Tumble Polishing Causing My Jewelry to Tarnish?

by Sharon Emery
(Wayne, Maine)

Tarnish Coating on Sterling Silver

Tarnish Coating on Sterling Silver


I've been trying to tumble polish for a week now and am having troubles with a coating that looks like tarnish.

My sterling and copper pieces go into the tumbler clean and without tarnish. But they come out with an ugly deposit of tarnish on them!

I'm using a Harbor Freight tumbler, with stainless steel mixed shape shot and blue Dawn dish liquid. I've tried changing the water and soap several times with no improvement. The first soapy water usually comes out dirty, but subsequent changes are clear. And yet the tarnish never goes away... I've tried polishing longer (4 hours) with no effect. I've tried 4 other other dish liquids other than Dawn with the same results...

I'm new to this, and Googled every where and can't find an answer to my issue. I'm pulling my hair out! Any thoughts?

I attached a photo of a sterling silver piece for you to see. The coating does come off with tarnish remover, but I'd like to solve the issue.




Stacy's Answer:

Hi Sharon! It sounds like you are doing all the right things with your tumbler. However, I'm unclear as to what you are showing me in this picture as it is obviously not a finished piece of jewelry. Did you anneal this item first? If so, you need to clean it in your pickle solution before tumbling. Tumbling will not remove torch residue, firescale or heat patinas.

Sometimes the rubber leaches in the inexpensive rubber barrels such as the ones from Harbor Freight. It will discolor the water and sometimes items in the barrel as well. Usually this "leaching" goes away after about a week of tumbling when the barrel becomes "seasoned." I've never had items that went in clean come out dirty, unless there was a build-up of residue on my stainless steel shot or on the rubber barrel itself.

You say that your water comes out clear after the initial tumbling.......perhaps all you're doing now is polishing the discolored metal. Are you sure that the metal you are tumbling is Sterling silver or pure copper and not plated??? Plate will be removed by tumbling, revealing the base metal underneath. This looks kinda grey and yucky! Doesn't sound like this is the case as you said that the tarnish remover cleans it up.

The tumbling action could just be polishing your "stained" or dirty metal and not removing the tarnish. Try using a burnishing compound like Rio Grande's Burnishing Solution for tumbling Sterling silver and copper. However if it's plated base metal, no amount of tumbling will make a difference. I do not recommend using the Burnishing Compound for tumbling oxidized items that you wish to remain oxidized! The solution has a tendency to make your patina'd items come out spotty.

First, check to make sure that you are not tumbling plated base metal items....the tumbler will remove the plating! If that does not work, then I would recommend investing in a better quality tumbler such as those made by Lortone.

Comments for Tumble Polishing Causing My Jewelry to Tarnish?

Click here to add your own comments

Nov 19, 2010
Tarnished Tumble
by: Deb Mae

Harbor Frieght tumblers are not very good they will blacken your pieces till they are very seasoned thus also coating your ss shot. I threw out my HF tumbler. But many say after enough tumbling stating 10 times or more it will heal the rubber and your good. You should clean your SS shot with Flat Coca Cola, make sure that you let it sit out and go flat, then use this to tumble your shot in and it will clean your shot and help the blackening of your metals. *** Only if your metal is not plated though.

Nov 23, 2010
I fixed it!
by: Sharon Emery

Stacy, The silver was clean when it went into the tumbler. It had been pickled clean and thoroughly sanded with sanding wheels on a dremel. It just needed to be burnished in the tumbler. That picture is what it looked like after it came out of the tumbler! Ick! The deposit was coming from the tumbler! And I've never used plate. That was solid sterling.

Somewhere, somehow, I seemed to have picked up a contamination on my steel shot. I searched the net and finally found several suggestions.

First, I tumbled the steel shot in flat coke for 3 hours. That seemed to help a little. Then I tried tumbling it in a thin baking soda paste. That helped a little more. Finally I tumbled the shot in Red Devil Lye (2 tablespoons to 2 ounces of water) and followed that by tumbling it in janitorial strength ammonia. It's finally clean!!! But whatever it was, it was nasty as it took the lye and ammonia to clean it up! I read that you can also use Draino (as Red Devil is sometimes hard to find) and to use janitorial strength ammonia that you buy in a hardware store. It's stronger than what you find at the grocery store.

And Deb, you're right about Harbor Freight Tumblers. Harbor Freight is cheap, and you get what you pay for. I've had bad luck with other tools from them in the past. But I gave them a shot with this, as others had reported good luck with them. The belts on these tumblers are cheap, I've gone through 3 of them in about 3 months! So if anyone else is thinking about buying a HF tumbler, buy extra belts!

Thanks for the suggestions!


Jan 12, 2011
this same thing happened to me
by: Anonymous

I had to torch the piece to get rid of the golden color all over the piece!
next time I used only water ,no soap ,and perfect results in my harbor freigth tumbler.
since then I dont use any soap in my tumbler ,you dont need it!.

Sep 17, 2013
Citrus bad.
by: T.

I had an issue when I first started tumbling, and it took some time to figure out that the culprit was the grapefruit dish soap (which is citrus and reacts badly with silver. Once I switched to Palmolive, all is good.

Click here to add your own comments

Return to Tumble Polishing Q & A.