Blade/lever switch ground?

[Chad]

I’ve noticed that on guitars with a toggle-style pickup selector switch, the switch itself often gets grounded. But I’m wiring a guitar with a 3-way blade switch and I’ve noticed most diagrams don’t show that style of switch getting grounded? Why is that?

By the way, this guitar doesn’t have a pickguard or control plate. It’s rear-routed. But the switch does seem to be getting grounded through the shielding paint. It’s just odd that they usually wire ground one style of switch and not the other? Thanks.

 

[Teleplayer]

As you noted, when there is metal foil on the underside of the pickguard, the frame of the blade switch will be grounded to the case of the volume pot.

IMO, the grounding of the switch frame via conductive paint is sufficient because the ground is only needed for protection againt ESD interference noise (static electricity). Either conductive paint or a small amount of metal foil would serve this purpose.

 

[Artie]

I’ve noticed that on guitars with a toggle-style pickup selector switch, the switch itself often gets grounded. But I’m wiring a guitar with a 3-way blade switch and I’ve noticed most diagrams don’t show that style of switch getting grounded? Why is that?

Great question. Guitar wiring has always been a bit "wacky" as compared to conventional electronic principles. Many years ago, I emailed both Bourns and CTS with the same question: "What's the proper technique to solder to the back of a potentiometer?" They both responded with essentially the same answer. "Don't do it. A pot cover isn't designed to be soldered to."

Yet virtually all guitar wiring is done this way. There's no good answer.

 

[Mincer]

Great question. Guitar wiring has always been a bit "wacky" as compared to conventional electronic principles. Many years ago, I emailed both Bourns and CTS with the same question: "What's the proper technique to solder to the back of a potentiometer?" They both responded with essentially the same answer. "Don't do it. A pot cover isn't designed to be soldered to."

Yet virtually all guitar wiring is done this way. There's no good answer.

Interesting that they gave that answer. I wonder how they recommended grounding, then?

 

[hamerfan]

I think they would connect the ground lugs with a covered wire to the jack like in an amp. But a star ground is only necessary for higher voltages.
I recently made a harness with rectangular so called Premium Bourns pots, which don‘t have a real cap on the pots.

 

[Artie]

Interesting that they gave that answer. I wonder how they recommended grounding, then?

These things:

 

[Artie]

Mind you, I'll continue to solder to a pot cover, (carefully), but that's whet they recommended.

 

[Mincer]

These things:

I can't recall a guitar that has those inside. Why don't they just make pots more solder-able?

 

[Artie]

I can't recall a guitar that has those inside. Why don't they just make pots more solder-able?

I don't either. But you do have to use those with the Bourns Model 82 and 95 Cermet pots. They have plastic housings. I haven't tried the 82, but I like the 95's.

 

[MikeS]

These things:

Interesting... might have saved me a burned up pot or two in the past.

I assume guitars use the backs of the pots because it's convenient and saves a little bit of wire. It also seems as though the pot casing would be one of the easiest places to ground a braided shield.