Thread: awesome led lenser copy

We are talking the same animal. Yes you disassemble it and take out the while circuit board at the bottom. I hold the board in wooden 'soft jaws' I made for a small vice and apply heat to the back of the board. When it is hot enough I place the LED on the pad and line it up. The white stuff on top of the board is a solder mask and solder won't stick to it. You do not need to add more solder, normally I'll remove a little.

Originally Posted by gadgetman

We are talking the same animal. Yes you disassemble it and take out the while circuit board at the bottom..........................

Again, Ahhhhhhhhhhh.........Thank You

If I understand you, the white "washer" looking device in cree3.jpg, pulls/ screws/ levers out to give access for removal of the PCB below?

Originally Posted by Kiwi Sapper

Again, Ahhhhhhhhhhh.........Thank You

If I understand you, the white "washer" looking device in cree3.jpg, pulls/ screws/ levers out to give access for removal of the PCB below?

Yes it is an aluminium circuit board/heatsink. They come in various shapes and sizes. Often there is also a nylon spacer in there as well.

Ahhhhhhhhhhh has now been superseded by " Gosh, Golly"

The washer was a spacer and I see now that what I thought was one sealed unit is just an enormous heat sink. Which obviously didn't work in my unit :>(

My thanks and I will try that today. My only immediate problem is in establishing the = ve and + ve as theere is no black triangle on the emitter apparent. By comparing the solder marks on the PCB to to those on the reverse of the emitter, I believe that the _ve strip is the strip nearest the 3 incoming wires I can see leading into the array inside the emitter.
Well, I can only get it wrong once :>)

Thanks again.

Well, that did go well and the -ve was on the 3 wire side.

QUESTION.................When you say,"...I do it all the time." is that because they are:

a...detaching all the time? or
b... failing and requiring replacement all the time? or
c... you are upgrading the emitter?



and if B where are replacements sourced?

Once again my thanks, especially for the Youtube link
which really gave me confidence.

D - All of the above

I get them from DX and AliExpress. Often they are not available on the right board so I do the old switcheroo.

You may want to add some heat sink compound/silicon grease to the back of the board when you put it back together.

Originally Posted by gadgetman

D ....................
You may want to add some heat sink compound/silicon grease to the back of the board when you put it back together.

Good point, I will do that.

I did some Googling on the Cree operating voltage and it seemed to be 3 to 3.7 v. This caused me to check the power they were getting and I attached a multimeter to the cable connecting to the PCB and found I was getting 4.06v.. I had anticipated that the two 18650 Li-ion batteries in parallel would have been reduced to 3.7v by the "system," but no. I imagine I am going to burn out the emitters well before their stated life and that the excess heat generated as a result of the high voltage would have contributed to the emitter detaching.

I may try leaving the batteries, which are being charged in their correct charge unit, for a few week or so after charging to see if the voltage drops down to an acceptable level. Not sure why if they are rated at 3.7v they end up at 4.06v. shudder.

Is this an action you follow?

The batteries fully charged should be 4.2V and drop down to about 2.7V when discharged. 3.7V is a rough nominated mean. The circuit board will regulate the voltage and current to the LED and would need to be measured with the LED in place providing a load to get numbers of any use. They normally provide a defined current and the LED provides the voltage.

Originally Posted by gadgetman

....................voltage and current to the LED and would need to be measured with the LED in place providing a load to get numbers of any use. ................

Ahhh. Another good point.

I have ordered the heat sink compound which I will apply and also 4 replacement emitters in case it all turns to custard. :>)

As with the lemon, I will just have to suck it and see, at least now, thanks to you, I can remedy a surfeit of custard.

If you want you can extend the slot that the focus knob moves in with a file to really focus the beam to a nice projection of the emitter. Gives a bit more reach with the light.

Originally Posted by gadgetman

If you want you can extend the slot that the focus knob moves in with a file to really focus the beam to a nice projection of the emitter. Gives a bit more reach with the light.

I did wonder how units with a "focus" option, functioned as neither of mine have that ability. But as they were purchased for lighting areas being serviced whilst underneath an electric tram, all that is required for that activity, is a "floodlight" aspect. Anything further reaching than that and I suspect I would find my arms were not long enough to reach. :>)

However, should I end up with an adjustable unit in the future, I will remember with appreciation your hint.

you two need to get a room lol

Ahh that was April, Muzz - the post-coital cigarette has been well and truly smoked by now

What does that make us non techno types who were following the dialogue? Led voyeurs?