Copper Plating???

[rake]

Guys;
Do y'all thing there would be any advantage to copper plating a chassis?
I've got a friend that has a setup to do copper plating. He uses it to plate the inside
of motorcycle fuel tanks he builds to prevent rusting. He offered me free use of it
so I might give it a try. Any and all thoughts appreciated.

[bmccowan]

Looking cool is the only advantage I can think of. Of course there is nothing wrong with that. A drawback would be keeping it looking good. Would you clear coat it with something? If not it will first get dull, like the copper pipes in your house, and then corrode in that turquoise color if exposed to moisture.

[Latole]

I will not do it .

[kagliostro]

On the past time some brand used a copper plate to have better connections.

There were both chassis plates and faceplate plates to perform better grounding but seems that with the time problems were more than benefits and this practice was discontinued

There is the doubt that that happened also because of copper price arise, but is not negabile that connection problems were present

Franco

[Merlin]

Would you clear coat it with something?

Clearcoated copper looks so cool

[shooter]

this blurry image was my GA-8T PSE, the top is copper buss bar they used in power sub-stations,  took a direct hit from lightning so it got "annealed"(sp?) hard as a rock to drill through


the next was copper foiled over the chassis
 

[uki]

this blurry image was my GA-8T PSE, the top is copper buss bar they used in power sub-stations,  took a direct hit from lightning so it got "annealed"(sp?) hard as a rock to drill through


the next was copper foiled over the chassis
 

I though it would only be done in the inside part of the chassis.

[acheld]

Agreed, there is no technical advantage to copper plating a chassis.

But those examples by Shooter are so cool, each in their own way, that it might be worth it if you can showcase the copper in some way.

[shooter]

my "goal" in amp building was to create "mantle pieces", "Conversation starters", that you could dust off, plug in and noodle around


copper is pretty useless as "RF" shielding at audio frequencies but walk into a properly shielded, copper "RF Cage" after it's finished, before the drywall goes up, now that'll put a smile on the face every time.

[rake]

I was wondering if there was any advantage as far as grounding being copper is a better conductor than steel.

As far as keeping it all bright and shiny, nitrocellulose lacquer does a pretty fair job.
I have my great uncle's 1950's "The Martin" tenor sax with a copper plated bell and keys
and it still shines like a newborn's bottom! Of course you have to make sure you don't fubar
the lacquer!

[acheld]

walk into a properly shielded, copper "RF Cage" after it's finished, before the drywall goes up, now that'll put a smile on the face every time.

Spoken like a guy who builds MRI's.   

As for copper being a better conductor than steel, of course it is.   But for tube amps like we are building, you'd have to work real hard to create a ground loop due to the material alone. There's just not that much difference in impedance over a short run.   I'm basing my opinion on theory -- I haven't actually built a copper chassis, despite thinking about it several times for aesthetics.

[Merlin]

I was wondering if there was any advantage as far as grounding being copper is a better conductor than steel.

The plating is so thin that I somewhat doubt it. Besides, the chassis should not be used as a conductor. I suppose it might provide a little better magnetic shielding at HF.

[HotBluePlates]

Do y'all thing there would be any advantage to copper plating a chassis?

On the past time some brand used a copper plate ...

Fender's first amps used a folded sheet of copper as the chassis.  No doubt it was easier to solder to form grounds.

You might consider, "If it was a great choice, why didn't Fender continue using a copper chassis?"

[shooter]

the frugality of Leo comes to mind 


 

[rake]

the frugality of Leo comes to mind 

That was my thought. Save a dime? No big deal. Save a bucket of dimes? 

Biggest reason I thought of it was, It's Free! lol!

[HotBluePlates]

the frugality of Leo comes to mind 

   - What about transformer weight?

   - What about copper oxide being a rectifier?  Not good for those soldered-grounds over time, if an imperfect joint ever allows air.

   - How about the need to bend the chassis to form a 5-sided box (in the 50s), and eventually cover that box with shielding screen (in the 60s)?

There were amps made even more-cheaply than Fender in the 1950s and 1960s.  I think we say "frugal Fender" maybe a bit too much.  It's cheaper to build a chassis using a simple metal brake & a sheet of copper, as long as you're only making 1 bend.  When a 5-sided box of steel is required (and your company reaches some production scale), it's cheaper to bend steel 4 times to make an open-ended box then use a large press and dies to stamp a couple sizes of end-caps to close those box.  But the press & dies are $$$$$$$$$$ when there is low production volume.


The original question was whether one should copper-plate their chassis.  Fender eventually did copper-plate their steel chassis, but only as a preliminary step for chrome-plating (in the 50s), or nickel-plating (in the 60s; later became zinc-plating and dropped the copper-step altogether).  Other posts already said there's not much advantage to copper-plating the homebrew, and I'd recommend aluminum over steel for most home-brew projects anyway.  Plus pre-punched steel chassis will likely already be treated with some sort of rust-prevention, unless the builder is daring enough to source their parts from Alibaba...

[shooter]

How about the need to bend the chassis to form a 5-sided box

 
I had a pretty good pile of plate aluminum, thicker than good chassis stock so I go asking around for who to see about getting it bend cuz a vise and sledge hammer were my skill sets,  a guy just a mile away had a box break, met up with him, walked into his 60 X 100 pole barn and was floored, inside was a perfectly preserved, fully functioning  "factory floor" machining shop, NC's, laths, breaks, drill presses,...
 guy was about 20 years my senior he told me;


"Came into a few dollars, decided to buy the factory I spent 40 years at"  It was a fully working, fully restored walk into circa 40's
he set up the break, made the bends, told me I was off on my lines with a chuckle, when I asked about paying;
 "You got $5?"  we shook hands n I walked away having met a truly amazing man.