Cleaning rust off Transformers?

[texwest]

I have a 68 Princeton in the shop I'm working on and it has A Lot of rust on the transformers.  Should I clean that off?

Like wire brush and Rust Oleum or will that make matters worse?

thanks

[66Strat]

If it were me, I would knock off loose rust with some sand paper and then paint with a rust converter. Most auto part stores carry clack clack cans of VHT Rust Converter.

[Latole]

Some well know amp tech who wrote many booka ( Gerald Weber ? ) wrote to not remove rust.
Wait for more answer before doing mistake

Mercury Magnetics :
" If you are still bothered by the cosmetic aspect of rust, never scrape off the rust to the point of exposing bare metal because you will bring back those nasty eddy currents. Instead, brush off the loose particles and re-paint the area with varnish. If you want to send your transformer to Mercury, we can re-dip it in varnish and bake it for a small fee. Transformer evaluations are always no charge providing you cover the shipping costs to and from Mercury. "

https://www.mercurymagnetics.com/transformer-rust-friend-or-foe/

In 2016 el34 Worl.com  answered

https://el34world.com/Forum/index.php?topic=14251.0

[PRR]

The tone is in the rust. Leave it. Or gently apply jet black oil-based wood stain.

[kagliostro]

Rust can be safely removed from end bells the way you prefer

other thing is to remove it from laminations

if it were me

I would rub the rusty part of the laminations with a coarse wool cloth and a little gun oil

and a lot of elbow grease

then I would degrease with a cotton cloth with a small quantity of thinner (dry type, acetone type)

and then use a spray color to refinish

Franco

[Latole]

Textwest,
We need to see pictures of the transformer, otherwise you might not get the best answer and this kind of repair is case by case.
With vintage, you must not make a mistake.

One thing is sure, right now I will never paint it. Amp may loose is value

[scstill]

The tone is in the rust. Leave it. Or gently apply jet black oil-based wood stain.

"Rust Never Sleeps"
and never mess with patina or tone....

[kagliostro]

The tone is in the rust.

it may be that we are not that far from the truth, in the sense that once the laminations were deliberately left to rust so that the oxide acted as an insulator between one and the other

today this function is performed by special insulating paints and this is certainly the case with the transformer in question

in any case it is preferable that the laminations are somehow "isolated" from each other

Franco

[texwest]

Thanks for all the replies! I got busy over the past 3 days and forgot to check this thread. 

I'm leaning toward doing nothing about it and leaving it just as it is.  I remember reading that mercury article many years ago, but wanted the opinion of the experts on here.

[dude]

Don’t screw with PT, you could destroy it, paint or corrosive liquid could get in the laminate and you could have a humming PT

[Latole]

Don’t screw with PT, you could destroy it, paint or corrosive liquid could get in the laminate and you could have a humming PT

100% right

And amp may loose is value as vintage

[mresistor]

take the end bells off to treat them..