Hi Jer, 
  
Solder spidering, or "Tin whiskers" has always been an issue, even when 60/40 
SnPb solder was the "standard". In the past decade, the switch to non lead, or 
RoHS compliant solders has, mandated the removal of Pb in solder. With the 
absence of Pb and a much higher content of Sn, typically 96.5% of the solder 
formulation, tin whiskering has become more of a taking point and in some 
cases, problems in micro and especially nano circuits. 
The typical formulation for solder paste (for reflow) and solder pots is 
96.5%Sn, 3%Ag, and .5%Cu. It's the brighteners in the Sn that are crucial to 
midagate the tin whisker growth. 
Although I did not see anything on the Elecraft web site that stated RoHS 
compliant, I would bet that their PCBs are being soldered with this type of 
RoHS compliant material, as Elecraft is selling into the EU marketplace, where 
these restrictions are enforced. 
  
As far as tin whiskering issues for the type of PCB's that are designed into 
these products, I do not think one should fear and "shorting" issues due to tin 
growth, as the pad spacing and line spacing is not at a critical spacing. Tin 
whisker growth is a very slow process, and we humans will probably be gone 
before anything like that would present a problem, especially in the "normal" 
conditions we operate the gear. 
  
I would be more concerned about cold solder connections as the newer RoHS 
solders require higher temps to reflow. That too has pretty much been handled 
over time with pretty precise solder reflow apparatus, and tweaks over the 
years on the paste and solder formulations. 
  
73 Gene, N9TF  

----- Original Message -----

From: "Jerry Moore" <je...@carolinaheli.com> 
To: elecraft@mailman.qth.net 
Sent: Wednesday, August 5, 2015 11:33:53 AM 
Subject: [Elecraft] K3S solder type? 

Anyone know the type of solder used in the K3S board manufacture? I've been 
reading up on environmentally safer solder and all of the reliability issues 
that result from the solder spidering over time. Anyone happen to know? 

I'm sure it's not an issue but it came to mind. I tried to call Elecraft to 
ask but they are busy helping customers who need actual help with their 
units J 

  

Jer 

______________________________________________________________ 
Elecraft mailing list 
Home: http://mailman.qth.net/mailman/listinfo/elecraft 
Help: http://mailman.qth.net/mmfaq.htm 
Post: mailto:Elecraft@mailman.qth.net 

This list hosted by: http://www.qsl.net 
Please help support this email list: http://www.qsl.net/donate.html 
Message delivered to n...@comcast.net 

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Reply via email to