So I live near the ocean (Bay Area, CA) and have noticed how much quicker metal rusts in this saline environment. Transformer laminations and endbells are beginning to rust and pit. This is even true (though less so) for unused transformers stored in drawers.
So I’m looking for recommendations for ways of protecting these components from future corrosion. My best guess is to try applying a thin layer of a translucent dielectric grease with decent thermal conductivity (for power transformers). This is what I’ve found. I figure as dust deposits on the grease and begins to make it look dirty, I can simply wipe it off with a shop towel and reapply.
Open to other ideas as well. Potting my own transformers is not really something I’d be that enthusiastic about though.
So I’m looking for recommendations for ways of protecting these components from future corrosion. My best guess is to try applying a thin layer of a translucent dielectric grease with decent thermal conductivity (for power transformers). This is what I’ve found. I figure as dust deposits on the grease and begins to make it look dirty, I can simply wipe it off with a shop towel and reapply.
Open to other ideas as well. Potting my own transformers is not really something I’d be that enthusiastic about though.
Thanks for the tip. Sounds like rust converter/neutralizer would be good to stop and prevent rust. The directions recommend also painting over it, which is fine for the output transformer laminations but I’m not sure power transformer laminations would appreciate it.
The end bells on my ST-70 are bare metal, polished. Perhaps I can just sand off the rust, repolish, and wipe them with dielectric grease. I also see WD-40 makes a sprayable corrosion inhibitor. That may be the ticket as well.
The end bells on my ST-70 are bare metal, polished. Perhaps I can just sand off the rust, repolish, and wipe them with dielectric grease. I also see WD-40 makes a sprayable corrosion inhibitor. That may be the ticket as well.
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Just use barbecue paint or engine enamel if you want it colourful. My automotive experience with rust converter says you don't _NEED_ to paint it. No signs of rust after 2 years of salty winters. As well, IMHO paint isn't enough of a thermal insulator to raise the temperature much. I'm also 99% sure it's not an electrical conductor. The bell ends can be polished with any oil that won't smoke or catch fire (even turpentine will put a film on the metal). IMHO dielectric grease isn't necessary and will just make a mess.
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Thanks for sharing your experience. There’s a surprising lack of information on this topic. The rust converter and WD-40 inhibitor are the way I will proceed in the future.
WD-40 stinks, and will evaporate in months.
It is useful for emergency car ignition drying. It can be used on squeaks if you want the squeak to return in a year. It can be a first-touch on too-tight bolts (it is thinner than most oils). BTW, WD-40 is kerosene. Selected low-odor kero, not the run-of-the-still stuff for heaters, but just fancy kerosene.
While WD-40 will evaporate in months, it never really goes away, which means paint will never stick well.
In guitar amps, we say the rust adds mojo. It actually does NO harm (or good) to the audio. If it offends the eye, use a plastic scrubbie and then a good paint. If your climate gets through the paint, find a dryer place for the amp to live.
It is useful for emergency car ignition drying. It can be used on squeaks if you want the squeak to return in a year. It can be a first-touch on too-tight bolts (it is thinner than most oils). BTW, WD-40 is kerosene. Selected low-odor kero, not the run-of-the-still stuff for heaters, but just fancy kerosene.
While WD-40 will evaporate in months, it never really goes away, which means paint will never stick well.
In guitar amps, we say the rust adds mojo. It actually does NO harm (or good) to the audio. If it offends the eye, use a plastic scrubbie and then a good paint. If your climate gets through the paint, find a dryer place for the amp to live.
Personally, I like the smell of WD40... So what if it evaporates in months? Re-apply. Pennies a year. Rust converter will work better though. Funny, I was gonna say Kerosene or Diesel in my original reply.
Are you guys talking about run-of-the-mill WD-40 or this stuff:

The WD-40 was only being considered for the polished end bells, not the laminations.WD40 OR rust converter. Not both. 🙂
It’s not the moisture, it’s the saline air due to the proximity to the ocean. I didn’t have this problem in Portland, by all accounts a much wetter place to live.If your climate gets through the paint, find a dryer place for the amp to live.
I suggest to put the unused or stored parts, in a zipper bag and also a silica gel bag that previously has been well dried with hot air, for example.
You could always spray it with clear coat, too.
I had considered this but I was worried about it inhibiting the power transformer’s ability to dissipate heat. I’m probably being a bit too over cautious in this respect.
Great suggestion, thank youI suggest to put the unused or stored parts, in a zipper bag and also a silica gel bag that previously has been well dried with hot air, for example.
I wouldn't worry about a coat of paint and heat dissipation. Most transformers come painted from the factory, right?
And another idea would be a sacrificial anode like they use on the ships and bridges to inhibit corrosion, but that's probably overboard...
Galvanic anode - Wikipedia
Galvanic anode - Wikipedia
If the paint is porous and or the paint has bad adherence and or it is deteriorated, then no protection will be apparent.
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