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Tumbling Machines

What is Tumbling ?

What is Tumbling ?

All stone polishing is based on abrading away the surface with a harder material and since the hardest material known is DIAMOND, it is frequently used. Because of the high price of DIAMOND we resort to the next best thing, a substance called SILICON-CARBIDE, which is a man-made hard grinding compound.
Before machines were invented, stones were polished by hand but it is very hard work on anything but the softer stones.




A better way of polishing stones is to use a Tumbling machine (also known as a tumble polisher, rock tumbler, pebble polisher or stone tumbler); these are small electrical units, using silicon carbide grit as mentioned above. Rough stones, of equal hardness, are put in a barrel with water and grit and the barrel is slowly rotated. The resulting rolling of the stones over each other, with abrasive grit between them, causes a smoothing and rounding action over a 2-4 week period. Barrelling, for a further week, with a polish powder and water, produces a gleaming long lasting shine on most stones.Owing to the relatively low levels of cost and skill required for tumble-polishing it still remains the most popular way of beginning to learn stone polishing and is suitable for anyone from the age of about eight upwards.Machinery purchased to do this does not become obsolete when a grinder/polisher is obtained at a later stage, as offcuts from individual stones can always be utilised in a tumbler, so there is no waste.
***Please note our machines are for 220/240volt use only****

Tumble-polishing Instructions

Tumble-polishing Instructions
Ref: IntroTumb
Our introduction to stone polishing often follows a period of pebble collecting.
We collect attractive stones, perhaps on holiday, and then take them home and wonder what to do with them. The beautiful colour and sparkle which the stones have when wet can be restored by polishing.
You can download rock polishing, rock tumbling or tumble polishing instructions (in Adobe pdf format) without charge..... click on the following line.....
Instruction leaflet download - may take a couple of minutes. Note: If the file appears incomplete you may need to download a free up-to-date version of Acrobat Reader - click on the logo in the left hand column.

Tumble-polishing Instructions for finishing Metal.
Ref: TumbleInstrMetal

We have produced brief outline instructions for finishing metal in a rotary tumble polisher.
Click here to download metal finishing tumbler instructions.

Our stock range of nearly 10,000 items covers hobby and professional requirements for craft/workshop/therapy use. E & O E. Copyright: Manchester Minerals Ltd. February 2015