Mike Young wrote:
> What's  the bigger picture around why you're doing this? Mechanical
> strength is next to nothing. The hole plating is not bonded to the
> board substrate, leaving only the pad's attachment to the board and the
> scrawny trace.

These pads will receive the leads for small helical antennas about 1 inch in
diameter.  These antennas are a separately built assembly.  They are a
carefully measured length of wire wrapped around a custom polyethalene
spindle which has its own mounting the PCB.  The antenna feed lines need to
be pretty exact, and are made from very stiff metal.  Trying to insert these
lines into holes while simultaneously aligning the spindle mounting parts
with the PCB is nearly impossible, especially when considering the
manufacturing tolerances on the exact position of the stiff antenna leads.

To solve this, we have the leads preformed so that their ends are at right
angles to the PCB.  They slide into the slots and are then soldered in place
by hand.  The spindle sort of snaps onto special holes in the PCB, and the
PCB and antennas are rigidly held separately by the case everything goes
into.  We don't need the leads mounted to the board to be strong at all.


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