poprocks
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Post by poprocks on Mar 21, 2021 22:23:04 GMT -5
I’ve read through a few articles on here and websites about thickening slurry to help with the grit sticking to rocks in the coarse grinding stage. I’m really curious about this, I’ve read that you can use cat litter (clay), sugar, mud and/or river rocks that produce their own slurry thickeners. I just have no clue how they work and what impacts each have on the rocks and the slurry itself?
That kind of had me thinking could I use crushed chalk or egg shells? Or would they impact the finishing on the rocks by say like producing a film on them after rinsing the coarse grit from the rocks. Would anyone happen to know? I would assume that the chalk or egg shells wouldn’t do any damage to the rocks or create a film but I wanted to know if anyone had tried it?
Also I read in a few other threads on here that say you can reuse the grit cement from previous tumbles as well as reuse grit that hasn’t broken down in tumble cycles? Could someone break that down for me into maybe a more detailed process for how to do that to be reused into a rotary tumbler? I think I have a basic understanding but before I try anything and possibly mess something up I wanted to ask, obviously I’ll keep doing research but I figure people here on this forum would have personal experience that maybe websites wouldn’t.
I’m still very fairly new and I’m currently only on my first and second batch of tumbles in a rotary Lortone 33B tumbler, one is a batch of unknown rocks that are doing really well so far and the second is a small batch of rose quarts with a peice of amethyst and about 30% ceramic media, if you want to know more about those please feel free to ask but my question is more directed at the knowledge of slurry thickeners and reusing grit.
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jamesp
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Post by jamesp on Mar 22, 2021 3:28:01 GMT -5
I use red clay from my yard poprocks. It is sticky, slick and makes the slurry heavy. It does stick the grit to the rocks. It also lubricates, pulls the rocks against each other and by making the slurry heavier it 'floats' the grit better. But can become too thick and hinder tumbling action. Welcome to RTH.
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poprocks
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Post by poprocks on Mar 22, 2021 3:43:33 GMT -5
I use red clay from my yard poprocks. It is sticky, slick and makes the slurry heavy. It does stick the grit to the rocks. It also lubricates, pulls the rocks against each other and by making the slurry heavier it 'floats' the grit better. But can become too thick and hinder tumbling action. Welcome to RTH. Thank you so much for replying! I’m thinking I might start with clay as a first option for thickening my slurry
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jamesp
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Post by jamesp on Mar 22, 2021 4:10:33 GMT -5
You may have to experiment to get a milk shake consistency. Best to adjust the clay/water mix before adding grit. If the slurry is too thick the rocks can be washed off, start over and amount of clay reduced. Measure amount of clay so it can be dosed for best consistency/thickness for the future. My particular clay - 2 cups for a 7 pound barrel. Yours may be different as it depends on the clay.
I only use clay for step 1 and 2. It takes the longest. i.e. you must clean out in step 1 and add coarse grit 4 to 8 times till rocks are rounded. Avoid clay for the finish steps because it usually has abrasive sand in it.
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poprocks
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Post by poprocks on Mar 23, 2021 6:17:20 GMT -5
You may have to experiment to get a milk shake consistency. Best to adjust the clay/water mix before adding grit. If the slurry is too thick the rocks can be washed off, start over and amount of clay reduced. Measure amount of clay so it can be dosed for best consistency/thickness for the future. My particular clay - 2 cups for a 7 pound barrel. Yours may be different as it depends on the clay. I only use clay for step 1 and 2. It takes the longest. i.e. you must clean out in step 1 and add coarse grit 4 to 8 times till rocks are rounded. Avoid clay for the finish steps because it usually has abrasive sand in it. Jamesp thank you! I’ll definitely experiment a little before I add grit, what kind of clay do you use? I read that I could use clay cat litter? I’ve been doing alot of reading and researching I think I have an idea of what kind of consistency I’m looking for, I wanted to ask though if there was any other way I could look into thickening the slurry for the pre-polish and polish stage so the polishes would stick better? Other than sugar and syrup because I don’t want to risk anything getting into the mix and possibly fermenting
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jamesp
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Post by jamesp on Mar 23, 2021 6:51:49 GMT -5
There are many different clays. I suggest practicing with the clay nearest you. Mine is iron/sand rich kaolin. For a 12 pound load it requires 4 cups for 8 recharges of coarse grit during step 1 on average. 32 cups is a lot of clay. But that is dialed in for my backyard clay, yours may be different.
I only use sugar in the vibe. 2 days sic 500, 3 days AO 220, 1 day AO polish. Fermenting ? Others use Borax, that may suit you.
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stefan
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Post by stefan on Mar 23, 2021 18:14:37 GMT -5
I reuse slurry all the time. Here how it works. I dump the barrel into a bucket. Add water and pull out the rocks (to be cleaned and sorted) then I let the mix settle for a few minutes (the heavier particles will sink fastest) Pour off the water and the top layer of lighter material. Let the remaining mud dry and store it for use on the next tumble. I usually add about two or three teaspoons of this dried mud for every pound of rock (depending on barrel size and what stage I'm in). THe really nice thing is that I'm recycling the heavier stuff and pouring away the lighter stuff so I just end up with a neat perfect amount every time (I have been doing this for long time so I have am good feel for how much to pour off). Also if you run out of grit (sin of sins) you can still run with just the old mud until your next grit shipment shows up! (not that this is something I have had to do on occasion!). One word of caution!!! When you dump the dried mud into the barrel and add water it will literally pop and explode! Not dangerous but I have had hunks of mud pop out of the tumbler and hit me. To avoid that I add the mud, then a layer of rocks, then fresh grit, then last is the water. You can hear the old grit pop and crackle!
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itusuallyworks
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Post by itusuallyworks on Mar 25, 2021 16:05:03 GMT -5
I have been doing the same thing as stefan, I save my old grit in a plastic tub and do 5 runs on the tumbler using the old stuff then course and so on and so on ...not sure if it really works but I am incredibly "frugal" ( See cheapskate in the dictionary) and want to get more than one use out of it.
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jamesp
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Post by jamesp on Mar 26, 2021 9:42:32 GMT -5
A note on slurry:
Muddy water is used to 'float' well drillings up and out of bore hole. To make heavy muddy water well drillers use ground up barite rock to mix in water.
"BARITE (Barium Sulfate) with the chemical formula of BaSO4. is used as a weighting agent in all types of drilling fluids. Application of barite
• Increase mud density up to 21 lb/gal (2.5 g/cm3)"
So a barium slurry can weigh 21 pounds per gallon verses 8.3 pounds per gallon of clean water. If any one has picked up barium(a common rock) they know how heavy it is.
The clay I use is a felspar so I have a felspar slurry for the most part. Felspar is not as dense as barite but still quite dense.
a 1 centimeter cube of agate weighs 2.7 grams a 1 centimeter cube of barium weighs 4 grams a one centimeter cube of silicon carbide weighs 3.9 grams. This is why it sinks fast.
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poprocks
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Post by poprocks on Mar 26, 2021 21:20:08 GMT -5
Thank you all so much! You answered a lot of questions I couldn’t quite find answers for no matter where I looked or how far back I went, I appreciate all the help! I’ll definitely play around and work out my own methods and who knows maybe I’ll be coming back to this thread with another technique you guys haven’t seen! (though I doubt that) ahaha. I definitely feel like I have a better understanding now
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jamesp
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Post by jamesp on Mar 27, 2021 7:00:30 GMT -5
Thank you all so much! You answered a lot of questions I couldn’t quite find answers for no matter where I looked or how far back I went, I appreciate all the help! I’ll definitely play around and work out my own methods and who knows maybe I’ll be coming back to this thread with another technique you guys haven’t seen! (though I doubt that) ahaha. I definitely feel like I have a better understanding now For general purpose entry level hobbyists the slurry concept is not mentioned in tumbler manufacturer's instructions perhaps due to the fact that it introduces more complexity. It does take some time to dial in the right slurry consistency when adding a thickener. Nice to have an awareness of it as an option but not necessary to successfully tumble rocks to a fine polish. Good luck with your tumbling career.
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Post by Bob on Apr 13, 2021 14:22:17 GMT -5
The outcome of what I'm about to say probably produces same result as stefan's method. An easy way to dial in the slurry consistency is to reuse some of the prior slurry. I've never measured how much I use, but my guess would be 5-10% and closer to 5 than to 10. There are two ways to do this.
On larger barrels in which I reach in and pull out the rocks, such as 20lb and 40lb barrels, this is done by leaving about 1" of slurry in the bottom. On smaller barrels such as 6lb and 12lb, I pour the entire contents into a rinse colander so that would not work. So after recharging I pour back in some of my dirtiest water, which is thicker than new water and the end result is about the same.
If, after one week, doing the above, vs not doing it and just using the correct amount of water in the beginning produces the exact same perfect slurry, they why does this topic matter?
I'm not entirely sure myself. Some of us think that with clean new water, it probably takes a few days for a slurry to develop, judging from the sound of our tumblers. Doing the other way means the water is thicker from the very first rotation, and might add a bit more cushioning to the load and lesson some damage. Whether any of that is true of not is not known to me.
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Post by HankRocks on Apr 13, 2021 16:12:01 GMT -5
I use slurry for two reasons, to protect certain rocks and to help suspend heavier grits throughout the tumbling load. Suspension is really only necessary for the larger grit sizes, 30, 60, 46/70, 80, 220 SiC, etc. Also the 80 AO. The finer grits 500, 600 and Polish really don't need help with suspending in the Load, they are self suspending.
For Protection, Loads of Quartz, Obsidian do better in my book with extra slurry as it helps prevent frosting especially in the Pre-Polish and Polish stages.
I save all of my slurries and keep them separated; SiC under 220, 600 SiC, AO - Pre-Polish, AO Polish. Then use about 2 cups in a 15 pound barrel.
Anyway, that's my process and it seems to work for me.
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Post by Bob on Apr 13, 2021 16:32:54 GMT -5
"Suspension is really only necessary for the larger grit sizes, 30, 60, 46/70, 80, 220 SiC, etc."
Hankrocks, so glad you mentioned and I agree, though I usually don't bother with it on 220.
It's weird how plastic pellets and adding a bit of "starter" slurry contradict each other. That's not a good way of saying what I'm trying to say. I use plastic pellets starting at 220 and finer grits, if I feel the need to add some extra cushioning. But, plastic pellets have not worked for me at all at grits larger than 220, so the extra slurry starter is the solution.
Years ago, if a coarse grind load at 50, 70, 80 etc had something that I treasured in it--something I really wanted to minimize any banging on because it was a rare piece--I would add some plastic pellets. After a normal week of processing, there was some strange results. The slurry would be watery and thin and lots of grit was still left, and not much grinding had taken place! I have zero idea on why that was, but I think it happened *every single time* so I stopped putting plastic pellets in anything larger than 220.
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oldtimer
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Post by oldtimer on May 7, 2021 18:01:58 GMT -5
Has anyone looked at various grits and dried "slurry" with a microscope to see what is happening at various stages? I did a search on "microscope" and came up blank. I have a microscope lab that I use for prospecting and thought I might do some research on the fate of grit and the makeup of slurry. But if it has been done already I can save some time by looking at what someone on this forum has done. I just had a very brief look at a bit of dried slurry from 60/90 run and it seems to have quite a bit of grit left in it.
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quartzilla
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Post by quartzilla on May 7, 2021 19:40:05 GMT -5
Has anyone looked at various grits and dried "slurry" with a microscope to see what is happening at various stages? I did a search on "microscope" and came up blank. I have a microscope lab that I use for prospecting and thought I might do some research on the fate of grit and the makeup of slurry. But if it has been done already I can save some time by looking at what someone on this forum has done. I just had a very brief look at a bit of dried slurry from 60/90 run and it seems to have quite a bit of grit left in it. . oldtimer that’s a good idea. Here is another idea: has anyone tried dropping small pieces of feldspar into their rough? Or even slate? I thought feldspar would be good since it breaks down into common clays and the hardness is kinda high and could carry further?
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Post by HankRocks on May 8, 2021 5:53:03 GMT -5
Has anyone looked at various grits and dried "slurry" with a microscope to see what is happening at various stages? I did a search on "microscope" and came up blank. I have a microscope lab that I use for prospecting and thought I might do some research on the fate of grit and the makeup of slurry. But if it has been done already I can save some time by looking at what someone on this forum has done. I just had a very brief look at a bit of dried slurry from 60/90 run and it seems to have quite a bit of grit left in it. Makeup of slurry and how much residual grit is left is a product of 4 main factors; Type of load, length of run, grit size, and amount of grit used. This applies mostly to the first stage. I use 3 different grit sizes for my coarse runs, 80 SiC, 60-90 SIC, 46-70 Sic. For a load of plain agates/jasper/pet wood I usually go with 46-70, sometimes 60-90 with re-charges every 3 days. 3-4 days after the last recharge is cleanout. I almost never see any grit close to the original size, it's all been broken down to probably smaller than 220. I also use this approach with runs with a 1 to 4 pound large. These types of runs are a grit crushers especially one with a large included. If I am tumbling a load of Pre-forms or large slabs I add a good bit of smalls to the load that along with the added slurry protects better. For these runs I use 80 SiC and I will run for 9 tp 10 days. When I opened after 7 days there was still a bit of original grit left. That makes sense to me as there are less big rock to big rock grit breaking encounters. I also go with a bit less grit in my runs than some I have seen. For me a good run is complete when all of the starter grit is broken down 2 or 3 times finer. I do keep my slurry segregated into 3 types, 220 SiC and larger, 600 SiC, and AO, 80 or 500. Even though I am not in the "soap and scrub after every stage" camp, I do take reasonable precautions, rinse with a good spray and keep slurries separated is about as far as I will lean towards that process. I usually fine tune most runs depending on the mix of rocks, how much grit and size of grit, how full to load the barrel, how much slurry, how long to run. These can all vary and the only way to really learn is by experience. What feels right. It's much like cooking a soup or a stew, many different paths to a well prepared bowl. Same with rocks. Bon appetit!!
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stefan
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Post by stefan on May 8, 2021 6:30:37 GMT -5
"Suspension is really only necessary for the larger grit sizes, 30, 60, 46/70, 80, 220 SiC, etc." Hankrocks, so glad you mentioned and I agree, though I usually don't bother with it on 220. It's weird how plastic pellets and adding a bit of "starter" slurry contradict each other. That's not a good way of saying what I'm trying to say. I use plastic pellets starting at 220 and finer grits, if I feel the need to add some extra cushioning. But, plastic pellets have not worked for me at all at grits larger than 220, so the extra slurry starter is the solution. Years ago, if a coarse grind load at 50, 70, 80 etc had something that I treasured in it--something I really wanted to minimize any banging on because it was a rare piece--I would add some plastic pellets. After a normal week of processing, there was some strange results. The slurry would be watery and thin and lots of grit was still left, and not much grinding had taken place! I have zero idea on why that was, but I think it happened *every single time* so I stopped putting plastic pellets in anything larger than 220. I had the same issue with plastic pellets! I never use them in anything courser than 500 grit as they actually slow down the action. For me it was Apache Tears. I wanted to be so careful with them that I cushioned the 120/220 run and was shocked that after 2 weeks I still had little breakdown in the grit and a very watery thin slurry and most of the grit remaining. I thought I was crazy!
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Post by rmf on May 8, 2021 15:25:50 GMT -5
poprocks I have never been a big fan of adding thickners. I start with 46-70 within 3 days I have a thick mud and the sound in the barrel is much quieter. when I wash out the coarse grit I was over a 5 gal bucket or wheelbarrow and the coarse grit settles out. I pour off the muddy water and wash the stones until the water is clearish. then go to the next grit. Set the coarse aside until the next rough batch. The same can be done with 220 Grit but the speed of the water will float a lot of the grit out with the mud. For 3LB tumblers it is not worth it to try and save the 220 grit.
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jamesp
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Post by jamesp on May 9, 2021 5:00:45 GMT -5
The problems I had waiting for a slurry or not using a slurry thickener in ALL rotary steps 1-2-3-4(sic30,sic220,ao500,polish) when tumbling glass, obsidian, some crystalline quartz rocks was(possible) frosting in any one of those 4 steps.
The frosting could occur in as fast as one hour. That's why I added thickener at start. Never roll without protection. Especially step 2-3-4.
If the frosting occurred in step 2-3-4 you had to start over with step 2(sic220) to remove the frost.
If the frosting occurred in step 1, the step 2(sic220) would usually remove it.
Clay thickener did fine in steps 1-2, but it had silica sand in it and scratched the crystalline quartz rocks and glass in step 3-4 so I thickened with (lots) of sugar in steps 3-4.
Got tired of buying 25 pound bags of sugar for the step 3-4 in rotaries and bought a vibe for steps 2-3-4. And used sugar in the vibe but at a much lower rate(like 1 cup vibe run verses 10+ cups per rotary run).
Anyway, sensitive materials like glass and obsidian will test the conditions in your rotary(and vibe). The load is ruined(frosted) in a matter of an hour or a few hours if conditions(in my case slurries) are not favorable for the entire 24 to 28 days it took to do a load of glass start to finish. 26 days = 624 hours. Lot's of hours to mess the load up.
Favorable conditions = higher polishes. Even when much harder rocks are involved. Poor conditions = lower polishes. Too much impacting, banging. Even for short periods.
Clay and sugar base slurries are reliable. Especially **sugar base slurries. Clays break down to finer clays. Clays vary. Felspar based clays(kaolin clay) are the Cadillac clays for slurries because they are composed of platelet(colloidal) particles. Kaolin clay is what is used in paint. Yea, a bucket of paint is basically a bucket of wet(colloidal) clay and dye and a few other additives. The clay serves as 'body' and suspension for the color additives. So kaolin clay is totally valuable for paint and abrasive suspensions and dozens of other mixtures like a lady's make up. Yep, most lady's have smeared clay on their beautiful faces and don't even know it.
** Sugar base slurries are affected by varying temperatures. Thinner when warm, thicker when cold.
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