[dconant]

Hello, I have a Philco 91 where the tuning condenser fins are rusty. I magnet sticks to them so they can't be aluminium. What would be the best way to get the rust off and preserve them from rusting again. It is just surface rust. The chassis has surface rust as well so I figured I would use naval jelly on that.

Thank you,
Dan

[RodB]

You could soak the fins in vinegar. You have to be careful if any pot metal is involved because the vinegar will dissolve the pot metal.

[RossH]

I would try Naval Jelly and use a soaked pipe cleaner to get it where it needs to go.

[dconant]

Thanks guys. I think I'll give the Naval Jelly a try since I can better control where it goes.

[morzh]

If you have rust between the vanes, I wonder how you get the NJ in between, and how you then wipe it off.

[David]

Give the tuner a good wash in Dawn and hot water. Then set tuner in a plastic container and cover with vinegar let soak until rust is gone may need to have a old tooth brush handy. Then mix baking soda and water together lots of baking soda. Place tuner in solution for 10 minutes and then rinse and dry. hair dryer works wonders. Spray with something of your choice to prevent rerusting. Like WD 40 or a clear coat.

[dconant]

David, RodB says to watch out for pot metal as it might dissolve in vinegar. I think there might be some in there. I think I'm going to pass on the vinegar and do the best I can with a fine wire brush on a Dremel. I didn't think it was a good idea to spray a tuning condenser with clear.

Mike I could use large pipe cleaners as Russ suggested and then wash off with Dawn and water.

[morzh]

I do not think Philco 91 used pot metal for the tuning cap. Also, in 1930-s pot metal did not have iron, being mostly copper/zinc/tin/lead/antimony

[GarySP]

I've put tuning caps with mica removed and vanes wide open in the dishwasher and ran through a cycle. When the dishwasher is finished it then goes straight into the oven at 200F for a hour or so to dry out. Just my $0.02 worth. Take care and BE HEALTHY! Gary

[RodB]

Gary, I once had a tuning cap that had a thick coat of kitchen grease and grime. So I had heard about brake cleaner being so efficient for removing grease and I just happened to have a spray can of it. It took the grease off but left a terrible petroleum odor. To get rid of the odor I put the cap in the dishwasher. Now the dishwasher stunk. Which meant another cycle to clean that out. What was the saying about draining the swamp?

[GarySP]

Hello Rob. I've also heard of soaking the tuning cap in automatic transmission fluid. This was an old trick we used to do to quiet noisy valve lifters. I don't know if I would put that in my wife's KitchenAid! Take care and BE HEALTHY! Gary

P.S. Don't get brake cleaner on painted surfaces! (don't ask me how I know ...)

[morzh]

Be careful with aluminum vane caps.
I did that, with dishwasher; it dulled the whole thing, which became grey.
No, no, it did work, just was grey.

Aluminum does not like dishwasher: I did the same to my aluminum pot once.

[Arran]

I would try something like Evaporust, or a similar product, there is a guy on Y.T that does this with aluminum fined tuning condensers and it doesn't seem to harm those. If you want to try vinegar mix it 50:50 with water, for some reason I find it works better at stripping rust then straight vinegar, if you want it to work faster heat up the mixture, since the Philco ones are all steel there should not be a problem. I did run a tuning condenser from a 40s radio through the dishwasher, it did not turn grey but it was spotty afterward, I would not have tried it except that the aluminum plates had scale on them, it did take the scale off.
Regards
Arran