Fender Brass Plate

[Ed_Chambley]

I have read differing opinions on the brass plate behind the pots on fenders.  I am getting ready to begin assembling my newest build and have a brass plate.   I have always used them on fender builds, but I read in some places where it is best not to use it.  Keep in mind I built the chassis and had it chromed by the people how chrome the rollers on our printing presses.  The chrome is absolutely beautiful and the threw me a bone doing it.

Basically I am planning my grounding scheme.

Also, when adding a pot for a adjustable NFB, does the 3rd lug even need grounding and if so, can you just bend it and solder it to the body like in old Les Pauls?

[TubeGeek]

I don't use the brass plates anymore.  It's not really going to matter in the end, you can get away without it and it will not cause any issues.

Connect two of the nfb pot lugs together when wiring as a variable resistor like you want.

[HotBluePlates]

I'm not sure, but I think the biggest argument against the brass plate is that you might get galvanic corrosion due to dissimilar metals. So maybe in 40-50 years, there is a chance your grounding will be slightly degraded.

EXCEPT that Fender didn't use a chromed chassis in these amps. I'd think the chrome would help prevent any such corrosion and the resulting issues. Either way, you wouldn't likely notice a problem for 30-40 years or so.

[fdesalvo]

OT, but nice work and I love the lead braiding.  I learned to do 3 and 4 lead braids for my last build, but yours look really beautiful - tight and even. Something for me to work on for my next build.

[Tyrannocaster]

Ever seen a hot water heater that has brass plumbing fixtures meeting up with zinc ones? After a few years the electrolysis makes the whole thing rusty; I always assumed that's why you read the caveats about the brass plates in Fenders. Dissimilar metals do cause problems like that in the long term. Since the brass plate isn't necessary (the amps work fine without them), why bother?

[Ed_Chambley]

OT, but nice work and I love the lead braiding.  I learned to do 3 and 4 lead braids for my last build, but yours look really beautiful - tight and even. Something for me to work on for my next build.

Braiding 4 is easier than 3.  Twist 2, then the other 2 in the same direction.  Then twist the pairs and they will fall into the loops in the 2 pairs.  It looks like the 4 are braided, but it is really 2 sets of 2.

[mresistor]

I'm not sure, but I think the biggest argument against the brass plate is that you might get galvanic corrosion due to dissimilar metals. o.

I just pulled up the brass plate in a very early 66 Vibro Champ and it was pretty clean under there, and not causing any issues at all. But, if the amp were in a very humid location for a long time, I wonder if there wouldn't be some galvanic action going on between the metals.
this one has been OK for 46 years.

[HotBluePlates]

I'll save that picture!

Yeah, I've never had any problem with the brass plates. I was just saying that possible galvanic corrosion seems to be the root of suggestions against using the brass plate.

In any event, it was used as a production expedient. If you don't want to use one, just figure a different method to create a ground buss for your amp.