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Post by Bob on Mar 8, 2021 17:11:55 GMT -5
I'm not expecting any of you to believe this message and I certainly can't blame you.
This is my 7th year of rotary tumbling. Several years ago I got so good at proper water and filling that my slurries are almost perfect every time. This comes with 8 barrels and doing something almost every evening. On rare occasions, I might have one on the too thick side but that can happen. It happens maybe 3-4 times per year. Heck, I even forget to add water almost that often!
Well, something REALLY WEIRD has happened. A week ago, my 40lb barrel had slurry so thick it could not be poured out. It was about the consistency of sheetrock compound and holding the rocks in place. Huh? So I had to pour in a lot of water, then carry the new EXTREMELY HEAVY barrel back and let it tumble overnight. Now it was okay. I figured oh well, something weird had happened that I can't figure out.
Then a few days later, I had two 20lb barrels due. Both of them had the same dang problem exactly! I had to do the water add and overnight again. Now, I'm really wondering at that point.
Then a few days later, last night, I had three 12lb barrels due. All of them had the same problem also! This means all barrels that have come due in 6 days or so have had the exact same super thick slurry. My rocks are just the same old misc. rocks I always tumble.
How is this even possible? Does anyone know if a city water supply can suddenly change in some way to cause this? The water looks and tastes just like always. I currently and always have drunk tap water and think it tastes great. Not only does this perplex me, but it also scares me a little bit. Is there some obvious explanation for this happening that I have overlooked?
The thickness of this slurry is so thick that were I to attempt to make it on purpose, I would probably have tried only putting in 1/2 the normal water level--something I have never done.
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lordsorril
freely admits to licking rocks
Member since April 2020
Posts: 766
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Post by lordsorril on Mar 8, 2021 17:19:24 GMT -5
Usually happens to me when I disintegrate a lower mohs rock in the tumble or I add too much grit and not enough water. It is a huge mess in the winter when I have no running water available...I have to scrape the rock paste out of the barrel.
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Post by parfive on Mar 8, 2021 17:26:22 GMT -5
When all these barrels are due, what is that, after a week?
Maybe take a peek in the next ones after a day or two or four and see if anything odd is developing.
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stefan
Cave Dweller
Member since January 2005
Posts: 14,095
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Post by stefan on Mar 8, 2021 19:34:51 GMT -5
My first thought was a soft rock (like maybe limestone?) But if it's happening to all stages at the same time, it has to be the water. No idea if it is more acidic, basic, harder, softer, more chlorine, less. If I had to go out on a limb I would guess softer, more acidic water, as it would accept more dissolved solids and attack more pH sensitive rocks.
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Benathema
has rocks in the head
God chased me down and made sure I knew He was real June 20, 2022. I've been on a Divine Mission.
Member since November 2019
Posts: 703
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Post by Benathema on Mar 8, 2021 20:57:20 GMT -5
If your big barrels are all coarse grind then I suspect there were a couple poor rocks that don't exist anymore. I don't know what I ground up recently but 1 day into tumbling I noticed the sound changed, more clanking, and same as you describe. Pretty much rocks cemented to the walls of the barrel with the center open like a donut hole, and a few stones in the middle banging around in the center. Diluted it and kept going.
I'm not convinced on the water. If it had become super acidic, you'd notice a taste. Maybe the pH is slightly different. We're not filling our barrels with concentrated hydrochloric or sulfuric acids, at least I hope.
I lean towards softer stones.
... Or... maybe you stumbled onto the holy grail combination of tumbling variables for maximum grinding. ;P
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electrocutus
spending too much on rocks
Member since October 2020
Posts: 331
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Post by electrocutus on Mar 9, 2021 9:05:30 GMT -5
maybe someone is playing a cruel joke on you and replaced your grit with cement mix :-) Is this happening with different grits or are all of them at the same stage?
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Post by Bob on Mar 9, 2021 10:59:37 GMT -5
Someone asked about a week, yes, 7 days is my normal run. All were coarse grind 50-60 except one was 80. I've been doing it this way for maybe 4 years. Last night, I nervously opened a 6lb barrel that was in 600. Whew--entirely normal slurry.
Then I opened a 20lb one again, one that had completed 7 days since this problem started. It happened AGAIN! I'm dying. I even remember adding more water than ever to it, almost 1/2" below the rocks.
I can't think of any variable that could explain this unless the water has changed. It's the same batch of grits. It's the same barrels. It's the same tumbler bases. It's the same material that I've been tumbling for years--various jaspers, agates, and cherts and a few but not many random beach rocks from Lake Superior and Orcas Island.
The 40lb barrel is due again tonight. If it happens with it again, out of desperation, I'm going to start lowering my material fill level from it's normal 70-75% which I've been running for years. I don't know what else to do. Actually, I just thought of one thing. Someone who posted above mentioned water ph. I suppose I could add some baking soda to see if anything changed. I normally only use it in batches of glass/obs to prevent gas blowouts.
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Post by HankRocks on Mar 9, 2021 11:52:26 GMT -5
Bob I think you need to eliminate the mix of rocks as the issue. Try tumbling a batch of pure agate with no other types. My own guess is that there are some very soft rocks in the batch that are going to slurry fast. One other thought, have you examined the grit you are using to be sure it's all SiC with no extra non-SiC mixed in?
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rockstock
spending too much on rocks
Member since April 2019
Posts: 472
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Post by rockstock on Mar 9, 2021 13:48:08 GMT -5
The random beach rocks sound like the answer.
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Post by Bob on Mar 9, 2021 16:37:06 GMT -5
The random beach rocks indeed can have a rind, or porosity that can soak up water I have learned. And there have been times when I've tumbled lots of them. But they are maybe only 10% of some of these batches. Not only that, but for 2-3 years now I scratch all collected rocks with a Mohs 7 pick. If it scratches and I think it's not just the weather rind, I discard it. This results in maybe 1/3 of all the material I collect on beaches getting discarded. I don't want to waste my time or money. Obviously, I could carry the pick in the field but many of the rocks are extremely dirty when I find them and I at least wash them well before examining and doing the scratch test.
The grit looks like it always does, just pure SC. I'm tumbling a lot of chert, which is extremely tough and solid silicified dolomite. Putting some in water and expecting anything to soak up would be like putting ball bearings in water. Also a lot of Cerro Pedernal chalcedony, and grey river chert from this part of US, various agates and bloodstone and just the usual misc. more or less. And the smalls, the quartz thumbnail size river chat I buy on eBay in quantity, is the same as always.
When the barrel is tumbled one more day with water added to that sheetrock compound-like slurry, I have noticed something. The texture of the watery slurry has a slight feel to it that is different. I've also noticed that when rinsing off my fingers, it takes a few more rubs in the water than usual. I guess I will also call the municipal water department and ask if anything has changed since mid-Febr. I do believe I will remember to add a bit of baking soda to each barrel for a while as a test.
There are 8 barrels currently, 1x40 lb, 2x20 lb, 4x 12 lb, and 1x6 lb. They are all on 7 day runs, but the 40lb is a 6 day run this time of year because grit gets used up faster. I'm not currently doing any glass/obs but it's normally a 8-9 day run because grit lasts longer. On average I have 1 or 2 barrels per evening to process, and since they aren't staggered perfectly sometimes up to 5 will be on some days and not some on some days.
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Post by parfive on Mar 9, 2021 16:56:30 GMT -5
Municipal water department answers one question.
Any water filter/softener systems in your house?
And you don’t live around Detroit, right?
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rockstock
spending too much on rocks
Member since April 2019
Posts: 472
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Post by rockstock on Mar 9, 2021 17:02:30 GMT -5
Here's thick lol
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Post by Bob on Mar 9, 2021 17:10:43 GMT -5
Municipal water department answers one question. Any water filter/softener systems in your house? And you don’t live around Detroit, right? No such devices or systems. And I live in Oklahoma and sure glad it's not Flint, Michigan!
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Post by greig on Mar 9, 2021 17:14:20 GMT -5
My two cents. It's the rocks. Something in there is grinding down quickly and making clay. I have had the same issue with self collected calcite, turquoise, garnet and fluorite. The solution is to forget about stage 1 and/or tumble for a shorter time. I really doubt the water is a problem. I bet if you run them again with bottled water that you will get the same result.
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Post by Bob on Mar 9, 2021 17:14:24 GMT -5
I imagine my rocks would look about the same if removed from the barrel. I don't do that though because rinsing off slurry like that from the rocks and cleaning the barrel too takes very long time. The easy way is just to add some water to the barrel, reclose it, and tumble it overnight. Then one can deal with it easily and quickly. I've had this work fine even with only 1" of air left. Still have to clean the lip and wash the gasket though before resealing which is irritating.
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Post by Bob on Mar 9, 2021 17:23:06 GMT -5
I just thought of something else that is different and may be related. My rinse water that I recycle is getting clearer faster from settlement.
I pour off rinse water into two 5 gal backets. The dirtiest one, that is the first pouroff after the first rinse, is where I get my water to put in next batch. The cleaner one is my best rinse water for final rinse of rocks in the mesh drain. At the end, I ladle from the dirty one to the clearer one to take the clearer one up to 1" from lip to get ready for next day. And that next day, the clearer one is not truly clear, but it's pretty decent rinse water though still foggy. If I leave on a trip of a week or more, it is sometimes truly clear when I get back because full settlement had occurred in a week w/o any disturbance or pouring anything in.
But I just now remembered that for a couple of weeks or so, that clearer bucket has been almost completely clear the next day! So something weird is going on. What I'm going to do tonight, is dump both buckets out, even though I've been using this method for almost 7 years. I'm going to refill them with totally new and unused water and *not recycle any rinse water* for a week to see if something different happens.
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stefan
Cave Dweller
Member since January 2005
Posts: 14,095
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Post by stefan on Mar 9, 2021 19:51:01 GMT -5
Ok this is just one other thought, and the only reason I mention it is it happened to me. Some of you local collected rock may not be as it seems. I found a deposit of really decent chert that I was very excited to tumble. It was hard and not all fractured and perfect for what I wanted. I set up a 3 Lb barrel with it and started to go. Yup it all turned to sludge after 1 week. I believe it was a module that was basically clay in the center with a thin crust of chert. I broke through the crust and that's all she wrote. Your slurry looks like clay, acts like clay (the way it sticks and settled out), and I bet it even smells like clay . I would hold off on the locally collected stuff until you can get to the bottom of this issue. I suspect something in your local stuff is not as it seems.
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Post by parfive on Mar 9, 2021 21:32:55 GMT -5
Water clearing up gets me thinking flocculant . . .
Aluminum sulfate is mentioned every year in the water quality report from the water company.
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Benathema
has rocks in the head
God chased me down and made sure I knew He was real June 20, 2022. I've been on a Divine Mission.
Member since November 2019
Posts: 703
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Post by Benathema on Mar 10, 2021 0:55:42 GMT -5
I'd say pick one variable at a time. Easiest ones first.
It's been a few years since I picked up distilled water, but I think it's somewhere near a buck a gallon.
Pick one type of rock, like these silicates, with minimal impurities such as plain quartz. these "quartz" SiO2 minerals like quartz and chalcedony shouldn't be reactive towards much of anything we deal with. Quartz cuvettes are used in spectroscopy for this reason (and other reasons).
I'm not sold on baking soda, unless it's neutralized before the barrel gets closed up. I'm still convinced acid-base reactions, or thermal decomposition of carbonate can lead to CO2 buildup and blow the barrel open.
Sulfates, chlorides, and iron compounds could be present in any number of rocks, even as trace impurities of other minerals. A little dance between them in solution could result in some of the flocculant compounds listed above. I don't think this is responsible for your thick slurry generation, just the clarification of the rinse water.
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USMC15
Cave Dweller
I feel like I just came out of the tumbler ...
Member since March 2021
Posts: 273
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Post by USMC15 on Mar 10, 2021 16:43:29 GMT -5
Well, I think you can pass the slurry off as sculpture clay and get a few bucks.
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