Date:         Wed, 6 Feb 2013 11:17:02 -0800
Reply-To:     Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject:      Re: No Start Cause: Relay Failure. PICS, Thoughts.
Comments: To: David Beierl <dbeierl@ATTGLOBAL.NET>
In-Reply-To:  <vanagon%2013020604350958@GERRY.VANAGON.COM>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

re : the solder used in the wave tank will have had a mushy
zone between solidus and liquidus.

What is a wave tank please ?


On 2/6/2013 1:34 AM, David Beierl wrote:
> At 01:42 AM 2/6/2013, neil n wrote:
>> https://lh4.googleusercontent.com/-h3JODsFUDHM/URHsPfqBbZI/AAAAAAAAGy4/5DkyKweHpnc/s576/Jetta%2520Power%2520Supply%2520Relay%2520Solder%2520Crack.jpg
>>
>>
>> https://lh3.googleusercontent.com/-vmq-vUhQT4s/URHsPue73gI/AAAAAAAAGzA/cNsoAUx6cJw/s640/Jetta%2520Power%2520Supply%2520Relay%2520Solder%2520Crack%25202.jpg
>>
>
> Fascinating.  As Dick says, the flux suggests prior rework.  The
> first image clearly shows a large melt zone caused by arcing around
> the terminal (delimited by the curved line midway between the
> terminal and lead), and in the second there appears to be a fracture
> zone around the righthand lead as well, not surprising under the
> circumstances.  Since 63/37 solder (which solidifies abruptly) is
> expensive, the solder used in the wave tank will have had a mushy
> zone between solidus and liquidus.
>
> This relay clearly was not designed to be used without a socket to
> mechanically support the terminals, and/or the mechanical staking of
> the terminal into the relay baseplate has failed.  I'd suggest
> getting a socket under it or its replacement if at all possible.
>
> Yours,
> d
>