Lumzoo GH10 Review & Modding/Fixing

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will34
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Lumzoo GH10 Review & Modding/Fixing

This is a short review for the Lumzoo GH10 angle light, which I purchased from BG the same day it was released and had an introductory price of $30. I’m a big fan of headlamps and when I saw this strangely shaped square head angle light being called the world’s shortest 18650 flashlight I didn’t hesitate to order. It also had very positive reviews on the Russian and Chinese forums, and I could confirm this the very first second I had in in my hands.

Packaging & contents:
No packaging at all, just a transparent ziploc bag with the light, a generic low quality headband and a spare o-ring, not even worth taking a picture, you can imagine it. For me it was fine because I hate fancy boxes, I like paying for the quality of the product not the packaging.

Build quality, size & ergonomics:
Let me start with the first interaction I had with it: it has been a couple years since the last time I experienced a tailcap screw this smoothly and that was on a zebralight H600. The threads on this lumzoo are perfectly machined and the oring has optimal pressure, making the twisting action very precise, smooth and with zero play. It is constructed from a single piece of aluminium and although looking square there isn’t any sharp corners or angles, I would say the machining is top notch and on pair with zebralights. Anodizing is well done and seems durable, it is less matte than armytek finish but not as shiny as skillhunt.

The size of this thing is simply mind blowing, barely longer than the 18650 it uses. It has excellent ergonomics and can be perfectly one hand operated in both handheld or headlamp form. When I first had it in my hands I could not believe this was a 18650 light, there are 16340 lights that that bigger and heavier than this. However for a light this compact there must be sacrifices, as it ONLY accepts single wrapped unprotected cells.

Look at how tiny it is compared to an unprotected 18650, a stripped down ZL H600, Skillhunt H02R, Armytek Wizard V3 and a Convoy S2+.

The battery compartment is so tight it barely accommodates a single wrapped cell.

It comes with a very sturdy deep pocket clip which allows it to sit fully inside your pocket. Due to the flat sides of the head the clip doesn’t spin but can be moved either side. This is one of the best clips I have tried.

Operation, UI & performance
The GH10 is operated via a single electronic switch on top and it is pretty amazing: unlike any other e-switch light I have, this switch is completely silent and requires minimal effort to operate, while still providing good feedback. Imagine the home button of a modern smartphone, but even softer and quieter. There is also a small red LED on the switch pcb to indicate when battery level is low by flashing when OFF. UI is as simple as it gets with 5 modes, click once to power ON/OFF and hold for modes. There is no strobe or aux modes of any kind.

Spec says 1,200 lumens on turbo but of course this is not true since it only draws 2.83A from a freshly charged cell. The driver is 7135 based with 8 chips and controlled by what appears to be an Attiny85. One amazing feature (or lack of) is that there is no step down, however this might be a con for some users. Because of the unibody construction the heat spreads evenly and I could still hold it comfortably after 3 minutes in turbo.

The performance of the GH10 perfectly matches the skillhunt H02R with only 3% variation in current draw and output measured via ceiling bounce. The Lumzoo however felt sightly brighter because of a more intense beam produced by the larger and deeper reflector. It performs excellently as far as stock lights goes.

The review would have ended here and I would have rated this light as excellent with 4.5 stars if everything continued to work fine…

.
.
.

However…
My happiness did not last long because just after a few days of moderate use, one night it suddenly started flickering like crazy while being OFF. It wasn’t the battery or bad contact, the driver just stopped working like it should. The 3 lower modes would flash in the same intensity no matter if on or off and the two higher modes would still work. See the video here: https://www.youtube.com/watch?v=7VWFqWiya5Q

After several emails with banggood, 2 videos and a bunch of pictures, their “professional guy” named Zoe was still asking if I used 2xCR123s or only 18650s, and if I have tried with a fully charged cell… I was patient enough to answer all of her questions and they finally agreed to sent me a new one free of charge. I said no need and opted for bangood credit to make things easier for them and also because I didn’t wanted 2 lumzoo GH10’s. Let’s see if they agree.

Fixing/Modding
Now that I don’t have to send this unit back to China I can proceed to fix and mod it:

By removing the 4x T5 screw on top the switch boot retaining plate goes off and the switch pcb is revealed, however not much to do here, the driver is glued and pressed from the other end.

Driver is out, 17mm, 4×7135 on each side, with 5 teflon wires out of it: ground, LED+, LED-, switch, red LED+. The ground contact is obtained by the back of the switch PCB which touches a ring of unanodized aluminum.

The front SS ring can be unscrewed by pressing it against a grippy surface like the back of the mouse pad. Once it is removed you can see the thin MCPCB secured by two screws with some low density thermal paste in between. The emitter shelf is about 2mm thick.

The stock MCPCB is copper and DTP. I decided to not replace it with a noctigon due to the thickness, instead I reflowed a XP-L HI V2 1A on it.

I have been keeping a very special driver for years waiting for the worthy host to use it on. This is with no doubt the perfect opportunity. Can you guess what driver is it? It’s quite obvious… Smile Here I’m testing the driver and everything works fine, except the red warning LED of course. I always use a discharged cheap cell to bench test, less likely to burn anything in case of a short.

This driver is almost the same thickness of the stock one and the fitment was spot on. I potted the top side with some arctic epoxy. Because of the added front spring there is now ~1mm additional battery room, but still only accepting unprotected flat tops.

The HI emitter and this semi OP reflector is a perfect match, producing a very smooth beam with zero artifacts. The beamshot above is after the mod.

Modding difficulty: Medium
The hardest part was to fit all the wires in that tight space, I had to savage the 24AWG teflon wire from the old driver because 22awg silicone ones were too thick. If you only want a LED swap that’s an easy task. After the mod current draw dropped a little bit to 2.72A (the standard from the new driver), but now it has a much UI, better throw and a pure CW tint thanks to the XP-L HI V2 1A, The stock V6 1A was a bit too blue for my taste. I must say I’m very happy with the new internals, this will be my new EDC when I need to carry something compact.

Hope you enjoyed the read Smile

Edited by: will34 on 08/20/2016 - 05:03
quetzalcoatl
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Thanks will 34! After a flood of Orcas and Olights torches, finally a review I was waiting for.

MRsDNF
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Nice recovery with the mod. I have no idea what your driver is.

 

djozz quotes, "it came with chinese lettering that is chinese to me".

                      "My man mousehole needs one too"

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

mattlward
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That is a very unique light, kinda like the look of it… Is there a magnet in the tail cap? That driver is very interesting… to bad it crapped out. Would love to find an e-switch driver like that, would not cannibalize a Zebra. Zebra’s are not budget lights! I have been trying to find a deal on a NW AA Zebra and have had no luck, do not even mind used and abused. This light is a little pricey as well considering it died early.

Matt

EDC rotation:
FW1A, LH351D 4000k (second favorite)
FW3A, LH351D 3500k
FW3A, SST20 FD2 4000k
FW3A, Nichia 4000k sw40 r9080 (favorite light!)
FW3A, Cree XP-L Hi 5A3
Emisar D4V2, SST20 4000k
S2+, XM-L2 T6 4C

MG
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That’s quite nice little hunk of aluminum. Tempted, if it weren’t for the malfunction. Nice review/mod!

JohnnyMac
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Great looking light! I was really tempted to pull the trigger before getting to the bad news of your review. I don’t think I will now that yours died so easily and quickly. Damned shame. Almost sounded like the perfect headlamp in that format. Sad

will34
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Banggood promptly solved my case with a full refund via paypal, I was surprised they didn’t even mention partial refund or having me to send it back. I hope that would help you guys pull the trigger, it is an truly excellent light even in stock form, this kind of build quality I have never seen in a budget light. The snap-on clip is one of the best yet, many times more solid than the convoy one.

Do keep in mind that it only takes unprotected flat tops, which is acceptable BUT the cell can’t have double wrapping because it will get stuck and a PITA to get it out. Since I like to clear wrap my bare cells for extra protection I had to remove the wrap from a pair to use them only on this light. It is also not very convenient to use this as a headlamp because the square back corners bumps against the headband rubber piece and won’t allow it to smoothly adjust up and down.

The reason I took the ZL driver out was because it got salt water ingression and they were asking $25 for repairing the reflector and e-swtch PCB, adding shipping to China was $50, not worth the hassle for something that costs $80 new.

Nicolicous
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This light reminds me of a hammer from Thor movie Silly

Nico -.-

Bruno28
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With the change in driver and led, do you think it now produces 1200lm?

What driver did you use?

will34
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Bruno28 wrote:
With the change in driver and led, do you think it now produces 1200lm?

What driver did you use?

With the new XP-L HI it now has increased intensity but reduced lumens, I would it it is close to 1,000 led lumens but OTF is about 850 at best. The replacement driver was taken out of a Zebralight H600 1st gen and draws 2.72A, 100mA less than the stock driver.

1,200 lumens as claimed by the manufacturer is not possible to achieve with just 2.83A draw at the tail, but I would say it is very close to that, in LED lumens of course.

In terms of output the GH10 can easily stand against a flashlight rated ANSI ~1,000lm.

Bruno28
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what if i put a A17DD-L FET+1 Driver in there?
http://www.banggood.com/Astrolux-S1-BLF-A6-A17DD-L-FET-1-2_8-4_35v-7-4-Modes-Flashlight-Driver-p-1009980.html

would it get me more modes and higher output?

will34
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You could use a FET driver but that one is for tail clicky switch only, for this GH10 you would need a FW designed for electronic switch.

With the stock emitter you could expect about 1,600lm on the highest mode, and this light certainly has the mass and the DTP board to handle that power.

Bruno28
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will34 wrote:
You could use a FET driver but that one is for tail clicky switch only, for this GH10 you would need a FW designed for electronic switch.

With the stock emitter you could expect about 1,600lm on the highest mode, and this light certainly has the mass and the DTP board to handle that power.

could you please recommend me a FET driver that could work with this?

bikenber73
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I went ahead and decided to give one a try.

We will see it yours was isolated incident or not.