Techniques to recover electronic components and test them before re-use - Page 1
Forum section: electronics / general

author: Norm Folkers
author_rank: Newbie
timestamp: March 25, 2012, 02:43:56 am
content: Hi,I'm new to this group but have enjoyed viewing almost all of the video blogs. Thanks.I've been a big iron IT guy all my life and have just recently "discovered" the wide open possibilities of microcontrollers and how they can compliment and improve my other hoby of astronomy and telescope making, especially making the optics. I'm currently building a remotely controlled observatory, I know, it's been done many times before but I like to do it my wayI also get old PCs and periperals donated to me by friends all the time. The latest, a legal sized, never used (NIB), flatbed scanner. Usually they still work after just a bit of repair or adjustment. But much of the stuff I take apart for the mechanical componets. The electronics usually just got saved for a time, a year or two, and then also got carted off to be recycled.I feel I now have some knowledge to make use of some of these components, switches, LEDs, resistors, capcitors, etc. But my techniques for disassembly are woefully inadequate.I would like to see a video or a Forum discussion on techniques on how to recover, and test recovered components. With any ceavaets on what techniques will likely destroy a component. I feel that this would be a great way to reduce component costs and also repurpose perfectly good components.NormPS I guess 42 is the answer to everything! (Hitchhiker's guide to the Galaxy)

author: Rerouter
author_rank: Super Contributor
timestamp: March 25, 2012, 03:43:00 am
content: depends on whether or not they are through hole or smd, with smd you get a hot air gun and you can ususally watch them magically rain free from the board with little effort, but are harder to test,if its through hole, then it comes down to being good with a piece of desolder braid, or chip-quick solder, so you can easily lift out the components, and i will say, chip-quick wins by a mile for large dip packages,as for testing, it comes down to the complexity of the parts, for through hole and dip, a multimeter and a breadboard would cover 90+ % of the stuff, however for smd stuff, short of what you can do with a multimeter i dont have a clue,

author: SeanB
author_rank: Super Contributor
timestamp: March 25, 2012, 09:55:51 am
content: If through hole and not clinched use a gas torch to melt it all at once and then bang the board against a box. A little messy, but removes a lot of components at once, especially the bigger ones. Use outdoors of course. Works on SMD devices as well, but you will have a hard time finding them afterwards.

author: Rerouter
author_rank: Super Contributor
timestamp: March 25, 2012, 09:58:53 am
content: definatly would not reccomend a gas torch, burns and kills most of the chips, and any electro caps will likely start leaking,

author: T4P
author_rank: Super Contributor
timestamp: March 25, 2012, 10:26:09 am
content: I just test using breadboard for IC's or open leaded testing for others .I pull 'dem out using a big arse solder sucker and needle nose pliers/clamp pliers ( those flat toothy adjustable things )

author: SeanB
author_rank: Super Contributor
timestamp: March 25, 2012, 10:38:58 am
content: Quote from: Rerouter on March 25, 2012, 09:58:53 amI was not sugessting cooking the parts. Just toast a small area until solder is seen to melt, then tap against box. Repeat for next area until board is mostly clear, then you can desolder the rest and recover the stuff from the box.

author: saturation
author_rank: Super Contributor
timestamp: March 26, 2012, 11:12:28 pm
content: I used to use a soldering iron, sucker and wick for years, but I found in most cases a hot air workstation does the same faster, like the 858D that Dave reviewed, and can do without the solder sucker or wick. It provides more BTUs than an iron, control heat and air flow, focus it, even heat multiple leads simultaneously. SMD pop off in under in seconds.All salvaged parts are then given some performance tests before being put into a parts bin.

author: jackbob
author_rank: Regular Contributor
timestamp: March 26, 2012, 11:30:32 pm
content: Just buy the components you need. A typical ic costs what 25 cents maybe a dollar for specialized ones. then you dont have to go throught the pain of testing them and hoping you didnt damage them while removing them (ic's can be a pain to remove). Plus you get the whole lead and not some cut or bent ones. Now large discrete components such as capacitors, large fets, transformers, large diodes and such; ya they are much easier and very well worth recovering most of the time. These are also the more expensive components usually, a good size and quality cap for power can run 5 bucks a piece and some igbt's will run you as much as 10 dollars each some even much more! To remove these i use a solder sucker then solder braid to clean whats left. If your looking to score microcontrollers usually you dont find the ones your looking for and its not uncommon for uc's to be locked to prevent people from changing or stealing the code on the chip.