It's not just a matter of using different solder. The new solders have a higher melting point and hence need a hotter soldering iron; typical 50W WECP/WTCP won't do because, while they have the temperature, they lack capacity at those high temperature - they can't heat the joint quickly enough. You'll need the newer 80W soldering stations or risk cold joints. There's a reason the older 50W stations are available so cheaply these days.
The new soldering iron comes with a tip that has a thicker ironized coat as the new solders corrode tips a lot faster. Forget about using a wet sponge. Because of the higher temperature, wiping on a wet sponge would cause too big a temperature jump and hence you'll need to wipe on a special tool. Note that the routine differs: wipe, wet, solder, wipe, wet, back to holder. The new tools together cost about half a K2. Note that it's important not to contaminate your RoHS-tools with your older tools: small pieces of lead will change the composition of the alloy, greatly reducing reliability. The higher melting temperature means that un-doing a component is more difficult, with a higher chance of PCB damage, certainly with less experienced builders (not everyone has a space qualification, I don't). Because the new solder's wetting characteristics are a lot worse, I'm concerned about stripping and wetting toroids with lead-free solder. Wel all know that not everybody is fully successful wetting and stripping toroids as-is. Just ask Gary, who, I'm sure, is not looking forward to higher warranty claim percentages because of doubtful toroid stripping with lead-free solders. Note that some new alloys have a tendency to form bridges (shorts) after a number of years. Not a problem for a toy that gets discarded after 2 years, but big problem for a tranceiver which typically has a lifetime of 20-30 years. We all see the cheerful messages from people who "haven't soldered in over 20 years" or so, and are now getting back to kitting. Lead-free soldering is a lot less forgiving to new, but unexperienced builders as it is intended to be used in tightly controlled circumstances. (we all know that with a WTCP and leaded solder it's difficult to "go wrong"). While I realize that it's less environmentally friendly, I think that using leaded solder, for a large percentage of the building population, will have enough advantages that we should make use of the exception to the rules that was given to us "kit-ters". I agree with Elecraft that the change should not be made lightly, and not just by using different solder. They suffer the consequences of a lower yield percentage, and I don't think anyone would want that. 73, Geert Jan PE1HZG K2#1981, not RoHS-compliant, sorry! _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
