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Subject: Re: [Homebrew_PCBs] SMT resistor vias

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-11-18

On Fri, 18 Nov 2005 11:05:53 +0100, Mike Young <mikewhy@...>
wrote:

>
> Now he tells me. What a pain the arse ∗that∗ is. I just reworked a DS
>
> board to single side, and got it down to "only" 10 jumpers.
>
>
> Speaking of vias, a few of them ended up under the chips. The SO packages
>
> barely make it, with a standoff height of 4 mils. I have one more SSOP
>
> package to glue on, due here tomorrow. I'm expecting trouble with that
> one.
>
> The spec says only 2 mils available underneath. Any advice? It's not
> just a
>
> via any more; it's a jumper now in a 24 mil hole on a SS board.
>
>
> I think it's time for the heat gun; start over.


my advice is:

avoid it! ;-)


if there's space, lift the trace, drill a larger hole where it was, bend
it down into it and solder in there.


I've had to connect to the exposed pad to heatsink a flat component
recently, and i drilled a larger hole and filled with solder. Surface
tension is not your friend here, i think some stranded wire pieces stuck
into the hole might have made it easier.

ST