Well, FR-4 says peel strength 11 lbs/in. So, however much stress you expect on a connector of so-and-so width..?
We're talking peel strength, so if you can guarantee the pulling force will never be more than so-and-so (and evenly distributed, not twisting/flexing), you'll be pretty good. And probably as good as anything through hole (you contend with solder mushing out of pins, and laminate strength around smaller pins, versus laminate strength around big pads).
Connectors on the edge of the board, with a lot of leverage, will peel off in no time. Weren't the BNCs in the early TDS1000s notoriously shitty SMTs?
I would consider SMT connects sufficient for internal connectors (which have to withstand shock&vibe, assembly and infrequent service, but not users), and not for external.
Tim
--
Seven Transistor Labs
Electrical Engineering Consultation
Website: http://seventransistorlabs.com
"Don Y" wrote in message
news:m075tn$kc0$1@speranza.aioe.org...
> Hi,
>
> "Guidance" (rules-of-thumb) for relative mechanical strength
> of connectors fastened to PCB *solely* by their electrical
> contacts (no metal shells, swaged protrusions, etc.) in terms
> of stresses from the user trying to mate/unmate the connector
> in SMT vs thru-hole forms?
>
> Are connectors in which insertion is normal to the PCB worse
> (in either technology) than those where the forces are *along*
> the plane of the PCB?
>
> Any rule of thumb re: (total) foil areas vs. forces (without
> risking lifting foils or compromising mechanical strength?
>
> Thx,
> --don