I've had a few questions about using a tumbler to polish jewellery recently, so I thought that I'd write a blog post so I could refer people to it in the future rather than keeping typing up the same information in emails!
The photo above shows my rotary polishing tumbler - as you can see, it's seen better days but it gets a lot of use both in my workshop and at college when I take it in for my evening classes to use. It's about three years old now, but it still works perfectly. The tumbler consists of the motor unit with rollers on top that the barrel sits on, and a barrel with two with push on lids.
Inside the barrel there are three plastic blades. These help the jewellery and the shot (more about that in a bit) move around in the barrel rather than just keep on the outside as the barrel turns, a bit like the fins inside a washing machine. The shot I mentioned is the collection of metal bits and pieces you can see inside the barrel. I use stainless steel shot as there's no risk of it getting rusty. The shot acts like hundreds of tiny hammers gently hitting your jewellery hundreds of times, harden and polishing.
Here's how I use my tumbler:
- Fill the barrel about a third full with clean, stainless steel tumbling shot. Add enough water so that the shot is covered by a good 3cm or so of water, and then add a couple of drops of washing up liquid. The job of the soap is to lubricate the shot and to help hold the dirt that comes off the silver in suspension so that it doesn't go back on the jewellery! When I bought the tumbler I also bought some "tumbling compound" - a substance that is mainly soap and also smells of ammonia. At the time that I ran out, my supplier was out of stock. I had a look on the web for any ideas of what to use instead, and lots of people suggested washing up liquid. I've used it ever since - it does the job well and smells a lot nicer!!
- Add the jewellery, head pins, jump rings etc. I don't fill the barrel right up as you want everything to still have plenty of room to move otherwise it won't actually tumble!
- While I'm doing the above I also put hot water inside one of the lids (the other lid is obviously on the barrel) to soften it as this makes the next stage much easier. Push the lid on the barrel. You need to make sure that the lid is on tightly so that there aren't any leaks, and the best way to do this is to 'burb' out the excess air by pushing on the centre of the lid with the palm of your hand and lifting up a section of the rim - try this with a cold lid and you will soon see why I warm mine up!
- Dry the outside of the barrel so that it doesn't slip on the rollers.
- Place on the rollers and switch on! My tumbler doesn't have an on/off switch - I have to plug it in to turn it on, so I make certain that my hands are dry for this!
Because I use stainless steel shot I can store it in the water until I need to use the tumble again - which for me is the next day at the latest!
A couple of cautionary points:
- Do not tumble fine chains unless you enjoy spending hours de-tangling them!
- I open up my barrel inside a large plastic bowl, just in case. You definitely don't want to be chasing tiny bits of shot if they are dropped and go bouncing across the room. Trust me on this one - and if you don't want to take my word for it, go and read what happened to Anne at Contrariwise a couple of years ago! The shot is less likely to bounce out of a plastic bowl than a metal one.
- I don't tumble jewellery containing stones or beads, especially lampwork beads. I know pople who do. Most of them have not had any problems, a few have had stones crack, and I don't want to take that risk. Stone setting is always the last thing I do after polishing, oxidising etc.
Look, lots of pretty shiny bangles!
To answer a couple of questions in the comments (thank you Gemma and Vicky!), I bought my tumbler from www.silverclay.co.uk.
Make sure that you read the comments as there are some good tips in there!