1) What Do I Need to Start Tumble Polishing Stones Myself? And What Will It Cost Me?
This two part series sets out what a beginning tumble polisher needs and how much it will cost. The costs and details reflect that I live in New Zealand, and the prices were accurate at the time of writing, April 2018. The account aims to be fairly thorough and realistic. Part One covers: The Tumbler; The Siting of the Tumbler; Silicon Carbide Grit; Grit Storage and Tablespoon Measuring; and Disposal of Slurry. Part Two covers: Tin Oxide Polish Powder; Polish Powder Storage and Mixing; Plastic Beads and Bead Storage; Soap for Cleaning and Burnishing; Sieves and Buckets; and Miscellaneous Useful Items.
NOTE: Due to changes in the supply of grit and polish (late 2020), these Posts have been revised (the changed text in the original Posts are in light green). Background details can be found in UP-DATE OF “What Do I Need to Start Tumble Polishing Stones Myself? And What Will It Cost Me?” Changing Prices, New Grits and Polish.
2) The Seven Stages in Tumble Polishing Stones
This at-present-incomplete Series goes through, step-by-step, the seven stages of polishing stones using a tumbler and 4lb barrel. A set of 40 beach stones collected from Riverton are used to illustrate each stage. Lots of photos show all the steps involved, often following individual stones (the stones are numbered 1 to 40). Stage One is Stone Collection (not usually included in accounts of tumble polishing). Stage Two is tumbling the stones for about a week in 100 mesh silicon carbide grit, then tumbling them in a soap wash for a few hours. Stage Three involves one week tumbling using 220 mesh silicon carbide grit, followed by a soap wash. Stage Four is the same procedure with 320 silicon carbide grit. Stage Five involves tumbling the stones in a tin oxide “Pre-Polish” powder (five microns in size) for three to five days, followed again by a few hours soap tumble. Stage Six is the “Pro-Polish” tumble, using tin oxide powder of one micron size, for at least one week. Stage Seven is a “burnishing” tumble for a week in borax. Inspecting and sorting of the stones also take place after each Stage.
NOTE: Due to changes in the supply of grit and polish (late 2020), six stages are now used – details can be found in UP-DATE OF “The Seven Stages in Tumble Polishing Stones” – One Less Stage.
Posts in the original Series to date are:
Stage One, Stone Collection, Riverton, 2-6 November 2017 – Topics include walking the beach, selecting stones, clothing, and equipment.
The Selected 40 Stones – Photos of the rough stones, dry and wet, and brief descriptions.
Stage Two, 100 Grit Tumble, 15-25 November 2017 – Step-by-step account of preparing the barrel and then emptying it after the tumble, disposal of slurry, cleaning of equipment, undertaking a soap wash afterwards, and finally determining weight loss of stones.
The Stones After 100 Grit and Their “Inspection” and “Sorting” Before Stage Three – Photos of the stones are presented after they have been through the 100 grit tumble, then an account is provided of the inspection of the stones, identifying the types of chips and holes and other “imperfections”.
Stage Three, 220 Grit Tumble, 4-13 December 2017 – This Post not only goes through the practicalities involved with the 220 grit tumble but also the inspection of the stones afterwards.
Stage Four, 320 Grit Tumble, 10-20 March 2018 – A repeat of the steps involved in Stages Two and Three but this time with 320 silicon carbide grit.
The Stones After 320 Grit and Their “Inspection” and “Sorting” Before Stage Five – Some minor issues with a number of stones are presented, illustrated with photos.
Stage Five, Pre-Polish Tumble, 28 August to 3 September 2018 – Includes an account of preparing the tumble and the soap wash afterwards.
The Stones After Pre-Polish and Their “Inspection” and “Sorting” Before Stage Six – This Post includes photos showing all 40 stones as they looked upon initial collection from the beach at Riverton and then upon completion of Stage Five, Pre-Polish, with the stones sitting on graph paper for size comparisons.
Stage Six, Pro-Polish Tumble, 1 October to 15 October 2018 – An account of tumbling in 1-micron Pro-Polish tin oxide powder.
Stage Seven, Borax Burnishing Tumble, 15 October to 25 October 2018 – Instead of undergoing a short soap wash after the Pro-Polish tumble, the stones are treated to at least one week’s tumbling in borax to help bring out the shine a little more. A summary of the tumbling stages and times is provided at the end of this Post.
The End Result, Stones One to Five – This Post examines how the first five of the 40 Riverton stones have emerged from the polishing process, comparing them with how they looked as rough stones fresh from the beach. Each stone is discussed and close-up photos are provided of their textures, colours and patterns.
3) The Best Rock Tumbling Book Around – “Modern Rock Tumbling” by Steve Hart (2008)
I read the book referred to in this Post after only a couple of weeks of my own tumbling venture and found it directly relevant and immediately useful. It remains the best I have come across. It is available both as a “real” (paper) book and an e-book.
4) Sources of Detailed Instructions for Tumble Polishing Stones
This Post is a list of seven sources I have found useful for the beginning (and also for the not-so-novice) rock tumbler. They share a number of things in common but often have their own unique ideas or pieces of advice.
5) How Stones Tumble in a Rotary Tumbler
A video is referred to in this Post showing the tumbling action when a barrel is too full or not full enough. A great help in understanding why a barrel should not have too many stones in it!
6) My New Sorting Container for Stones at Different Stages of Tumble Polishing
A good way to store stones which are destined for different stages of tumbling is presented in this Post, so you can group them until you have enough for a barrel load. This also enables you to inspect stones after a tumble and feel free to set aside those that need to repeat a stage.