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Post by Jack ( Yorkshire) on May 11, 2011 3:12:52 GMT -5
Hi Steve & All. A lot of people want to know just a bit mor about tumbling and Formulars on how to work speeds of tumbling A example Page 31 working the speed out of a 24" barrel Take a easy one first a 24"barrel,The radius is 1 foot,The square root of one is one so 54.19 divided by one is 54.19 the" critical speed" in RPM. General practice is 50% of this or 27RPM as the operating speed For all intersted in Calculations ,Critical speeds, and constructions of a tumbler, Goop constiuancy Grit how it is made and graded , 5 pages on polishing different rocks a excelent little book first published in 1962 at $2 -00 A excelent book for the beginner and someone wanting Calculations and Formular to work out special problems on home made equipment Sold by the Rockshed ,This is a book called "Gem Tumbling and Baraque jewellery making " by the Victors , & here is a link to it now priced at $6 - 50 www.therockshed.com/grit.htmlIt has a lot of detail reserched from U.S. Stoneware and Norton abasives And even has a section on a" new" invention just coming onto the market - - -The Vibrating Tumbler ! ! ! ! Also a quaint saying about rock hounds, "Old Rockhounds never die, They just slowly Petrify " Jack Yorkshire uk Ps well I guess I will have to get on - - - "petrifying " ! ! !
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quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,352
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Post by quartz on May 11, 2011 22:27:27 GMT -5
Thanks for putting that up Jack, we started out using that book as a guide, lots of ideas, lots to learn. One thing we found, with our homemade tumblers, we started out using the speed values from the Victor's book, experimentation showed 20-25% slower worked better for us. Good book, worth today's price.
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Post by Jack ( Yorkshire) on May 13, 2011 16:16:00 GMT -5
Hi Quartz, Yes been a real help to me also so much information that IS usefull
Amazing it is still in publication must show how good it real is.
Jack Yorkshire uk
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