I hope we didn't drive you away with the answers, Rob! Keep in mind that there is NOTHING wrong with the quality and durability of joints that lead-free solder makes. It's great stuff that works very well.
For hand work there are two important issues that recommend against its use: 1) Lead-free solder melts at a higher temperature than leaded solder. Higher temperatures mean it's easier to lift a trace or damage a solder pad if you change a part. Of course, a higher iron temperature is needed during assembly too. Many builders are already skittish about using a high enough temperature iron already, so the idea of pushing the temperature higher isn't very welcome. 2) At least some lead-free solders cool to a nice, dull matte finish: exactly what we've been taught to recognize as a 'cold solder' joint that is not reliable. It can be very hard to tell a good joint from a bad joint. It simply doesn't seem to make sense to buy into those issues when leaded solder is readily available and has a century-long history of doing an excellent job in electronic gear. While we're on the subject of solder once again, let me repeat an important slightly off-topic warning about fluxes! AVOID WATER SOLUBLE FLUXES LIKE THE PLAGUE! They are a plague that will ruin your rig. "Water soluble" sounds great. A little water and they're gone. No rosin mess. But they are a disaster for hand work outside of a special property: The water-soluble flux remains corrosive at room temperature, just like acid-core plumber's solder that we've all learned to avoid in electronics. (Rosin is inert below the temperature at which solder melts.) Joints soldered with the water soluble flux must be "power washed" in a special machine to remove all traces of the flux immediately after soldering. Failure to do so will result in your rig becoming intermittent in a few months as the flux literally eats its way through the traces on the boards. The boards will be a total loss. Ron AC7AC -----Original Message----- Ok, The point is well taken. I will use only my standard Pb/Sn for the K2 and save the Pb-free stuff for a few specialty projects. Thanks for your input. (This was my first question to the group - thanks for your input). 73 Rob KC6ROC _______________________________________________ _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
