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Post by captbob on Oct 6, 2014 11:22:44 GMT -5
Thanks! Don't know how I missed that post. Just ordered 5lbs
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jamesp
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Post by jamesp on Oct 6, 2014 12:19:14 GMT -5
Thanks! Don't know how I missed that post. Just ordered 5lbs I should mention a situation where sugar solved a problem. Tumbling large corals with pointed edges were hell getting polish on sharp edges. They were sensitive about frosting. Kept thickening the slurry w/sugar, that's all. The thicker i got the slurry, the less frosting I got. Here are some examples. I never tried photos to show the shine until the obsidian came along. Was always showing the rock with minimal glare. These were run with real thick sugar in a rotary every step. They weigh 9-13 ounces and were all run together in a 16 pound barrel. It had smalls too but a bunch of 3-6 ounce chunks too. Showing the glare on the pressure points, (the white part does not polish):
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jamesp
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Post by jamesp on Oct 6, 2014 12:26:01 GMT -5
So the sugar was the only thing I kept adding and and it sure solved this one. Load was about half large and half smalls under 1.5 inches. It took about 3 attempts adding more sugar before it was thick enough. Got a pile of frosties in a bucket. They are road gravel.
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Post by pghram on Oct 6, 2014 15:17:09 GMT -5
Nice shine, I've never tried sugar. Those are some large specimens.
Rich
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jamesp
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Post by jamesp on Oct 7, 2014 10:00:37 GMT -5
Benefits of using sugar in a rotary tumbler 1) No need of filler, plastic pellets, ceramic 2) Tumbler full of rocks to be tumbled, no wasted space due to fillers 3) Lubrication 4) Makes slurry heavy keeping abrasives in suspension 5) Biologically degradable 6) Cheap 7) Prevents foam 8) Reduces bouncing and and promotes rubbing allowing abrasives to cut efficiently 9) Prevents concretion and settled areas allowing tumbler to run with more rocks to 7/8 fill 10) Equal distribution of protective coating
Perhaps it is not an accepted or popular method. The concept was passed to me from the late Bill Burke whom ran a lucrative rock business for over 60 years. He was a revolutionary type person that learned from many others during his long career in the business. One of his best attractants was a bowl of free tumbled chips to attract the kids(and then the parents) to his booth at rock shows. He was a sly businessman and a master lapidarian. One of his best bread winners was Australian opal that he purchased in some kind of a mud ball. He made many a trip there and hand picked the opals. Cut,set and sold them. He died early this year at the ripe old age of 91 of lung problems believed to be caused by rock dust. He was a very active man right up to his passing, and hard to keep up with on a rock expedition.
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jamesp
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Post by jamesp on Oct 8, 2014 11:11:41 GMT -5
Gas forming in the coarse grind has been an indicator of grind rate on obsidian. With two 16 pound barrels full of obsidian in coarse the rubber lids bulging tells me grind is good. It is part of the game in tumbling obsidian. One of these barrels is way ahead of the other and it is the one I have to burp daily. It is the one with double band clamps. Sometimes it is bulging a full inch. During finish grinds little gas is formed because less material is being removed and less gas pockets exposed. am stock piling coarse ground obsidians until finish methods are figured out. So these two barrels are constanty being added to as some obsidians finish early and are pulled and rough obsidian added. As long as the 30/60 SiC is not broken down obsidian will continue to be added. It just does not break down fast with the soft obsidian. Two 16 pound barrels of obsidian, caps flat, no pressure, bottom one with double clamps due to excessive gas: Agate barrel with vacuum, a good thing: 30 and 35 pound agate barrels, all good:
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Fossilman
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Post by Fossilman on Oct 8, 2014 12:51:32 GMT -5
Doing my homework and writing it down......Thumbs up
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jamesp
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Post by jamesp on Oct 8, 2014 13:12:42 GMT -5
Doing my homework and writing it down......Thumbs up Test tomorrow Michael
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Post by 1dave on Oct 8, 2014 13:41:24 GMT -5
"You master's of vibrators are brave"I don't know about other vibes but although a Lot-O-Tumbler looks like it has a violent action it's actually VERY gentle.If you stick a finger in when it's running it feels soft and gentle. Here you can see some very small pieces of obsidian (Tears)at the bottom of the photo that are not chipped or cracked.No sugar,no molasses,no Betty Crocker anything either! LOL This experiment your doing with the obsidian is VERY interesting and without those great photos it wouldn't be nearly as good for all of us to be able to relate to the whole thing. From this,,, To this,,,, Tells us all a lot abut what's really going on and your obsidian isn't even finished yet! You're going through a lot of work and taking a lot of time to stop the tumbler,wash the obsidian off,set it up for photos,choose which photos you will use,crop them,post them to a public web site,come here,write about you progress and then finally post the photos! MUCH appreciated James! connrock Question: Could those brown spots in the second photo be chunks of other material in the obsidian rather than holes?
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jamesp
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Post by jamesp on Oct 8, 2014 13:58:12 GMT -5
Could be Dave. All I can say is you sure sent me some nice glassy obsidian. The obsidian seems to pit instead of grind. Like grinding metal has scratches in it. This stuff looks sand blasted in every stage.
I see what you are talking about. Now that 30 grit pre-grinder sends little holes in it for some reason. But the 30/60 grit removes them after tumbling. Photo you are referring to is like early, say 2-3 days into the 30/60 tumble after pre-grind.
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Post by 1dave on Oct 8, 2014 16:47:03 GMT -5
Could be Dave. All I can say is you sure sent me some nice glassy obsidian. The obsidian seems to pit instead of grind. Like grinding metal has scratches in it. This stuff looks sand blasted in every stage. I see what you are talking about. Now that 30 grit pre-grinder sends little holes in it for some reason. But the 30/60 grit removes them after tumbling. Photo you are referring to is like early, say 2-3 days into the 30/60 tumble after pre-grind. To me those brown spots look almost like small chunks of fire agate. If it is something like that, they could be pulling out and leaving pits.
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jamesp
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Post by jamesp on Oct 8, 2014 17:06:51 GMT -5
Could be Dave. All I can say is you sure sent me some nice glassy obsidian. The obsidian seems to pit instead of grind. Like grinding metal has scratches in it. This stuff looks sand blasted in every stage. I see what you are talking about. Now that 30 grit pre-grinder sends little holes in it for some reason. But the 30/60 grit removes them after tumbling. Photo you are referring to is like early, say 2-3 days into the 30/60 tumble after pre-grind. To me those brown spots look almost like small chunks of fire agate. If it is something like that, they could be pulling out and leaving pits. You may know better than me Dave. New to the obsidian. Man I appreciate the sheen OB. I have had a great time tinkering w/it. Would that be normal to have fire agate in obsidian ? It must get impurities in it. I tried to grind the scale off of it where it was left natural.
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Post by 1dave on Oct 9, 2014 12:41:36 GMT -5
To me those brown spots look almost like small chunks of fire agate. If it is something like that, they could be pulling out and leaving pits. You may know better than me Dave. New to the obsidian. Man I appreciate the sheen OB. I have had a great time tinkering w/it. Would that be normal to have fire agate in obsidian ? It must get impurities in it. I tried to grind the scale off of it where it was left natural. You are the expert on tumbling. I went out and checked the surface of my gold sheen obsidian stash. The surfaces show some scratches, but no gas bubbles. The pits on your glass make me wonder if it isn't something in your tumbling process making the pits - impacts or the opposite, pulling fibers out ??
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Post by captbob on Oct 9, 2014 12:51:00 GMT -5
prolly sugar *snort* I crack myself up
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jamesp
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Post by jamesp on Oct 9, 2014 12:52:25 GMT -5
You may know better than me Dave. New to the obsidian. Man I appreciate the sheen OB. I have had a great time tinkering w/it. Would that be normal to have fire agate in obsidian ? It must get impurities in it. I tried to grind the scale off of it where it was left natural. You are the expert on tumbling. I went out and checked the surface of my gold sheen obsidian stash. The surfaces show some scratches, but no gas bubbles. The pits on your glass make me wonder if it isn't something in your tumbling process making the pits - impacts or the opposite, pulling fibers out ?? Could very well be Dave. I can not see them w/my eyes. They are sure tiny. I should look at an untumbled chip under magnification. But you may have already done that. Glass bad about tiny bubbles. Hard to remove in process.
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jamesp
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Post by jamesp on Oct 9, 2014 12:53:50 GMT -5
prolly sugar *snort* I crack myself up Yaint right captbob
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Post by 1dave on Oct 9, 2014 13:05:49 GMT -5
"I should look at an untumbled chip under magnification. But you may have already done that. Glass bad about tiny bubbles. Hard to remove in process." Read more: forum.rocktumblinghobby.com/thread/67462/macro-surface-photos-obsidian-barrels?page=13#ixzz3FfiDY2N4No, I didn't use a glass, and wouldn't have seen them if they are that small. If they are bubbles in the material, wearing off the exterior bubbles will just reveal the next layer of them. If that is what they are, the Beilby Layer could solve it. "The Beilby Layer What is the Beilby layer? It is a phenomenon that brings about a polished surface. Sir George Beilby (17 November 1850 – 1 August 1924) discovered that during polishing the surface of gemstones actually melted and flowed as a “glassy” layer over very fine scratches. He proved it by noting a certain scratch pattern, polishing the surface, and then recovering the scratch pattern by etching away the polished surface with acids." Read more: forum.rocktumblinghobby.com/thread/64304/collected-polishing-tips#ixzz3Ffjgp5a3
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jamesp
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Post by jamesp on Oct 9, 2014 14:12:07 GMT -5
I know glass makers remove grind marks with a torch to give a super 'hot shine'. That's another story. Would a tumbler do a Beilby shine ?
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Post by 1dave on Oct 10, 2014 10:37:10 GMT -5
I know glass makers remove grind marks with a torch to give a super 'hot shine'. That's another story. Would a tumbler do a Beilby shine ? I doubt it. Beilby used the term "melt," but it is really "crystallizing," molecules electromagnetically moving from a high spot to a low spot. Friction on a buff somehow produces it.
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jamesp
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Post by jamesp on Oct 10, 2014 13:29:03 GMT -5
I know glass makers remove grind marks with a torch to give a super 'hot shine'. That's another story. Would a tumbler do a Beilby shine ? I doubt it. Beilby used the term "melt," but it is really "crystallizing," molecules electromagnetically moving from a high spot to a low spot. Friction on a buff somehow produces it. The old buff can get something really hot. It seems to make base metals walk or smear.
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