non-conductive hardware mounting

[jessenator]

So this came out of observing a recent troubleshooting thread, but it's made me wonder: why do components like 9mm pots have "pads" where the metal spring-lite clasps mount to to the PCB?

Why is it metalized? Can it just be a drill in the gerbers with no pad? I suppose structural strength, but then again, fiberglass or whatever resin compound it's made from isn't exactly flimsy.

Just something I've wondered about.

In other applications it could be a grounding point, but if there's no conductivity, ground included, then why?

[jimilee]

So this came out of observing a recent troubleshooting thread, but it's made me wonder: why do components like 9mm pots have "pads" where the metal spring-lite clasps mount to to the PCB?

Why is it metalized? Can it just be a drill in the gerbers with no pad? I suppose structural strength, but then again, fiberglass or whatever resin compound it's made from isn't exactly flimsy.

Just something I've wondered about.

In other applications it could be a grounding point, but if there's no conductivity, ground included, then why?

Just from my observations, the pins are wet small and most likely not strong enough to hold the board without a little help. That's just my thought, anyway.


Sent from my iPhone using Tapatalk

[jessenator]

Just from my observations, the pins are wet small and most likely not strong enough to hold the board without a little help. That's just my thought, anyway.

Totally. Totally agree agree they're necessary for stability.

Curious why the drill points need to have pad-like contacts on them and they can't just be drilled out and that's that.

[jwin615]

They only pinch so much.
Better to physically adhere them. And since you already have the iron in your hand... Why not use that?
Say you are floating a control board with 5 9mm pots in a straight line. GBMTO or OTBMBG...
And below it, you have a multifx dsp.
Everything on the lower pcb needs the higher pcb to not ---- up and touch it.
I say this not in theory as this was basically every Peavey digital pedal I've ever seen, not that there were many.
Obviously the pots were not designed for pedals, but the PCBs were.
Anytime you design, what's the worst case.scenerio?
In pedalsz it's "overly excited 300+ pound bass player"
So, what's the best part selection for that, short of those whacky tone-lok gizmos Ibanez used for 6 weeks? A pot with 5 solid points of contact.
Also. I may know the troubleshooting post your referring to, and I highly suspect any porition of the issue was lack of solder on the mounting tabs.  Reflowing the other connections likely solved that one.
I'm exhausted. Hope the above is legible. G'ni...

[jessenator]

Oh okay. I didn't even think about doubling up and soldering the clipped in portions. Granted I've never done a build that was mostly 9mm. Except for my bloody awful megecho clone layout. I think that was 3:2 or something. Had its own problems besides the pot stems.

Board mounted potentiometers was a mistake  /s

I guess that will make me a bit more judicious about their application.