Laser Diode Pin Fragility Assistance

Hello everyone, I'm just here to ask a question that I have yet to be given advice on. You see, I've been noticing that the positive pin on two of my laser diodes have broken after a bit of use. Now, I know not to solder for too long on the diode because of the intense heat, but I'm guessing that it is my poor solder job that is allowing my diode pins to break. My last one, a 3.8mm diode's positive broke off after a few days, but I managed to successfully put the pin back on after searching the forums and looking at Daedal's advice. I should also mention that I am soldering the pins to wires for fear of actually getting the soldering iron on the diode repeatedly. Does anyone have any advice on keeping the diode pins from breaking off? Also, another quick question, but will this heatsink work for a A140 445nm diode at a voltage of 9v and 1 amp with a duty cycle of 10 seconds on and at least 20 seconds off? Amazon.com : AixiZ aluminum mount and heat sink for 12mm modules : Other Products : Everything Else
Thanks everyone, and I'm sorry if I'm posting this in the wrong section.

A bit of heat shrink always helps me. And yes, that heat sync should be fine for that application.

Pictures or a better explanation of how they were put together would help, most people only break the pins by accidently twisting the wires when assembling the laser.

Alan

Heatshrink would help, or you could get a diode socket, so you dont have to solder right to the diode pins.also keep in mind, laser diodes are tiny and frsgile- the pins are even smaller.

Wow, thanks. I didn't even know about diode sockets. That's quite helpful. And to Pi, sorry for the lack of pictures, if you want, I will put some up, but I did notice that the wires were just a bit twisted around the pins. Also, I haven't really used heatshrink at all, so is there a certain size or type of heatshrink I should use? Sorry if I'm asking a stupid question, I've just gone by with electrical tape, which I now understand cannot be used for everything.

You can buy the heat shrink online anyplace selling electronics or on Amazon or its sold at your local RadioShack store, if your in the US. For lasers you will mostly need the smallest size but if you do other electronics projects you should buy a package of assorted sizes. Electrical tape can sometimes come loose if it gets too hot too many times.

Alan

Dont worry about soldering and desoldering to the pins. The main issue is excessive heat ie soldering for too long at a time. Just touch (< 1 sec) the pins with some fresh solder and make sure the pins are tinned - let it cool. Take a pre-tinned wire and hold it just above the pin 1 mm, or so, and touch the iron to it. When the solder on the wire is liquid move the iron and wire together down onto the pin - it will bond instantly. The whole pin pre-tining and connecting processes take less than a second. Perhaps practice on an old diode first. You need a good connection between your power leads and the diode pins for your laser to work properly and reliably and a bad connection could end up killing your diode! Do it properly!

As others have mentioned heat shrink is a good way to strengthen the link and electrically isolate the connections, but make sure the solder joint has been made correctly in the first place.

One issue to avoid is too much solder; if you have a big blob on the pins this can take time to cool and transfer too much heat to the diode. Also make sure you have taken proper ESD precautions...

Good luck and dont be too afraid! :beer:

Thanks grainde! I actually do have a few old, useless infrared diodes that I could practice on. Now I've been looking at the diode sockets and am wondering if that will in anyway hinder my use of the aforementioned heatsink. What do you guys think? Also, any recommended places to buy the sockets? Everywhere I'm looking they are ridiculously expensive.

AixiZ has some cheap sockets but only for 5.6mm diodes:

http://www.aixiz.com/store/product_info.php/products_id/454

http://www.aixiz.com/store/product_info.php/products_id/447

Alan

I can't thank all of you enough, and I have just one more question as of right now. Are there any good, cheap hosts that would work with the diode socket? Or perhaps a host that would fit an Aixiz module? I would prefer the pen/flashlight style host, but if it is a lab-styled one, I'm fine with that too.

They will all fit an Aixiz module, its the heat sink in the host that has to fit an Aixiz module. There are some slight exceptions where a full length module wont fit unless you use a drilled pill. Weather you use a round driver in the pill or a rectangular driver directly attached to the diode and then a battery contact board can sometimes make a difference what fits. You need to read some build threads and learn more about the parts and what works together.

Alan

Will do. Thanks again.