tailcap,and another pair at the head/body so I could adjust both individually for brightness.

If I’m using tailcap and head threads as the infinitely variable brightness control,thread performance(never

imagined I’d see myself write that expression :bigsmile: )becomes an issue (obsession).Hence”are the threads

square on ……”

Damn, I’m gonna have to start my own thread on this stuff now! :stuck_out_tongue:

Thank you for doing this mod thread and the K2 mod thread. I already got a second K2 to mod, and ordered one of these to mod as well. Now I need to order a drjones driver. I can't wait.

Billy X, if you are a "thread snob" these lights are nothing special. The lights might also be like various other Chinese lights. Limited consistency in how they are made.

These are 10$ lights, I have no complaints considering the price for the "host". Grease, oil normally makes threads feel better anyway.

As long as they don't break or squeal , feel fairly smooth, and are easy to screw on, then Im happy. :)

Leftye. :beer:

I ordered (/killed) a 2nd K2 aswell.. 0:)

(I blame WB)

That's how I got my second one. It's already been delivered. It's a great deal.

Well, I did have that idea, but the number of features I can press into that small memory is limited, and I found other features more interesting.

Well, yes, maybe, depends... The lowest mode is at the edge of PWM resolution and on the edge of AMC7135 activation time. The MCU provides power to them, they take a while (~2µs) to actually awake, and at that time the MCU drops power again already.

The problems with QLITE arise from that (flickering in the lowest mode, or lowest mode not even lights up the LED).

That's why I use a slightly higher, but safer minimum value.


-PWM is nice and high, but is it possible to get it even higher? :)


Yes, can go to ~35 kHz, and even higher at the expense of PWM resolution - but why?

It also increases problems with the lower levels.

I was just curious why the lumodrv have 8kHz PWM, when several of your other drivers have 19. Higher seem to generally decrease the chance of audible and visible PWM.

Thanks for the answer DrJones! :)

Moving my comments to this dedicated Small Sun ZY-T11 thread.

The DX US$15.20 Small Sun ZY-T11 has a couple of issues:

- it has a plastic reflector even though they advertise it with an aluminium one.

- it comes with no clip which they advertise

  • it has a lens defect on the glass as shown in image below.

Good news is there are clones the do not have the lens defect, have an aluminium reflector and are cheaper. Aluminium reflector confirmed on Aleto version by ebayer Aletocn , Ultrafire version also has an aluminium reflector as confirmed by BLF user djozz .

Small Sun ZY-T11 clones - aluminium reflector

Ultrafire version

US$9.52 flashlight - banggood
US$11.09 flashlight + wall charger - banggood
US$17.59 flashlight + wall charger + 1xunprotected 3400maH Panasonic 18650 battery - banggood

Aleto version

US$9.99 flashlight - banggood
US$10-$14 flashlight + car&wall charger - ebayer Aletocn
US$10-$14 flashlight + car&wall charger - ebayer aletotop2012

Small Sun ZY-T11 - plastic reflector unless noted, slighty whiter cool white emitter

US$10.99 flashlight with plastic reflector - banggood
US$11.11 flashlight with aluminium reflector - banggood
US$12.20 flashlight - fastcardtech
US$12.48 flashlight + wall charger - banggood
US$15.20 flashlight - DX

Chargers and batteries

The Small Sun ZY-T11 charges protected 18650 fine from an old old 3.5mm ended Nokia charger (5.3V). My Aleto came with a 4.2V+–0.5V @500mA Chinese charger.

Best to avoid any Ultrafire/Trustfire or other Chinese 18650 and grab Japanese Sanyo/Panasonic or Korea Samsung protected cells. They cost a few $$ more but have shown to have far longer runtimes. Not worth getting an inferior product for the critical engine that runs the flashlight. Eg:

US$9.53 Authentic Samsung ICR18650-26F 18650 2600mAh@3.7V Protected Rechargeable Lithium Batteries

US$11.03 Sanyo UR18650F 18650 2600mAh@3.7V Protected Rechargeable Lithium Batteries (2-pack)

US$13.70 Panasonic Protected NCR18650A Rechargeable 3100mAh@3.7V 18650 Lithium Batteries

US$16.73 Panasonic NCR18650B Protected Rechargeable 3400mAh@3.7V 18650 Lithium Batteries

Tests of individual (different brand & capacity) 18650s: 18650 tests

Above: DX US$15.20 Small Sun ZY-T11 lens defect