On Wed, Nov 30, 2005 at 10:23:37AM -0800, joeft wrote:
> 
> I have found similar info as what Steve has noted.  Many vendors are letting 
> their parts automatically "roll over" to lead free compliant versions.  This 
> means that if you manufacture something now (during the transition) you will 
> have a mix 
> of RoHS and non-RoHS compliant parts.  Some will solder better than others 
> depending on your assembly shop's process.  And you might find this leads to 
> extra documentation overhead should someone want to know what your compliance 
> status is down the road.
> 
> Lead free solders will be mostly tin with a small amount of other metals 
> (usually bot not always silver), and they will indeed require higher 
> soldering temperatures.
> 
> Board materials and plating will have to change if you were using HAL,
> as Steve points out.  Many shops will not have gold available as a
> plating option however and will use matte tin instead.  This brings
> into play the "tin whisker" problem which it seems not everyone has
> solved yet.  Gold does not always solder as well as you might like
> since it can actually diffuse out into your solder.  Unless your shop
> uses some really bizarre fire-retardant, the plating should be the
> only board material problem.

Do the whiskers form even if you solder under molten colophonium?

CL<

Reply via email to