FS: Key Chain CR2 Build Kit! - SCHWEET!

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Your getting nice power out of that diode!

Thanks for your input on the assembly Dark...

I would say that the hardest part is setting the driver current. (which is no big deal) As with any FlexDrive build. But in this build, you must set the driver current before you install it. Soldering is the same as any build, but you must have a test load to set the current before driver installation.

Still possible to install the driver first, and have thin wires out the front to put the module/diode in last if you want, but easier to install the module/diode first, and then the driver. (IMO) Either way, you must set current first, because once the driver is installed, you cannot adjust the pot without taking the driver out of the heatsink/pill.

I really think the 1st post 'picture tutorial' is very good for assembly help. Shows the orientation of the FlexDrive as well...
Jay

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Very nice tut and build. wow. hopefully one day I can build like this.

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Thanks...


Anybody that can set a FlexDrive with a test load can do this build. You just have to have fine wire, heat shrink tubing, and a desire!
Jay

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Jay --

Nice build and kit. I like to see members realizing that long duty cycles on these "light sabers" isnt needed. ON, Bang and off for a while is sometimes more impressive.

Mike

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Thanks Mike!

I've always had a habit of using a 1 minute or so duty cycle...

But just for the record, this little Key Chain CR2 host is pretty solid. The metal on the host is nice and thick. With the heatsink making good contact to the host, in effect, the entire host becomes the heatsink.

So it is really not too bad at all for heatsinking, for the size of it...
Jay

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Oh man, I can't wait to get my hands on one of these >

Jay --

I've been fgone for quite a while and missed a lot.
Do you happen to know where everyone gets these cheap 8x diodes?

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Kendall is one person that has the BDR-S03 sleds (HighTechDealZ), but some are getting mixed results. So just know that they have not been fully put to the test yet.

But I have seen some who have got 8X power from them. Some have also killed them at 300mA's, so if you go with one, I would just stay at the 250ish area... (just an opinion)

The Pioneer BDR-203 diode, which must be harvested from that drive, is for sure proving to be very consistent. Take a look at the compiled graph and list of known 8X owners that FrancoRob is updating. He also lists other information, like host/driver/current/lens/power...
http://laserpointerforums.com/f38/8x-br-diodes-42806.html

About the Key Chain CR2's, I have them on hand! Just let me know...

Re: FS: Key Chain CR2 Kit! - SCHWEET!

jayrob said:

If a GGW 6X is built properly, I would think it would last a long time at 190mA's. I have several at that power range. But I also have a habit of using a 1 minute duty cycle.
Jay

Click to expand...

True dat... However i don't use ANY kind of duty cycle and i'm getting the result of YEARS of normal pointer use from GGWs at 190-200mA (which is where most of the 60 i built were set to). EDIT: Ooops, i forgot this is a Keychain build. In such i do use a duty cycle as well - i turn it off, when i feel it becoming too warm on the outside..


BUT! I have noticed that low efficiency GGWs can die at those same (or even lower) currents within a few hours, while putting out as little as 160-170mW after a plastic lens.


iknitsteel: Do you know what the power of the doomed diode was?!?



This is the reason for my careful diode selection process. I only use diodes that produce a minimum of 180mW at 200mA during pretesting, don't set them above 200mA, and reach higher powers with higher efficiencies...


Unfortunatelly, as a result, i am getting stuck with more and more low efficiency GGW diodes which peak as low as 160, 150 or in this one case even as low as 138mW at 200mA (after a plastic lens)!

This is not a new occurence, all except for 10 of my GGW diodes come from the very first two GGW batches ever sold, and the efficiency spread was always the same (i heard some people complaining of there being bad GGWs latelly - that's not true, they were always there!)...



I need to type the PIV data into Excel, make plots and posts some interesting statistics and findings, but this is starting to look more and more like a daunting task to me with the numbers of diodes i went through by now, with each diode having 20 data points for Power, Currrent AND Voltage (10mA resolution) as well as relative wavelength and amount of spontaneous emissions remarks.... :undecided:


But it needs to be done... People should know what the reality looks like.

It was the same with PHRs. With those i was posting more limited "batch testing data" (just a couple of data points) for them as i slowly went through ~100, but they varied just as much in efficiency as the GGWs do, as they did in toughness....


One interesting thing i noticed is, that some (not all but some) of the "low efficiency" GGWs actually have a MUCH lower Vf and a higher threshold current! If i didn't know what they were, i could easily have judged them to be a higher power diode! Those with the lower Vf they COULD actually have a higher efficiency, or at least similar to the good ones.

This is one theory i have yet to test.... I'll take a low efficiency GGW with a high Vf and a "low efficiency" GGW with a low Vf, and cycle them side by side. Can't do much else with them anyways.... :undecided:


But there is a small (VERY SMALL) possibility that the Vf could have an impact!

Re: FS: Key Chain CR2 Kit! - SCHWEET!

Hmmm... that's very interesting Igor.

I have only been through maybe 12 or 15 GGW's, but I have never had any that were really low output like that.

Only about 180mW' At 190mA's (AixiZ acrylic) is about the lowest. But some were much higher efficiency!

Just out of curiosity, since you go through so many diodes. May I ask what method you use for removing the ribbon?

I have a theory that some diodes get damaged (or weakened) from using heat to remove the ribbon cable. But I have no way of proving this. Except that I have always had very consistent results with most all diodes, in clipping the pins clean with fine snips...

P.S. iknitsteel said he was getting some kind of short in the build (said it was 'flickering'), so I would guess that this was the reason the diode died so fast...

Re: FS: Key Chain CR2 Kit! - SCHWEET!

jayrob said:

Hmmm... that's very interesting Igor.

I have only been through maybe 12 or 15 GGW's, but I have never had any that were really low output like that.

Only about 180mW' At 190mA's (AixiZ acrylic) is about the lowest. But some were much higher efficiency!

Click to expand...

Yes, see, but i know where those diodes came from, and among them were many v3's (arbitrary numbering system we made up with Dave to separate the three different sled versions). Unfortunatelly, there were no v3's in later batches... Only v2's are left..

The v3's were the super- and mega-freaks - without exception, every single one peaked between 215-236mW after plastics. They had a pot that regulates the current set way lower than v2 sleds! The v1's, i don't remember, i should check my notebook. But i think they were also good. The v2's on the other hand were the most numerous... At least in my case.. I don't know what kind of mix you got at that time, but maybe you were lucky. Because the v2's are all over the place.. There are freaks and super-freaks among them, many "normals", like my first GGW was, and then also many lower efficiency ones.

But the datasheets in their slope efficiency Min. Typ. and Max. ratings show variations even higher than what i'm seeing here! So technically speaking, the diodes still are up to specs! Even the lowest efficiency ones!


With small samples, statistical anomalies appear quite often.
But with a big enough sample you always get the same picture.

jayrob said:

Just out of curiosity, since you go through so many diodes. May I ask what method you use for removing the ribbon?

I have a theory that some diodes get damaged (or weakened) from using heat to remove the ribbon cable. But I have no way of proving this. Except that I have always had very consistent results with most all diodes, in clipping the pins clean with fine snips...

Click to expand...

We discussed this once before, when i was posting PHR efficiency data..
I told you what tools i use to remove the PCB/ribbon thingy back then.. :yh:


Check out the attachment..

This is how i do it:
- I set the digital soldering station to 330°C, as per the diode manufacturer's specifications (3s of soldering allowed at 330°C, 1.5mm from the base of the diode - say the datasheets).
- While the soldering iron is warming up, I cut as much of the PCB or ribbon off around the pins and between them with the diagonal cutting pliars (on the left in the attachment) as is possible, without bending the pins... I try to separate the ribbon pieces from each other, so that each pin has a tiny piece left over.
- I remove the remainder of the ribbon downwards by separating it from the solder blob with a fresh surgical scalpel (on the right of the attachment), and in some cases i have to remove some solder with the scalpel as well, cutting between the solder and the pin to release the ribbon from the pin if it won't separate the usual way...
- In the end i just swipe the leg quickly to get the remaining solder off. This swipe takes less than a second and removes all solder. The diode is in a heatsink from the start... The previously separated ribbon pieces then just fall off the pins by themselves.
- During this entire time (and whenever i'm handling diodes obviously), both me and the soldering station are grounded.


Trust me, after almost 12 years of working with electronics, i should slowly know how to solder safelly..

But when it comes to expensive diodes, i am infinitelly more careful, than when i'm soldering ICs to PCBs for example...



Wait, wait! The pre-testing is done in a different setup! There i don't even remove the ribbon! I just solder to it! That's where i got those ridiculous numers from! Before the ribbon was even removed. But those ultra lows are luckily rare, however even the 200mA/170mW ones can die after only a few hours of use... (That's why 180mW is my lower limit - they already fall under the "normal-efficiency" category...)


The above procedure was describing the after selection stage - when i'm cleaning the diode assigned to a laser, already installed in a Heatsink/Module, so i could solder it to the driver... I determine diode efficiencies long before removing the ribbon.


EDIT: Oh, and i have two of those diagonal cutting pliars (is that what they are called?) One is for rough work, where it gets damaged, the other is for undressing diodes ONLY, so it doesn't lose it's edge... The sharp one is marked with a thin piece of blue electric tape on the inside of the left handle. You can even see it slightly in the photo...


EDIT EDIT: I have a theory on why some diodes have such a low efficiency. These are QC-Reject sleds. Some get rejected due to broken parts, lenses etc. But others MIGHT just get rejected due to the diode not being up to specs - not providing enough power to do the burning at the desired speed...

Maybe a part of the rejects are rejected for this reason, and they end up on our forum...


But i've heard from several people complaining that the GGWs are sometimes way low in efficiency by now. People, who just buy one or two, can either get very lucky or very unlucky. It's completelly random. I bought 78 diodes in two purchases and now 10 more, and i get to see all types. Luckily the really bad ones are in a minority... But it still bugs me!


I really need to test the Vf theory! Maybe i'm onto something there, and if so, those diodes could still be used. Even for high powers! Theoretically, they could even be tougher, by some random fluke during die growth... But this is just something i want to test one day, so at least i put the "weak" ones to some use...

Re: FS: Key Chain CR2 Kit! - SCHWEET!

I remember we did discuss it before, but I forgot the details...

It's because you use a combination of 'snips' and just a little heat, one pin at a time.

I enjoy reading your scientific explanations of everything!

About your saying (about the lower efficiency diodes), that 'theoretically, they could even be tougher, by some random fluke during die growth', wasn't your very first GGW 6X a lower efficiency diode? I seem to remember reading that. And it was a really tough diode right?

Re: FS: Key Chain CR2 Kit! - SCHWEET!

What host did you used for it exactly?

bigG

Re: FS: Key Chain CR2 Kit! - SCHWEET!

jayrob said:

About your saying (about the lower efficiency diodes), that 'theoretically, they could even be tougher, by some random fluke during die growth', wasn't your very first GGW 6X a lower efficiency diode? I seem to remember reading that. And it was a really tough diode right?

Click to expand...

My first GGW WAS a REALLY TOUGH diode, yes! It just didn't want to die, no matter how much torture i put it through.

It survived approximatelly 5 "normal-user years" in the year it suffered in my hands...


But it was not a low efficiency, it was what i now call a "good-normal"...
It did 193mW at 199mA...

Then it degraded to 185mW over the course of a year's worth of abuse, and in the end, i raised the current, pushing it to ~260mW after medium glass. That finally killed it in the end (but still not immediatelly).


I may have said once that it was a lower efficiency, when i stumbled onto a batch of "v3" GGWs, but by now i am HAPPY when i find diodes like that one!



The "low efficiency" GGWs potentially being tougher - i meant the ones with higher threshold currents, and lower Vf's... They seem almost as if they were higher power diodes if i only had these two factors to judge from...

And their lower Vf makes up for the lower slope efficiency, when it comes to actual efficiency - Pin vs. Pout...


Those are the diodes i would like to test, to see if they are any good.
I already killed a few low efficiency GGWs (actual low efficiency - low slope efficiency and high Vf). Now i need to torture some with "low efficiency" (low slope efficiency BUT also low Vf's!) to see if there is a difference....

Re: FS: Key Chain CR2 Kit! - SCHWEET!

I think we should all send any new diodes to you Igor! (the scientist)




bigG, was that question directed to me? If so, are you asking about my 8X build? If so, I have it in a Pocket Mini host/FlexDrive @ 292mA's... 375mW's. (405-G-1)

Mine is a little lower in efficiency compared to some of the other BDR-203's.

Re: FS: Key Chain CR2 Kit! - SCHWEET!

jayrob said:

I think we should all send any new diodes to you Igor! (the scientist)

Click to expand...

Haha, i definitelly wouldn't mind.. :angel:

I mean, i did make all those torturing and analyzing devices for a reason..

Altho at that moment, the main reason was to make my work go faster, since plotting diodes using a regular driver is a bitch! It takes two DMMs, a mess of wires and aligator clips covering the table, and a driver with a tiny pot that requires nerves of steel to adjust, while the diode is running!

That's why i decided to make a single device to replace all that, with more accurate and completelly linear current control (interestingly enough, the same thing could be achieved with a cheap widely available driver and a simple two pot arrangement if anyone is interested.. maybe i should post the plans)


It was actually a fun little project. I still haven't gathered the nerves (nor found the time) to install those aluminum plates tho.

Re: FS: Key Chain CR2 Kit! - SCHWEET!

sorry, yes it was directed to you, jayrob.
i only wanted to know where u got this host for the key chain cr2 build
thanks
bigG