UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

Bazz4CQJ · 22nd Dec 2018, 7:55 pm

You've got an ultra-sonic bath; that's the most powerful means of cleaning you could want for something like this; don't get involved with any more brutal method until you've done all you can with the bath.

As for the medium; always start with something weak, at a modest temperature for a short time...and then progress there. I'd start with 50/50 IPA/water which will clean off anything organic and may loosen lots of dirt and oxide as a starting point, but will probably not go far enough. 5 minutes at 35'C to start. Check to see that there's no adverse effect and ratchet up from there. In water, there's always the potential for galvanic effects causing bad things to happen, so keep an eye on it. Dry with hair drier - don't leave wet. Chemicals; start with vinegar?

Stay the heck away from silicones; death!

Just used my ultrasonic bath to clean the local Vicar's small container for Holy wine; it is 116 years old and has religious / sentimental value; 100 year-old dried wine is stubborn, but I got it! Started off with vinegar (advocated on the internet for wine deposits), which was not helpful and progressed exactly as described to more potent media.

B

22nd Dec 2018, 7:55 pm	#6
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,934	Re: Variable capacitor oxidation You've got an ultra-sonic bath; that's the most powerful means of cleaning you could want for something like this; don't get involved with any more brutal method until you've done all you can with the bath. As for the medium; always start with something weak, at a modest temperature for a short time...and then progress there. I'd start with 50/50 IPA/water which will clean off anything organic and may loosen lots of dirt and oxide as a starting point, but will probably not go far enough. 5 minutes at 35'C to start. Check to see that there's no adverse effect and ratchet up from there. In water, there's always the potential for galvanic effects causing bad things to happen, so keep an eye on it. Dry with hair drier - don't leave wet. Chemicals; start with vinegar? Stay the heck away from silicones; death! Just used my ultrasonic bath to clean the local Vicar's small container for Holy wine; it is 116 years old and has religious / sentimental value; 100 year-old dried wine is stubborn, but I got it! Started off with vinegar (advocated on the internet for wine deposits), which was not helpful and progressed exactly as described to more potent media. B __________________ Saturn V had 6 million pounds of fuel. It would take thirty thousand strong men to lift it an inch. Last edited by Bazz4CQJ; 22nd Dec 2018 at 8:10 pm.