jamesp
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Post by jamesp on Oct 3, 2017 6:43:02 GMT -5
Damn soft rocks. Please hear me out. They round and shape quickly with SiC 30-46-60. Great ! No one likes the 2 month coarse grind for agate(for well shaped/rounded stones). What if you could coarse grind obsidian/fluorite/rhyolite/apatite/felspar and other soft rocks in a week or two using SiC 30-46-60 and then get a wet polish ? Coarse grind is easy, polishing soft rocks is difficult in a tumbler. Since a tumbler depends on breaking down abrasives to get a polish soft rocks are slow going. IMO, soft rocks do not break AO down quickly because it is Mohs 9. Mohs 7 rocks will sure nuff break it down. 7 verses 9, a fair fight. So you have to run more steps 120-220-500-1000-14,000 etc. And use 50 to 75% ceramic media to help break down the abrasive(talking vibe here). So. IMO again, use a softer abrasive on softer rocks so it will break down. Without a ton of ceramic media. Been looking for softer abrasive. Finally found one, pumice(in abrasive form). Looks like pumice 100 grit. Maybe 180. Pumice is bit variable, known to have Mohs 7 silicates. However it can be quite pure(free of quartz type silicates) if mined in the right place. Pure pumice is softer at Mohs 6. So, after some research (thinking obsidian here, obsidian = glass). Glass varies Mohs 4.5 to 5.5 in most cases. 1davePlease read from this article aboutpumice.com/pumice-uses.html : "PUMICE USES Industrial Abrasive Pumice Pumice is widely used as an industrial abrasive where the protection of the surface is critical. Various grades and blended grades of pumice are used to: Polish glass, clean and texturize electronic circuit boards, clean lithographic plates, prepare metal surfaces for electroplating, buff leather and fine furniture woods, act as a tumbling media for things like buttons, cutlery, small metal or plastic parts." This is the pumice found off of Ebay, again 100-180 grit guessing(referred to as size 0-1/2 whatever that is): Could be made by captbob down in Florida... So my plan is to take my pile of well shaped poorly polished soft stones and give them a go in the vibe with the pumice. Will use Borax for thickener/lubricant. And if that does not work a thicker slurry of sugar. Please, wish me well.
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jamesp
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Post by jamesp on Oct 3, 2017 6:57:25 GMT -5
Hey folks, pumice is your friend Cheap too. And comes in various grit sizes. hmmm
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jamesp
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Post by jamesp on Oct 3, 2017 7:00:11 GMT -5
I purchased 0-1/2 grade on Ebay. Other sizes abound. 2F and 4F. Medium fine and very fine.
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jamesp
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Post by jamesp on Oct 3, 2017 7:11:43 GMT -5
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Post by fantastic5 on Oct 3, 2017 7:35:30 GMT -5
Looking forward to your experiment!
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Wooferhound
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Lortone QT66 and 3A
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Post by Wooferhound on Oct 3, 2017 7:51:12 GMT -5
Instead of borax ... use "Lava" soap ...
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Post by 1dave on Oct 3, 2017 8:45:20 GMT -5
The item that surprised me is:
It looks like a good find!
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jamesp
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Post by jamesp on Oct 3, 2017 9:50:39 GMT -5
The item that surprised me is: It looks like a good find! Graphite is a buggar to remove. A lot of steel stampings have graphite pressed on to it as it makes a fine high pressure lubricant. The wire wheels on a hand grinder just smears it. Flash rust removes it instantly. Started up the vibe this morning with the pumice and Borax. Tossed a few 500 finish obsidians in with polished agates. A fluorite or two. Hoping to go from a 500 to a 14,000 finish in a day. Lots of doubts but worth try. Pumice noted for being porous and breaking down fast. Will see.
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jamesp
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Post by jamesp on Oct 3, 2017 9:53:53 GMT -5
Looking forward to your experiment! Dang soft stones and their hatred for a tumble polish. Feeling a tug from the south today. Will report back soon if the river does not call me away. At 260 and falling 30/day.
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jamesp
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Post by jamesp on Oct 3, 2017 10:33:18 GMT -5
Instead of borax ... use "Lava" soap ... That just may be a great idea woofer.
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Post by fantastic5 on Oct 3, 2017 10:48:48 GMT -5
Looking forward to your experiment! Dang soft stones and their hatred for a tumble polish. Feeling a tug from the south today. Will report back soon if the river does not call me away. At 260 and falling 30/day. Been so busy with the house, I haven't assembled my mud motor yet. Could possibly talk DH into the trip this weekend, but I'm not sure how I feel about a virgin motor/helmsmen on that river. Was really hoping for something more forgiving for the first outing.
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jamesp
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Post by jamesp on Oct 3, 2017 10:56:56 GMT -5
Dang soft stones and their hatred for a tumble polish. Feeling a tug from the south today. Will report back soon if the river does not call me away. At 260 and falling 30/day. Been so busy with the house, I haven't assembled my mud motor yet. Could possibly talk DH into the trip this weekend, but I'm not sure how I feel about a virgin motor/helmsmen on that river. Was really hoping for something more forgiving for the first outing. I will say that a lake trip to try it out may be the best way to go. Going upstream on a river works fine. Except at the bridge we visited, up stream has that fast water there just above the bridge. I have gone up stream there in the winter and had to get in the water. froze. Hurried upstream and built a fire to warm up. Looking like rain starting Saturday and lasting a while. Good chance anyway. Been a bad year for warm weather coral hunting. Sorry.
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jamesp
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Post by jamesp on Oct 3, 2017 14:15:57 GMT -5
fantastic5Packed and leaving shortly, do-Wed-Thurs-Fri maybe Sat. Quality Inn Lake Park, same place as before. They did a reno on the hotel, it needed it. River should be at 260 tomorrow. 45 miles away the Suwannee is ripping at 5500, go figure. They are about equal in flow, both best to collect about 100 to 200. River higher than i want, may go way down and find a big shoal I scored well at on an over night kayak trip long ago. The Suwannee drains the Okeefenokee, a big catchment, slower to drain because of it's heavy foliage. It was hit by Irma and got filled up good. It also stays warmer longer.
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Post by fantastic5 on Oct 4, 2017 6:34:37 GMT -5
fantastic5Packed and leaving shortly, do-Wed-Thurs-Fri maybe Sat. Quality Inn Lake Park, same place as before. They did a reno on the hotel, it needed it. River should be at 260 tomorrow. 45 miles away the Suwannee is ripping at 5500, go figure. They are about equal in flow, both best to collect about 100 to 200. River higher than i want, may go way down and find a big shoal I scored well at on an over night kayak trip long ago. The Suwannee drains the Okeefenokee, a big catchment, slower to drain because of it's heavy foliage. It was hit by Irma and got filled up good. It also stays warmer longer. Have a fantastic trip jamesp!!! Find the new honey hole and scope out the best overnight trip and we will do it again next year for sure!
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fishnpinball
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Post by fishnpinball on Oct 4, 2017 7:28:34 GMT -5
hoping it works.
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melf77
having dreams about rocks
Member since July 2017
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Post by melf77 on Oct 5, 2017 4:34:05 GMT -5
Watching this thread, very interested to see what the results are.
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Post by MrMike on Oct 5, 2017 5:20:13 GMT -5
jamesp, what about using some lava rocks in the rotary? You do like time released grit.
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jamesp
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Post by jamesp on Oct 5, 2017 7:40:43 GMT -5
jamesp, what about using some lava rocks in the rotary? You do like time released grit. Pumice can be polluted with all kinds of impurities Mike. Namely some nasty silicates. May or may not be a problem. The source from various locations can be pure and free of hard silicates Just keep in mind when coarse grinding with chunks the grit never breaks down. Great for coarse grind. You have fresh sharp grit constantly even if small chunks are in the rotary. On the last coarse grit run I remove the chunks at clean out and roll 30 or 46 for about a week till it breaks down a lot to prep for finish. You can get away with leaving say AO 22 (basically chunks) as it simply rounds off and imparts a polish. From what I read pumice is very friable(their words) and will hopefully break down to 1 to 4 micron particles we need to polish our rocks. It may break down too fast and not remove say 220 or 500 scratches though. It may be a timing game. I am out of town, getting ready to ask wife to turn off vibe after 2.5 days this morning. I left it unattended. When I get back I will report.
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jamesp
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Post by jamesp on Oct 5, 2017 8:19:02 GMT -5
melf77 fishnpinballGarnet abrasive can be had in 270 to 300 grit. It will polish hard agate if left in the vibe. But it is softer of an abrasive than aluminum oxide. Garnet 300 is commonly used in filtration, can be had cheap. I tried it before on soft rocks and did not have good luck. May need to introduce ceramic media to help break it down.
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jamesp
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Post by jamesp on Oct 5, 2017 9:04:32 GMT -5
Seems like soft rocks would not only shape fast in coarse grind but also polish faster too.
My experience has been the opposite, hard rocks are first to achieve polish in a batch of agate jasper and coral. Coral is super hard and it always polishes quicker than a bit softer jasper in the same load. Every time. Slow as hell to shape, but fast to polish $&@/)!&/.
Slurry thickener may play a big role in polishing soft rocks. I would not discount that theory. To me, dry tumbling uses thick slurry. Basically the walnut shells or whatever is used is basically the slurry. Very padded. Some toothpaste is abrasive, to whiten your pearly's lol. Maybe some toothpastes would get er done. (Brain storming here). Maybe a visit to Sam's is in order. Some tooth pastes use pumice. Some use aluminum oxide/aluminum silicate compounds. Others. Hmmm At least the quality control is in place since it is used orally.
Toothpaste is a classic use of slurry, like it or not. It has all the traits of a slurry, lubricant and suspension agents. I could see squeezing a hole tube of tooth paste into a vibe. And it is designed to be mixed with water unlike petroleum based slurries that do not like to have water mixed with them. Certainly the FDA monitors the ingredients in toothpaste. Probably not a good idea to put silicon carbide in it. Teeth are very hard. Not sure what their Mohs are. But super hard ceramic fillings wear faster than teeth, think about it. Crowns are cut on a CNC diamond bit cutter. The ceramic they use is like Mohs 9. Hard and a tough ceramic.
Probably many types of abrasives in various brands of toothpaste. Remember that Colgate powder that came in a tin ?
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