Well, you are both right and wrong. Sorry, The correct way to remove an SMT component is with the right tools. Most of the accepted makers of SMT soldering and unsoldering equipment have gone to great lengths in minimalizing the undesirable effects of over heating by having available tips that match the size of the component like a saddle. The tip touches both the ends of the component and the solder bridge to loosen the part and with a vacuum pick either in the wand or standing by to suck the part of the PCB. Honestly it is the most desirable way for minimum impact to the PCB trace. In a off site situation I have done the leap frog on both ends and with a dental pick lifted one side then with tweezers hold the part and unsolder the offending side. The absolute worst why is to try and pry the part up while overheating one end. Ugly. Sorry, guys the had to give my two bits worth. Buy the way the right tips are far less expensive than a damaged PCB.
Mel, K6KBE Mel --- On Thu, 4/19/12, Alan Bloom <[email protected]> wrote: From: Alan Bloom <[email protected]> Subject: Re: [Elecraft] SMT and the K3 - Nerves To: "Ron D'Eau Claire" <[email protected]> Cc: "'Elecraft Discussion List'" <[email protected]> Date: Thursday, April 19, 2012, 2:58 PM On Thu, 2012-04-19 at 14:23 -0700, Ron D'Eau Claire wrote: > I have removed hundreds of two-terminal SMDs both by cutting them in half or > by unsoldering one end at a time and lifting the part with never any damage > to the pcb. On most two-terminal SMD parts (resistors, capacitors, etc.), the solder terminal on each end extends on both sides (top and bottom). So the way I generally remove them is to tin the top of each contact with a little solder and then lay the soldering iron tip across the top of the entire part so that it heats both ends at the same time. Once the solder melts, you can push the part off the pads with a toothpick, Exacto knife, whatever. > Good light and your favorite magnifiers (if needed) to see clearly are > essential. In my experience, being able to see the darn thing clearly is really the key to successful SMT work. I have a binocular microscope with built in light that I bought brand new for about $300. Whatever you use, make sure to have a bright light, and some form of magnification is very useful for those of us with middle-aged (or greater) eyes. Alan N1AL ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
