[sold out] SKY RAY 6 x Cree XM-L2 T6 3-Mode Cool White Light Flashlight - Black (4 x 18650) US$ 25,76 free shipping @ DX

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ImA4Wheelr
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Nice test dchomak.  I'm sure you addressed this and I just missed it.  Isn't the limit on that HF DMM 10A?

RMM
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ImA4Wheelr wrote:
  Isn't the limit on that HF DMM 10A?

Yes, but it will do more than that for short periods of time, I've done 13-14A with it.  My first one didn't handle ~20A very well though.

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dchomak
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ImA4Wheelr wrote:

Nice test dchomak.  I’m sure you addressed this and I just missed it.  Isn’t the limit on that HF DMM 10A?

RMM is right, little known fact, it will measure up to 20A but the hardware can’t take the current.

RMM, preliminary results look like you are right about my connections. I am in the process of charging that pack up right now. I will update shortly

dchomak
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Back to the HF meter measuring up to 20A.

Notice all the other scales on the meter start with the number 2. There is a reason for that.
When this meter measures 10A, what it is really measuring is the voltage drop across the 0.01 ohm shunt resistor. Using Ohms law that would be 0.1V. To measure 20A it would be measuring 0.2V, and we know the meter can measure THAT.
It’s using that scale when in 10Amp mode.
Now the reason for all the scales starting with the number 2, it’s called “Benford’s Law”. Here is the Wikipedia article, it is REALLY interesting stuff. Employers can use it to spot fake expense receipts!

http://en.wikipedia.org/wiki/Benford’s_law’s_law

dchomak
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OK, the cells are charged up to 4.20V and the head of the light with the driver in place is ready to go. This time all connections are soldered including the connections to the meter. The leads are 14 gauge and are soldered directly to the banana jacks inside. Also the wires to the cell pack are soldered and the connections to the driver are soldered. There are now NO banana plugs or alligator clips to introduce resistance because of less than perfect connections.
Cells sitting at 4.20V and the light is not yet turned on, 0.0A.

Now on high, 13.75A, 2.3A per emitter.

Siskiyou
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dchomak wrote:
Now on high, 13.75A, 2.3A per emitter.

Wow that is a lot of juice! So let me see if I got this right:

$23 Flashlight
$ 1 MOSFET
$ 5 Batteries
$29… Now that is one Value light! Wonder how many lumens/$?

UDO
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**Received mine today. Its my first fatty Smile If my multimeter is correct, it draws 7A on high and 2.7A on “low” from 4 freshly charged panasonic laptop pulls. The quality, look and feel is superb for the price.

ImA4Wheelr
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Thanks for the info RMM and dchomak.  So you take your readings before the shunt starts getting too hot.  Makes sense.

dchomak, Great info on the resistor, voltage, and Benford's law.   Looking forward to reading that Wiki you linked.  Thanks again.

dchomak
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Siskiyou wrote:
dchomak wrote:
Now on high, 13.75A, 2.3A per emitter.

Wow that is a lot of juice! So let me see if I got this right:

$23 Flashlight
$ 1 MOSFET
$ 5 Batteries
$29… Now that is one Value light! Wonder how many lumens/$?

Some here may wonder about the $5 Siskiyou is referring to. I mean how can 4 – Samsung 2800 mAh be only $5? In my case, and others, I have lucked out every step of the way on this one! The battery deal referred to is a NOS $10 laptop battery pack deal that he posted about here on BLF a couple of months ago. 8 Samsungs, new and in perfect condition. Turns out it is the perfect companion for this light, 2 sets of 4 cells. One in the light and the other set charged up ready to go. The deal has expired now but here is the link.

http://budgetlightforum.com/node/30138#node-30138

Another benefit of these cells is that they are meant to be “over charged” to 4.3V. I won’t normally be using them that way and neither will most others that picked up on this deal. But I thought I might as well go for it and see what they will push through the light at 4.3V, so I charged them up.

On high, 15.02A

On “low”

Notice that 1/10th of a volt more pushes another 1.25 Amps. The open circuit voltage is not what does that but rather the voltage while under load. I’m sure IMR’s would do even better, as they will not sag as much under load. I have some, but so far I have resisted trying them out in this light. My biggest fear is blowing the traces on the MCPCB

RMM
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Yes, the low resistance cells will do significantly more than that.  A single VTC4 or 20R will almost allow amps than four of those cells, for a little while at least.  Four VTC4/VTC5/20R/25R will do around 20A into three XM-L2s, I am guessing that with 6 XM-L2s 25A isn't out of the question with these cells, maybe even 30A. 

The nice thing is that you can use higher resistance cells to limit current.  The NCR18650B is a good example of this, great capacity but it will only do around 4A maximum direct drive.  

Mountain Electronics : batteries, Noctigon, and much more! What's new? 

blfdemigod
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What are the odds of ever finding some of these VTC4/VTC5/20R/25R in a laptop pull? That would be sweet! Didn't know they make that much difference in our flashlights versus they panny 3400!

My collection 2 Small

Disclosure:

ryansoh3
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Just wondering if we should make a new thread for modding this specific SRK?

BLF ≠ B-grade Flashlight Forum

 

wight
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blfdemigod wrote:

What are the odds of ever finding some of these VTC4/VTC5/20R/25R in a laptop pull? That would be sweet! Didn’t know they make that much difference in our flashlights versus they panny 3400!


Zero. They are not laptop cells, high drain cells are used in other applications such as power tool battery packs.

Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

jps
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ryansoh3 wrote:
Just wondering if we should make a new thread for modding this specific SRK?

Good idea! I ordered a Mosfet and low resistance silicone wires from Mtnelectronics.com to boost this new friend! Smile

phlowcus
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I don’t know if there is a better thread for this but I just wanted to let you know that DX finally shipped my order of three pairs of protected Sanyos (sku 121447) they had on sale at the same time as the Skyray of the OP.

They are back on sale but now at $11.99. They exchanged the pictures, too.

jps
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I just finished the mod of dchomak with the low resistant wires & mosfet I got from RMM (thanks guys!). Also did a tail spring mod with soldering lytze and put more thermal compound between star & pill.

As dchomak already mentioned, the driver is glued in the head and I also had to pound on the driver from the other side to disassemble. When desoldering the wires, I notice the red wire was connected to the L- on the driver. I didn’t remember whether it was connected to the + or – pole of the LED star, so I soldered the new wires + to + (red) and – to – (minus). The flashlight didn’t give a kick so I crossed the wires.

I tried to screw back the battery compartment and the SRK gave an intense bright hot flash so I thought I blew the LEDs to heaven J). In a startle response the batteries flew around the room :~ Didn’t smell bad though, so I picked up the batteries and screwed it on again.

The light started shining, so apparently it was default on. Well, in fact it was SHINING!! My goodness, this is a performance boost, I really felt a powerful hot beam shining on my hands. The body got also quite hot quickly so there must be a lot more Amps pumping around.

In my opinion, this DX SRK is a real BLF champion. Cheap, quite easy to mod, good quality and a powerful lumen king. Highly recommended!

hayhayday
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i ripped one of the traces trying to replace the mosfet. Anyone know of a replacement driver ?

ChibiM
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Still haven't received mine yet.

dchomak
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I had ordered 2, 1 each from DX and DX-US.

DX-US shipped on 4/1 and I received it 4/12
DX shipped on 4/2 and I have not yet received it as of 4/26.

I am looking forward to it so I can measure the “before” performance.

DX is now asking $36.65 for this light, what a nice deal we got.

UDO
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I was reading about warrior: http://budgetlightforum.com/node/22884 and I really liked some features like ramping brightnes and lock out. My SRK 6x xml2 has very high “low” around 40-50% of max current (a real low of around 20% would be more usefull for me at least). When I was trying lock out feature on SRK (btw it does work with just a small twist) I found out if I set it to low and twist it just before it looses contact, I am able to get very low brightnes (much below 100 lumen).

M4D M4X
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i think you just creating high resistance in the threads – maybe it warms up and sizzles there…

PLEASE NOTE
i do not work in "reviews, deals and codes" for the time being
maybe M4D M4X will return one day, but until then:

THANK YOU FOR YEARS OF YOUR SUPPORT AND FRIENDLY CONTACTS!

wight
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hayhayday wrote:
i ripped one of the traces trying to replace the mosfet. Anyone know of a replacement driver ?
If you can replace the FET I’m fairly confident that you can repair the trace. A jumper wire will be lower resistance than the trace is anyway.

Still fine, still on a break. One day I’ll catch up with you folks! previous wight catchup Wink
list of my drivers & variants (A17DD, FET+1 stuff, WIP stuff, etc)

ChibiM
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dchomak wrote:
Here are pics of the tear down.  With the tail cap off. First time I have seen one with all 4 screws installed.So I had to go at it from the other direction. After unscrewing the bezel, I used a sock (for the feet) over my hand to unsrew the reflector. I was very happy to see this, as other cheap SRK clones did not include this. This provides a good thermal path to the body of the light. Once I was able to get behind the reflector, I was able to pound out the driver from the back side. It took quite a lot of force to break it loose. The leads to the star are 24 gauge. !

got mine today...

Compared to my Supfire M6 (300 lux ceiling bounce, versus 220 of this Skyray King), I want to get this thing apart.

How can you get the reflector off, when the white led centering rings are still installed?

B42
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Well DX lied and is playing games again. This is twice I’ve ordered the SRK at a low price from DX and they then wait a while, then claim its out of stock, but have another light listed at a higher price that looks like the same thing. Of course the new listing requires more money before they ship. DX is a really crappy scammy site! Randomly some people actually get the light to increase interest, while others get the scam setup message for more money to ship out I guess.

RMM
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Hate to say it guys, but they are messing with me as well.  I ordered a lot of these (over $1,000 worth) in two separate orders on March 31st and April 1st from the US Direct site.  About a week later they added tracking information, which now more than a month later is still invalid; that's six invalid numbers after 30+ days.  I have tried contacting them multiple times with no response.  I opened a PayPal dispute and waited about five days, no response.  I escalated to a claim more than a week ago, no response.  

They have been holding onto more than $1,000 for over 45 days and won't answer an e-mail, message, or a claim.  What's worse is that they added tracking information when it's obvious they never shipped anything.  This tells me that they know they screwed up on the pricing but didn't want to admit to it, so they faked it to buy some more time.  I don't know about you, but I don't like giving businesses $1,000+ 45 day interest free loans (when it wasn't part of the initial bargain,) especially when they act like this.  I am convinced that if I didn't file a PayPal dispute they would keep the money and never say a word.

I don't think that everyone will have this sort of problem dealing with these guys, but I've given them a few weeks to make things right and they haven't said a word to me so far throughout all of this.  I've ordered from them before without any issues, starting about a year ago, but this is beyond the pale.  

Mountain Electronics : batteries, Noctigon, and much more! What's new? 

phlowcus
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RMM wrote:

[…]for over 45 days and won’t answer an e-mail, message, or a claim[…]  

That’s really bad! They don’t use email anyways but I take it with message you mean a DX ticket?

M4D M4X
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i had also some troubles with my last order…

fortunately a lot less money Wink

PLEASE NOTE
i do not work in "reviews, deals and codes" for the time being
maybe M4D M4X will return one day, but until then:

THANK YOU FOR YEARS OF YOUR SUPPORT AND FRIENDLY CONTACTS!

cia212
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RMM wrote:

I opened a PayPal dispute and waited about five days, no response.  I escalated to a claim more than a week ago, no response.  

They have been holding onto more than $1,000 for over 45 days and won’t answer an e-mail, message, or a claim.  What’s worse is that they added tracking information when it’s obvious they never shipped anything.


Did you call Paypal? I called and Paypal forced a refund in less than a day.
Pulsar13
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Refund isn’t the main point now, it’s the way DX is behaving and stalling by saying it was shipped when it is not. The shipment is US to US, it should not still be invisible after 30 days. No idea what happens after the 45 days PP protection window.

I don’t know about you guys, but what’s happening to RMM is pretty close to an actual scam IMO.

cia212
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Pulsar13 wrote:
Refund isn’t the main point now, it’s the way DX is behaving and stalling by saying it was shipped when it is not. The shipment is US to US, it should not still be invisible after 30 days.

DX doesn’t ship anything US to US.

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