problem with HF tumbler tarnishing silver and other metals
Have had the tumbler for months and have had problems with tarnishing metal.I have 2 lbs stainless shot and have run with the dawn (was told to use a drop)...ran for many hrs with and without metals in it. Silver turns gray, copper turns dark. Recently tried some polishing soap compound...same problem. Tried running for 8 hours with shot and soap to lean the barrel. Each time I change the solution I am using. Took my tumbler to lapidary class and we ran a shot cleaner for 2 hrs. Cleaned barrel and shot after and ran with water and soap..really didn't polish. Drained, rinsed and put in the polishing soap with some silver...still didn't polish. Am running the tumbler for a minimum of 3 hrs and cont to alternate polishing compound and region soap...cont to gray my silver. Will the water make a difference? Was using water from the tap which is softened. HELPPPP! I am beyond frustrated!!!
It's difficult to diagnose problems like you're having without actually seeing what's going on. One thing you mention, "...with the Dawn, was told to use a drop" could be part of your problem. I use a healthy squirt say a teaspoon or two. The soap helps to hold all the crud being removed from the surface of the metal in suspension and keeps it off the items being tumbled. I forgot to add the soap one time when tumbling and the items in the tumbler, including the shot, came out dirty feeling and not polished. I rinsed the whole business, added water AND dish soap, re-tumbled and all was well.
I've tried different types of water and didn't notice any difference. In my area of Florida, we have really yucky, high mineral content water. So, we have soft water and a reverse-osmosis spigot for drinking on the kitchen sink, but it all produces nicely tumbled-polished jewelry when put in the tumbler.
If your tumbler is from Harbor Freight (Chicago Tools) it is possible that the rubber used in the barrel may be the culprit even though the tumbler is months old. Also, one pound of shot is all that is needed in a 3-pound barrel. Too much weight in the barrel can slow the rotation speed which affects the tumble-polishing happening inside the barrel.
To help find a solution to your tumbling problem, try these things.
1. If you're using a 3lb. barrel, use only one pound of shot. Add just enough water to cover the items by 1/2 inch.
2. Use more dish soap. No, it does not have to be Dawn. Just make sure what ever you do use is a hand-wash dish soap and that it does not contain bleach or any kind of abrasive/scrubby stuff.
3. If you've got a HF tumbler and the above changes don't produce the results you're looking for, buy yourself a different tumbler. I have had no problems with the rubber barrels of the Thumblers Tumblers made by Tru-Square Metal Products or the Lortone tumblers.
I hope the above help you solve your tumbling woes!