How to ground pots?

[Oddvar R]

Another layout you can use.

Trainwreck Express Layout.pdf

Thanks for this, made certain points much clearer.

[M Fowler]

Your welcome.

[Aurora]

What happende to using these between the pots and chassis???

lug.jpg

[pompeiisneaks]

Those look like they'd be great. I've not seen them for sale on any of the amp building sites I frequent.

I also think, though, that even toothed washers can build up corrosion and lose contact since pots are one of the most frequently used parts of the amp. I've seen a few older amps where the washers and pots were very crusty around the connection to the chassis. This is why they're not always considered the 'best' point to guarantee ground contact.

~Phil

[Aurora]

Those are grounding lugs for RF connectors, and come in various sizes, - the BNC chassis versions fits perfectly, and are sold by all regular electronics suppliers like Mouser, Digikey and several others. I've literally used hundreds of those in my 40+ years in trade, and have yet to see them fail. I see your comment, but fail to see a logical reason why they should fail in a normal environment....

[pompeiisneaks]

Those are grounding lugs for RF connectors, and come in various sizes, - the BNC chassis versions fits perfectly, and are sold by all regular electronics suppliers like Mouser, Digikey and several others. I've literally used hundreds of those in my 40+ years in trade, and have yet to see them fail. I see your comment, but fail to see a logical reason why they should fail in a normal environment....

I think the 'normal environment' for guitar amps is a bit harder than other types... From my personal experience (both as a regularly gigging musician in my 20's to being an amp nerd now). A lot more beating and abusing etc. I've opened up only a handful of older amps and all had corrosion around the pots.

I've seen threads on some groups posting about the pots being bad as a source of ground for the same reason. Maybe those toothed washers avoid that better by doing that deep bite into the chassis and pot, and I have no experience there personally.

Could be that I'm full of crap

~Phil

[sluckey]

Doesn't really matter if they make a perfect ground connection that lasts forever. You still end up with multiple ground connections across the front panel. That goes against the wisdom of single preamp ground, single power amp ground.

[pompeiisneaks]

Doesn't really matter if they make a perfect ground connection that lasts forever. You still end up with multiple ground connections across the front panel. That goes against the wisdom of single preamp ground, single power amp ground.

Agreed, I guess I was understanding that those would be the 'only' ground for the pot, but I might be missing the point.

~Phil

[Aurora]

That may be a point, but the whole idea of single point ground, otherwise also advocated in pro audio, does not exist in the guitar amps I've seen....

[sluckey]

Not advocating single point ground either. I said single preamp ground and single power amp ground. That's two grounds total.

[gktamps]

A bit late to contribute a response, but here's how I ground all of my TW amps. Dead quiet other than gain hiss, which is of course not related.
I use grounding lugs similar to the one shown in a previous post, and a dab of silicone paste to help reduce effects of dissimilar-metal corrosion and oxidation of the aluminum contact area over time.