On Mar 4, 2010, at 8:40 AM, Marechiare wrote:

>> Cinching is like NASA practice or something. ;-)
>
> Can't they just afford double sided boards? :-)

So you're saying that cinching is only "required" on single sided  
boards?  Hmm.  I've never had "training" on SS assembly, and I don't  
think I've ever been involved with professional assembly of anything  
with less than two sides.

However, I have in front of me two SS PCBs from consumer equipment.   
One is the controller from a PC keyboard, and one is the AC-side of a  
non-switching power supply for some AV equipment of some kind.  The  
breakdown is interesting:

Cinched: jumpers, LEDs, small ceramic caps, resistors.
Not cinched: connectors (include the AC power connector), 40-pin DIP  
IC,  Electrolytic cap, large 60Hz power transformer, fuse holder.   
(The power transformer is sorta interesting, because it has huge  
"pads", a star-shaped solder mask, and quite substantial amounts of  
solder.

Theory: the machine that does automatic insertion of axial components  
automatically cinches the leads, so those get done.  Heavy leads that  
aren't cinchable don't get done.  Other components are random.

OTOH, modern consumer electronics is not exactly known for extreme  
reliability.  On the third hand I don't often see solder joints blamed  
for failures.  (and on the forth hand, it isn't often that anyone does  
failure analysis.  I did have a TV that was "fixed" by re-heating some  
of the joints in the power supply...)

BillW

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