> Using less soldering will help, as said, and also
> keeping the capacitor well down on the PCB (not lifted by the solder on i=
ts
> pads).=20

Umm, that contradicts practice in the space industry. ESA guidelines specif=
y 0 to 0.4mm elevation of the capacitor off the PCB so that the solder can =
flex and provide some mechanical relief. Also the PCB is kept over a heater=
 that maintains it at around 75C, and the component heated to anywhere betw=
een 100C and 150C before getting a soldering iron near them. This all minim=
ises the thermal shock during soldering, and in reflow soldering this is al=
l done by the temperature profile.

> Lead-free soldering causes less stress than Sn-Pb soldering, because it's
> significantly stiffer than the "older" soldering [ see
> http://www.dfrsolutions.com/pdfs/2006_Cracking_Pb-free.pdf ]. My
> application is Sn-Pb (automotive, RoHS exempt) and thus is "weaker" (for
> once!).

Haven't looked at that document yet, but cannot understand why a solder tha=
t gives less flexure is better when the component and PCB have significantl=
y different temp coefficients.

Thanks for all the links anyway, I will be having a look at them to see wha=
t I can specifically learn.


--=20
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--=20
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