I'm sure that filling vias with solder will enhance via reliability, but
wave soldering seems to be going by the wayside (albeit slowly).
for thru hole stuff people are going to intrusive (or invasive)
soldering which is squirting a bit paste in the hole and then putting
thru the oven with the rest of the reflow
bye bye wave
for the remaining cases where that doesn't work people are often using
selective fountain spray soldering
so this means that in the long those vias aren't going to get filled and
will have to posses adequate quality without being filled (IMHO)
Dennis Saputelli
Brad Velander wrote:
>
> Bruce,
> the issue of thermal stress cracking was not directly related to the
> thermal reliefs of vias. The thermal stress cracking was the reason for
> filling the vias with solder to supply a more reliable via under thermal
> extremes. The thermal relief just allowed easier soldering of the vias to
> meet the desired end result.
>
> Sincerely,
>
> Brad Velander
> Lead PCB Design
> Norsat International Inc.
> #100 - 4401 Still Creek Dr.,
> Burnaby, B.C., Canada.
> V5C6G9.
> voice: (604) 292-9089 (direct line)
> fax: (604) 292-9010
> email: [EMAIL PROTECTED]
> www: www.norsat.com
>
> -----Original Message-----
> From: TSListServer [mailto:[EMAIL PROTECTED]]On
> Behalf Of Bruce Walter
> Sent: Wednesday, February 21, 2001 1:34 PM
> To: Multiple recipients of list proteledausers
> Subject: [PROTEL EDA USERS]: Plane Stitching
>
> <SNIP>
>
> Now, I don't solder to these stitches, so I have them as direct connect.
> Did I see something suggesting this could have thermal stress cracking
> problems on FR4? If so, how does the thermal relief lessen this effect? (no
> solder)
>
--
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