Been thinking more on intermetalics of cold joints with less time in
preheat, Werner ;
as i managed to starve heat of mains connectors in past couple of times.
With cold barrel and cold pin inside, occasionally it did not gel.
My trouble was it did show months after in the field,
suffered a dented ego, luckily not many got through.
As Ed, i did chip wave, cosmetics looked great, only to bite my nails later.
Agree, it's a hard pick as what is a lesser evil ;
barrel as such, as you said, would not worry me.
The chill of the whole assembly would ,
+ the flux activity issues.
paul
-----Original Message-----
From: Werner Engelmaier [mailto:[log in to unmask]]
Sent: Saturday, 12 August 2000 5:26
To: [log in to unmask]
Subject: Re: [TN] Topside solder fillets after wave...
In a message dated 08/11/0 1:12:59, Ed Popielarski writes:
>Seems "bumping" the thermal mass with the chip wave followed by the
>"equillibrium time" in transit to the smooth wave was enough of a boost
>toovercome the ground plane sink effect.
In a message dated 08/11/0 1:12:59, [log in to unmask] writes:
>True, works up to an extend, nasty way to treat cold barrels (Werner must
>have an opinion on this),
Hi Paul and All,
Actually, this is less bad than the typical reflow, because the total
thermal
expansion of the resin is still likely less in this wave process than in
reflow--and T-shock has no special effect on PTHs. Also, since your fill the
via with solder, you would never know whether you cracked a barrel.
Werner Engelmaier
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