Chemically polishing silver and plastic crystals

[spectre6000]

I have a small handful of NOS silver plated watches with plastic crystals. They're all black with tarnish, and I was hoping to chemically polish the cases (put them in a bowl with aluminum foil, baking soda, salt, and hot water), but want to make sure I don't need to remove the crystals first. I don't have any tools for rectangular crystals, and I'm not looking to invest in any if I don't have to. I've never done this, and while it doesn't seem like it should hurt the crystals at all, I'd rather be safe than sorry. Anyone ever done this or have any ideas what I should expect? Thanks.

[JohnR725]

Another option is something called an ionic cleaner. The first link has the machine and the special solution. You can also go to YouTube and there's lots of videos on using the machine. It just works super fantastic on tarnished items no heeds no ultrasonic and it takes less than a minute.

Then would always bothers me is because I'm cheap fortunately I didn't buy it it's at work. But attempting it doesn't seem very heavy and is powered off one of those little transformers so it makes you wonder what's really inside? The second link comments how to make one but they do skip something. There is a timer built into the machine so he put it in the machine you push the button and according to the YouTube video I was just looking at 45 seconds which seems about right. On rare occasions you might have to push the button twice.

https://www.amazon.com/Speed-Brite-Turbo-Ionic-Cleaner/dp/B003GF2VXA/ref=sr_1_3?dchild=1&keywords=ionic+cleaner&qid=1608580143&sr=8-3

 

https://www.ganoksin.com/article/make-ionic-cleaner/

[spectre6000]

Does that machine or the solution have any effect on plastic crystals?

[MechanicMike]

4 hours ago, spectre6000 said:

Does that machine or the solution have any effect on plastic crystals?

Got a piece of similar plastic, or a donor crystal to make a practice run?

[Nucejoe]

Hot water may warp watch crystals. Heat does.

 

 

[Endeavor]

13 hours ago, spectre6000 said:

put them in a bowl with aluminum foil, baking soda, salt, and hot water

I've done this "trick" many times. Started off with cooking water and let it cool down somewhat. I noticed that with the water cooled down to say 60-70 degrees C, the solution still works fine, perhaps the progress somewhat slower. Never experienced any deformation of an acrylic crystal. You could start off with a "low" temperature and see how it performs. Soda and aluminum foil comes cheap and you can easily make up another batch.

You could also go the other way, start cold and with the item submerged in the solution, start heating it, keeping an eye on the cleaning progress. You can always lift the item out the solution to check.

In general, the idea of aluminum foil with soda in a glass bowl works well .....

Edited December 22, 2020 by Endeavor

[JohnR725]

9 hours ago, spectre6000 said:

Does that machine or the solution have any effect on plastic crystals?

As far as I know it doesn't hurt plastic crystals. The unit itself is made out of plastic. It's also used at room temperature and it does not get hot. I kinda regarded as a magical device for removing tarnish.

[VWatchie]

Very interesting! So, this method works for silver. How about gold, stainless steel, and chrome/gold plated watch cases?

[JohnR725]

I have a link to the company that makes the machine.

Then there's a fact section which makes for an interesting read explains a lot. Even explains why it's good for cleaning stones which I found interesting because normally they don't conduct electricity. That's because basically this is a really mild cleaning solution used at room temperature. Then there's a reference to electropolishing Which Wikipedia makes me feel nervous? But I'm guessing this is the super mild version and I've never seen anything bad.

Then for other metals typically I've used it for things that are tarnished. Like watch plates the settings and watch plates. Occasionally I've used it to solve a nightmare? The ultrasonic machine that's used for cleaning bands cases whatever whatever they're using for the current fluid sometimes doesn't like nickel cases. Twice now I've put a nickel case in and it came out a gold color? Thinking about it now I really should have photographed it. But going in this machine I'm guessing the gold color was more of an oxide or something and then it went back to being a nickel case. The worst was a case with a chain which look like a bathtub chain. One of those things with little balls all attached each other you would never build a refinish that and it was gold. So it works miracles in situations that should never occur.

It wasn't just before the Christmas rush I would go find something tarnished and dip it halfway in and take a picture for you. But unfortunately were in the mall and the last days before Christmas are becoming a nightmare. Plus Seattle had a little snow we don't have snow and everyone panicked to get nice and quiet for the evening. I'll leave myself a note and see if I can find anything that looks tarnished and maybe clean it tomorrow.

 

https://speedbrite.com/

https://en.wikipedia.org/wiki/Electropolishing

[praezis]

Ionic Cleaner? A nice new word for something old and well known to goldsmiths (to watchmakers, too).

It is just the reverse of electrolytic plating (voltage 8-10V, item = +, metal wall 0r SS plate = -). Solute some powder for dish washing machines in water.

We use it for cleaning before plating, just in the ultrasonic cleaner.

Frank
 

Edited December 22, 2020 by praezis
Added info.

[spectre6000]

Alrighty... Well... Experiment under way. Never done this, seen it done, or heard about it being done prior to looking into it. What I found said aluminum foil, hot water, a tablespoon of salt, and tablespoon of baking soda with the tarnished silver in contact with the aluminum. Critically missing are quantities for everything but salt and baking soda...

I'm using a small Pyrex storage tray thing that doesn't get a ton of use in the kitchen. Probably has 2-3 cups of water in it. I tore out a sheet of foil about the length of the tray, then folded it in half (most efficient single tear size). I nuked the water for 2 minutes on high, stirred in the salt/baking soda until they dissolved, then dropped in the foil. Initially, I used a tablespoon of each without thinking, and I think that was a weak sauce, and it didn't do much. I ultimately doubled that, and that seems to be about saturated. 

The "recipe" said 5 minutes... That silver must not have been as tarnished as mine. These watches are NOS from (I think) the early 70s, so 50 years of tarnish took a lot longer than 5 minutes. Eventually, I put the tray in the oven on "dehydrate" which is supposed to be 150°. It also runs the fan, and with the extremely dry high altitude winter air, the water evaporated quite a bit, and I had crystals forming on the surface of the water. So, very saturated. 

I ran the watch under the sink, and noticed some of the black tarnish came off on my fingers. Not sure if that's good or bad, but it is. I topped the water back off, nuked it agin, and set the oven to a higher temp (180°, boiling is 198° here). It's working, but slowly. I imagine due mostly to the pretty extreme state of tarnish. 

Once I decide I'm done, I'll take some before/after photos. So far the plastic seems unharmed. 

Any thoughts on trying this with the stems? The crowns are the same tarnished silver, stems are stems, and there are some old gaskets, one of which has already crumbled a bit, so I wouldn't count on any manner of water resistance in the end result.