Rustu XL-03 mini zoom Sipik 68 replacement - review and mod

I just received a Rustu XL-03 from Dealextreme

Rustu XL-03

My initial impression was good. This thing is tiny. It’s slightly shorter (comparing both lights with bezels retracted) and MUCH thinner and lighter than an SK68. It’s even thinner and lighter than an SK58. The beam profile is also very similar to an SK68, with about the same width in flood mode and the same spot in spot mode. Opening it up I found the following:

Lens diameter: 15-16mm from the front. The lens is smaller than that on an SK68, so I’d expect spot mode to be slightly dimmer if the emitter and driver were the same.
Emitter: Cool white Cree XPE
Star: 14mm very thin aluminum. Zero thermal grease under the star.
Driver diameter: around 14-15 mm (same as a Sipik 68), but the body tube around the pill is narrower than the Sipik.
Pill type: Aluminum, with a solid platform under the LED. There are 2 holes in the edges of the pill for snap ring pliers (or a large paperclip)
Tailcap: standard cheapie switch held in place with press-fit plastic retaining ring.
Clip: removable. Held on with a ring around the tailcap behind the o-ring. Unlike most clips, this one cannot slip off as it goes all the way around the tailcap.
Switchboot: 12mm orange color
Tailstands: yes

Not bad for a small zoomie … similar performance to a Sipik 68 in a much more pocketable size. It feels like it’s half the size of the Sipik!

Modding potential:
Of course, I’d never stop with an unmodded cheapie zoomie… so I spent some time last night doing a quick mod to it. I performed the following mods:

1. removed the driver and replaced with a 2.8 amp 3-mode Nanjg 105c I had laying around. When I mod Sipik 58s and 68s, I’ll file down the edges of the driver and then glue it to the bottom of the pill with arctic alumina. I attach a bit of solder braid to the ground ring and drape it alongside the driver so it hits the threads.
2. Since the body tube on the Rustu is narrower, more filing was needed. I almost completely filed off the ground ring around the edges of the driver, and then filed the corners of the 7135s near the edges of the driver. I did this until it would slide cleanly into the body and fit at the end of the pill just outside the original driver socket.
3. For negative connection I soldered small pieces of solder braid to the ground tabs of 3 of the 7135s near the edge of the board. When the board is pressed into pill, the edges of these braid pieces hit the inside of the pill making ground connection. I then glued it to the bottom of the pill with arctic alumina. After repeated assembly and disassembly the arctic alumina didn’t hold, but turned out not to be necessary since the pressure from the battery acts to press the driver into the pill and gives a good connection.
4. I replaced the cool white XPE with a 5000k neutral white XPG2. I used the stock aluminum star, but added AS5 thermal grease underneath. Some time when I have more time, I may try filing or sawing down a 16mm Noctigon or Sinkpad to fit, but I figure that will take awhile.
5. I bent a small strip of aluminum into a “C-ring” and fit it around the top of the pill threads. This ring keeps the pill from socketing fully into the body. It’s purpose is to increase the travel of the bezel and allow the emitter to sit closer to the lens in flood mode for a wider beam while not affecting spot mode.
6. I replaced the driver spring with 2 small copper disks.

Result: It’s now a 3-mode XPG2 light. Much brighter than stock, with similar throw and a wider hotspot. I’m running it on Kinoko IMR 14500s from Illumination Supply.

Additional mods I might make to this light:

  1. Cut down a small reflector from an old UKE lamp module. I’ve done this in the past with zoomies. It adds a large hotspot to the flood beam, making for a much more useful flood. It also adds an ugly donut around the spot in spot mode, but the donut is dim enough it’s really only a factor in white wall hunting and doesn’t affect real-world distance viewing.
  2. Disassemble the tailcap and solder-braid the spring. Also change the orange switchboot for a black one.
  3. Replace the 3-mode driver with a 4-mode one that has moonlight.
  4. Replace the stock star with a direct copper star that has been filed or cut to 14mm. This may also make it necessary to readjust the focus on the lens as it would be much thicker than stock.

I also received a second light from DX that looks very similar to the Rustu:
Another 14500 zoomie

This one is the same size with the same basic dimensions. The parts are interchangeable. However this one has the following differences:
Driver: 3-mode (100–50-strobe)
Emitter: Cree XPE, slightly more neutralish tint than the Rustu
Pill: seats a 16mm star, but it’s hollow. Also this pill has an oddity: look in the top of the light and there are no holes for snap ring pliers to unscrew the pill. I ended up drilling holes in the plastic disk and using those to unscrew the pill.
Bezel: same shape, but external styling is slightly different.
Body and clip: body is same shape, but clip slips into a slot in the side of the body rather than being a ring around the tailcap.
Tailstands: No

I concluded the Rustu is better due to its tailstanding and solid pill.

Thanks for showing us your mod and thoughts on the two lights.

Took apart the switch today.

There are only 2 pieces inside the tailcap:
(a) a single module containing the switch, contacts and spring, and
(b) the 12mm switchboot.

Because the switch mechanism is a single sealed module, braiding the tailcap might be either extremely hard or impossible.

However, the inside of the tailcap has about the same dimensions as an SK68. I swapped in the switch guts from an SK68 and it fit fine. It was slightly loose, but a little gaffers tape around the retaining ring fixed that.

Removing the switch on the Rustu was easy: just press really hard on the switchboot and push the mechanism out.

The one with the longitudinally fluted head appears to be the same as and other places. I suspect that, regardless of brand, all the similar lights with this scolloped fluting come off the same fast production line. Perhaps the fluting is extruded.
I have one on order like the other one with the transverse grooves on the head.
I am expecting these and similar to become very common and even cheaper, perhaps replacing all those very cheap multi- 5mm, 3 x AAA lights.

You’re probably right.

The 2 different lights I purchased weren’t manufactured together though. There are too many internal differences. I noticed today that the pitch on the pill and tailcap threads is different from eachother … the parts aren’t interchangeable.

I got my 3 mode with the light, nearly circumferential cross markings. I ordered it from the same Dx listing as above. It is clearly an architectural copy of the fluted type. My example is brighter, both on Ni metal hydride and on Li ion cells and is warmer toned. I don’t feel that it is really worth US$ 5.83, except maybe as history. I think the $2 that I paid for the first fluted one is more like what the price will be when production and distribution get rolling.
Reading # 5 mod.:
What I did was to file off the smooth back part of the sliding head where it butts against the body. That increases the flood and therefore the maximum total light output. It also lets more light out with the lens and bezel removed but the sliding head still in place, in candle mode.
Your moving the pill forward has a similar effect on flood, without effecting throw, but it ends up slightly longer than mine, with the same function. Maybe that makes better space for protected cells?

Good idea filing the bottom of the bezel off.

My method leaves a bit more room in the tube and doesn’t damage the external anodizing. Helpful since the Kinoko cells I’m using are just a bit too long without this. Your method results in a smaller light…. and since this light is all about small size, anything that makes it even smaller is a plus.

Tonight I reflowed the LED from the stock star onto a filed down Noctigon. Unfortunately, the downside is that the light no longer quite focuses in spot mode since the Noctigon is much thicker than the paper thin stock star. There are 2 ways to solve this:
(1) file down the bottom of the pill’s “lip” (the part with the o-ring), to allow the bezel to retract further. Doing this with as handfile without accidentally sawing through the incredibly thin side of the pill could be difficult; or
(2) add a spacer to make the lens sit slightly further out than stock. Something to prevent the lens from screwing down all the way. Perhaps another o-ring. I only need about 1 mm.

I added an o-ring between the bezel and the moving head to the SK68 I put a thick copper star on. It feels solid and works fine.

I wondering the space between the driver and the ring where the base sits, if it would be epoxy/RVT a copper plate on the back side of the shelf, leaving a “pit” in the hollow emitter tray, then epoxy/RTV (even solder) a smaller copper 10mm Noctigon or sink pad, allowing to countersink the emitter but still retain the ability to pull the heat away from the emitter, and not throw off the focal length of the aspheric lens…hmmm

I filed down the Noctigon back-side to get it sitting lower. I've built these with both an XM-L2 and XP-G2, sanded the bezel down to widen flood mode - how Fritz posted and that worked great. 2.8A though has to be insane heat in this light.

In stock form, I've found them quite lower output than an SK68 on similar Lion cells.

Great thread.
And great mod
This is a good light stock.
I have several of each kind.
Some from bang good. Some from eBay
Another difference is that
the lens goes in through the front of the bezel on one.
and through the back of the bezel on the other.
I recommend this light, even though the switches are weak.
The 20mm diffuser from FASTTECH fits it to make a great
Candle with 1.2V
If I did not have a $50 edc, I would carry this.
The sk-68 is fat and obsolete, now.

Edit: I find it odd that these lights are made by two different factories,
Yet look identical . How does this happen ?

I tried to solder braid the tailcap switch on my XL-03 last night … and failed miserably.

The switch module is a sealed unit, with the end of the spring sticking out. The portion inside the switch mechanism is shaped sort of like a Christmas tree… tapering to a point at the button, then widening, near the base of the switch housing, then narrowing to a narrow spring that projects though a hole and touches the battery.

I was able to get it in and out by unscrewing it, but my attempts to solder braid the tiny spring failed and I ended up destroying the spring trying to remove it. I then replaced the switch guts with the switch and spring from a Sipik 68. The Sipik 68’s much bigger spring was much easier to solder braid.

TIP: one problem I’ve had with Sipik 68 and 58s is after the plastic retaining ring is removed, and then replaced it often starts to slip out on its own with repeated usage. This is because I have to damage the plastic retaining ring in order to remove it. To stop the slippage, I took a tungsten tip etching pen and carved horizontal lines on the inside of the metal tailcap. These lines act like knurling and stop the plastic retaining ring from slipping out on its own.

Is the diffuser this one This is 20-24mm rated.

I took out the tailcap assembly too and saw the spring/switch one piece issue and backed off trying to copper braid, but mine are running at 1.2A so not really needed.

Lol. That would make a C8 useful only as an anchor, as it is much bigger than an SK98 which is just a scaled up 68. The 68 and 58 have larger lenses, which gets more of the light out the front, and the SK68 needs its size and fins for cooling when it runs a long time in high mode, especially in modified form.

Do you sell any lights that you mod.
I would buy this just to see what you did.

Sorry, I don’t sell my lights. But I might get around to posting pictures detailing what I did.

i have been buying the 20-25mm diffuser.
it works great on this light.
i think the 20-24mm is new.
i never noticed it before.
i have to get some because i have a huge diffuser addiction.
i have every kind that i can find.
i have a white one for my i3s that gitd green
when you take it off.
i have white red and green flat-tops for my d25a
syringe covers make good diffusers.
i have to use semi-clear plastic cups
for my SRKs and M6s
and i need them and use them all at the same time
to light up a big dark space with a high ceiling
for about 3 hours at a time.
i lay them on a shelf
and use the clip on this little neo-68
to clip 6 of them on an otherwise useless lampshade

yes only as an anchor. because the C-8 is hideous
i consider the 68 an “inbetween” light
because there are many better lights that are
smaller and brighter for front pocket edc.
and many lights that are much brighter
but only a little bit bigger for back pocket carry.
such as the 98 or any other 18650 light
with 24mm reflector.
i only use the 68 as a candle in case of power outs…
i have them scattered around the house.
they have many other uses and are one of
the best deals ever found.
but obsolete for edc carry unless you can afford
only $4 for a light. and again, only obsolete
because there are better lights for
almost every application, and now because of this
new neo-68 which is suitable for front pocket carry.

and the C-8 is so ugly i can barely look at them anymore
after trading for my Keygos KE-5 which is the prettiest
light of that type. you have to see it in person.
and with direct drive, you know big fun is on the way.

The Sipik 68 switch works very well in this light, but I find the loud click irritating.

A few years ago I purchased 3 electronic tailcap switch mechanisms from Steve Ku at Veleno Designs. These were originally intended to be sold with his limited edition titanium tailcap switch for the V10R. Back when they became available, I thought they might make a good switch for my modded Sipik 58, so bought a few of the electronics. These are pretty nice tailcap switches, consisting of a tiny circuit board with contact and tailcap spring, a microswitch on the top, and even a miniscule battery to power it.

In my Sipik 58 I ended up going a different route, by making my own electronic switch mechanism with wiring to the driver so it would be compatible with DrJones Lumodrv. As a result, I ended up not using these Steve Ku electronic switches.

I stuck some solder braid onto the negative contact of one of these leftover switch mechanisms and stuck it in my Rustu XL-03. I used a bit of spring steel wound up inside the plastic retaining ring to insure it would tightly grip the tailcap and not pop out. I also solder braided the spring.

Works out pretty well. Took a bit of trial and error in filling the switch boot to get the pressure needed to cycle the switch just right. Now the switch is much quieter, however the button must be depressed twice rapidly to switch modes as there’s no more half-press.