On Fri, 03 Dec 2010 18:44:24 -0600, " email@example.com"
I don't know who this Claire is - might well be a moron.
This from an expert:
Traditional tin-lead materials are not compatible with lead-free
device finishes. Because proper reflow for lead-free materials can
only be achieved with higher temperatures, attempting to process
lead-free terminated devices in 183?C tin-lead conditions leads to
incomplete wetting and the related issues of voiding and opens.
Doug Dixon, Global Marketing Director
Mr. Dixon has been in the electronics field for over twenty years and
is the Global Marketing Director with the electronics group of Henkel.
Prior to joining Henkel, he worked for Raytheon, Camalot Systems, and
I'll take his word over someone ( a usenet engineer) who fudges his ID
And another expert agrees:
Many of the components manufactured in the last few years have been
lead free, especially surface mount chip components as they are Tin
Can you solder these with 60/40 tin/lead solders, the answer is yes
and millions of solder joint have been soldered this way for years.
The problem however is some of the Lead-Free component plated RoHS
components have a SAC alloy for a lead coating and this is the issue.
The 60/40 alloy will not be hot enough to melt the SAC alloy to create
a sound joint. Yes, many papers have been are being published stating
that this will work, but keep in mind the thermal profile and the
length of time the solder joint needs to be above the reflow
temperature to all complete dissolution of the Tin/Lead into the SAC
alloy coating or solder balls on the components. This is much
different than what was used to the low temperature Tin/Lead alloys
and dwell times above the reflow temperature is going to have to
increase to create a sound solder joint.
Leo Lambert, Vice President, Technical Director
At EPTAC Corporation, Mr. Lambert oversees content of course
offerings, IPC Certification programs and provides customers with
expert consultation in electronics manufacturing, including RoHS/WEEE
and lead free issues. Leo is also the IPC General Chairman for the
Assembly/Joining Process Committee.
Again, I'll take the word of an acknowleged expert in the field over
that of the unknown usenet engineer.
If you are 100% certain your RoHS compliant components have tin
coating, you CAN use leaded solder.
If you are just ASSuming all RoHS compliant components have tin coated
leads, you are treading on extremely thin ice.
I have stated that using leaded solder with RoHS compliant components
is "not best practice" and can lead to product failures.
I'm not saying you can't get away with it some or most of the time -
I'm saying it is not correct, and it is wrong and dangerous to say it
is "safe" or "proper" to solder RoHS compliant components with regular
Recommending it is not being responsible, without at least adding the
possibilities of the "gotchas" which are well documented and
recognized by the experts, and which I have provided cites for.