gnuuser
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Post by gnuuser on Aug 4, 2019 9:00:47 GMT -5
Hi, all.
I have a question about preventing sludge at the bottom of barrels. Why it happens is something of a mystery to me. I always make sure that I put water in the barrels before adding grit to make sure that I’m not washing the grit to the bottom of the barrel. Then, I quickly close the barrel and rush it over to the tumbler and put it on immediately. I rarely pull the barrels off the machine, but if I do, I lay them on their sides. Still, every now and then, I get a failed tumble with all of the grit compacted at the bottom of the barrel.
This happened to me this week. I opened two barrels, expecting a nice slurry, and both barrels had compacted grit in the bottom of the barrel. So, I threw it all out and started over, this time shaking the barrels madly as I rushed over to the tumbler.
Is there some magical incantation I need to chant during the process to prevent this from happening?
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Post by captbob on Aug 4, 2019 10:40:51 GMT -5
*sigh* - but it is a good and reasonable question.
There is no "compacted sludge at the bottom of the barrel" when you are running the barrel. Especially from a fresh run start.
That "compacted sludge" gets there when you stop your run and set the barrel upright to open the lid. YES, it happens that fast! I'd bet 15 to 30 seconds is MORE than enough time to create what you are finding.
ETA: Welcome to the forum! (really was a good question, just not the issue you might believe it is.)
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gnuuser
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Post by gnuuser on Aug 4, 2019 11:24:31 GMT -5
CaptBob,
Thanks very much for your reply.
The reason I’m so confused is that I don’t remember touching any of my barrels all week. I certainly didn’t open any of them all week. But, if that’s the only way this can happen, I must have done something with them. I know that standing them up could cause this, but didn’t realize that it could happen almost instantly.
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gnuuser
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Post by gnuuser on Aug 4, 2019 11:31:33 GMT -5
By they way, I should probably clarify that the sludge in this case was mostly unused coarse grit. It was obvious that this happened very early on in the week. When this has happened before, there was more sludge and the the grit was worn down, so it was clear that it was working until I messed with the barrels. In this case, I couldn’t figure out what happened.
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Post by captbob on Aug 4, 2019 11:39:24 GMT -5
No sir, coarse grit can remain coarse much longer than a week. I really doubt that you did anything wrong. This build up at the bottom simply happens when you set the barrel on end. In a quickness!
No need to toss that grit out, use it again if it is still good. Tumbling is a learning experience for sure and you will see that the first thing that you should do is toss any instruction books in the trash!
You'll get it!!
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gatorflash1
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Post by gatorflash1 on Aug 4, 2019 11:43:31 GMT -5
I probably have a bunch of dumb questions here but I'll ask you anyway.
Are you using the proper amount of grit, or are you overloading it? That would be an easy problem to solve.
Are you using tumbling media like ceramics to keep the brew stirred up? That would be another easy problem to solve?
Are you using any sugar, etc. with your batch that might cause this? You might try adding a spoon of Ivory soap flakes.
Are you waiting long enough to give the grit time to do it's work? Easy problem to fix.
I use 30 or 60 course grit for my step 1 and will let it tumble for two or three weeks to be sure it is well broken down and has done it's work. I don't know if you are giving the tumbler enough time to work.
Just some dumb questions. I hope you find the solution and if you do you let us know what it was.
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 11:44:09 GMT -5
I disagree with Captbob about this being a settling issue versus a compacting issue. I had this happen recently 2 different times and both after a full week of running. It was obvious that the grit hadn't settled after taking off the tumbler because I had done pre grinding on some rocks and the stones were just as rough as before. There was no slurry to speak of and In another barrel that it happened with was a batch of stones close to moving onto next stage but after week of tumbling the surface of stones was rough to touch where previously smooth. Both times I was breaking in some small ceramics and bad filled barrel by first putting all ceramics in barrel, then rocks, grit and water . Both times the grit was stuck at bottom with majority of ceramics stuck with it. After second time this happened I refilled barrel with same load of rocks and ceramics as before but loaded ceramics last and used same amt of grit and water. This time I added water first and then grit. Checked barrel after 5 days instead of 7 and had no issue and almost full grit breakdown. It simply just couldnt have been an issue of grit settlement after removing barrel from tumbler as I uses exact same amt of everything and only changed how I loaded barrel. And after shorter run time than when had issue I had full breakdown of grit and zero compacting. I know I'm new to tumbling and have read on here before that there is no compacting just settling. But that's exactly why I used same recipe to test this theory and am convinced it was my filling the barrel with small ceramics first, then rest of stones, then grit and water. Just my experience so take it for what you will
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Post by captbob on Aug 4, 2019 12:05:13 GMT -5
okay... now I'm curious how this compacted/settled grit (or whatever you want to call it) could form on the "bottom" of a running tumbler.
When running, the bottom is a side wall of the interior of the barrel. Maybe I don't understand physics or gravity so well, but how does this concoction accumulate on the side wall of a moving barrel?
Have you ever had it happen on the lid end? Where when you open the barrel there is this mass of grit/ceramics on the top rather than the bottom, or is it always on the bottom?
Even misloading the barrel and adding the water after the grit instead of before shouldn't result in such a mass of grit being stuck to the bottom.
But, I could be wrong, I'm kinda new to this tumbling stuff ...
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gnuuser
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Post by gnuuser on Aug 4, 2019 12:21:04 GMT -5
I probably have a bunch of dumb questions here but I'll ask you anyway. Are you using the proper amount of grit, or are you overloading it? That would be an easy problem to solve. Are you using tumbling media like ceramics to keep the brew stirred up? That would be another easy problem to solve? Are you using any sugar, etc. with your batch that might cause this? You might try adding a spoon of Ivory soap flakes. Are you waiting long enough to give the grit time to do it's work? Easy problem to fix. GatorFlash1,
I use 2 tablespoons of grit per pound of rocks. Sometimes I use ceramic media, if I don't have enough small stuff to put in. I don't use anything but grit and water except when washing rocks/barrels in preparation for polishing.
9 out of 10 tries, everything turns out just fine, but 1 out of 10 tries, I unexpectedly get this cement-on-the-bottom of the barrel thing.
It must be what CaptBob says. He's right... it never happens at the lid end, so I MUST be standing them up at some point and not realizing it. The only other thing I've found is that it happens if I put grit in first, and wash it down with water. It causes the cement thing every time. It's the times like this when I do all the right things and it happens anyway that I can't figure out!
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Post by rockpickerforever on Aug 4, 2019 13:04:28 GMT -5
I disagree with Captbob about this being a settling issue versus a compacting issue. I had this happen recently 2 different times and both after a full week of running. It was obvious that the grit hadn't settled after taking off the tumbler because I had done pre grinding on some rocks and the stones were just as rough as before. There was no slurry to speak of and In another barrel that it happened with was a batch of stones close to moving onto next stage but after week of tumbling the surface of stones was rough to touch where previously smooth. Both times I was breaking in some small ceramics and bad filled barrel by first putting all ceramics in barrel, then rocks, grit and water . Both times the grit was stuck at bottom with majority of ceramics stuck with it. After second time this happened I refilled barrel with same load of rocks and ceramics as before but loaded ceramics last and used same amt of grit and water. This time I added water first and then grit. Checked barrel after 5 days instead of 7 and had no issue and almost full grit breakdown. It simply just couldnt have been an issue of grit settlement after removing barrel from tumbler as I uses exact same amt of everything and only changed how I loaded barrel. And after shorter run time than when had issue I had full breakdown of grit and zero compacting. I know I'm new to tumbling and have read on here before that there is no compacting just settling. But that's exactly why I used same recipe to test this theory and am convinced it was my filling the barrel with small ceramics first, then rest of stones, then grit and water. Just my experience so take it for what you will I have NEVER had this happen to me, and I am not particular when loading grit and water. I do measure the grit out, but not the water. I just pour that right in after the grit, and fill until it is at the he proper level. Of course, I only use my rotary tumbler for coarse grit (30), and I continue to add more every few days, refreshing it with sharp grit. Never had a compaction problem, or unused grit it the bottom of the barrel. I let it run a week or three to let it break down to a fine powder. A good wash, to remove any larger pieces still stuck in holes, then on to finer grit and polish in the vibe. Just my two cents.
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 13:49:29 GMT -5
okay... now I'm curious how this compacted/settled grit (or whatever you want to call it) could form on the "bottom" of a running tumbler. When running, the bottom is a side wall of the interior of the barrel. Maybe I don't understand physics or gravity so well, but how does this concoction accumulate on the side wall of a moving barrel? Have you ever had it happen on the lid end? Where when you open the barrel there is this mass of grit/ceramics on the top rather than the bottom, or is it always on the bottom? Even misloading the barrel and adding the water after the grit instead of before shouldn't result in such a mass of grit being stuck to the bottom. But, I could be wrong, I'm kinda new to this tumbling stuff ... I agree that it doesnt make sense but it also doesnt make sense that after a full week of tumbling that 90-95% of the grit would remain unused, rocks roughed up and no slurry to form. Cant speak to it forming on the lid as it's impossible to load a barrel in such a manner. I only use 1 tbsp per pound of rock and this was in a 3lb lortone barrel. I easily had 2.5 tblspoons of unused grit. And the rocks all had a rougher feel as tho rocks were just tumbling around together without grit. If you were to run an experiment the the barrel tumbling would be the constant and the contents of barrel and loading of barrel would be the variables. But when running identical amts of grit, rock and water the variable would be the loading of the barrel. When I did so with the only variable being the loading of the barrel the outcome was different which would led me to my conclusion. Anyhow,im Not trying to prove anyone wrong and not smart enough to speak to the science aspect of my conclusion. Only going off my personal experience in hope to shed light on potential cause of issue.
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 13:58:49 GMT -5
I probably have a bunch of dumb questions here but I'll ask you anyway. Are you using the proper amount of grit, or are you overloading it? That would be an easy problem to solve. Are you using tumbling media like ceramics to keep the brew stirred up? That would be another easy problem to solve? Are you using any sugar, etc. with your batch that might cause this? You might try adding a spoon of Ivory soap flakes. Are you waiting long enough to give the grit time to do it's work? Easy problem to fix. GatorFlash1,
I use 2 tablespoons of grit per pound of rocks. Sometimes I use ceramic media, if I don't have enough small stuff to put in. I don't use anything but grit and water except when washing rocks/barrels in preparation for polishing.
9 out of 10 tries, everything turns out just fine, but 1 out of 10 tries, I unexpectedly get this cement-on-the-bottom of the barrel thing.
It must be what CaptBob says. He's right... it never happens at the lid end, so I MUST be standing them up at some point and not realizing it. The only other thing I've found is that it happens if I put grit in first, and wash it down with water. It causes the cement thing every time. It's the times like this when I do all the right things and it happens anyway that I can't figure out!
If has nothing to do with how barrel is loaded then standing the barrel up anytime between start and finish would have no negative effect, only after completed would it make difference. You say that it happens everytime you add grit before water, that would make me assume it has to do with loading of barrel.
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 14:11:11 GMT -5
I disagree with Captbob about this being a settling issue versus a compacting issue. I had this happen recently 2 different times and both after a full week of running. It was obvious that the grit hadn't settled after taking off the tumbler because I had done pre grinding on some rocks and the stones were just as rough as before. There was no slurry to speak of and In another barrel that it happened with was a batch of stones close to moving onto next stage but after week of tumbling the surface of stones was rough to touch where previously smooth. Both times I was breaking in some small ceramics and bad filled barrel by first putting all ceramics in barrel, then rocks, grit and water . Both times the grit was stuck at bottom with majority of ceramics stuck with it. After second time this happened I refilled barrel with same load of rocks and ceramics as before but loaded ceramics last and used same amt of grit and water. This time I added water first and then grit. Checked barrel after 5 days instead of 7 and had no issue and almost full grit breakdown. It simply just couldnt have been an issue of grit settlement after removing barrel from tumbler as I uses exact same amt of everything and only changed how I loaded barrel. And after shorter run time than when had issue I had full breakdown of grit and zero compacting. I know I'm new to tumbling and have read on here before that there is no compacting just settling. But that's exactly why I used same recipe to test this theory and am convinced it was my filling the barrel with small ceramics first, then rest of stones, then grit and water. Just my experience so take it for what you will I have NEVER had this happen to me, and I am not particular when loading grit and water. I do measure the grit out, but not the water. I just pour that right in after the grit, and fill until it is at the he proper level. Of course, I only use my rotary tumbler for coarse grit (30), and I continue to add more every few days, refreshing it with sharp grit. Never had a compaction problem, or unused grit it the bottom of the barrel. I let it run a week or three to let it break down to a fine powder. A good wash, to remove any larger pieces still stuck in holes, then on to finer grit and polish in the vibe. Just my two cents. I never used to pay attention to how I loaded the barrel before and the first time it happened I had no idea why. I only thought about it After the second time because I specifically put the ceramics in the empty barrel before loading it with rocks bc they were new and going to be used in lot o tumbler so I wouldnt forget to add them in to mix. When I saw that it was all the ceramics and grit at bottom that was the only thing I could come up with to try and change so didnt happen again. Figured that given how little space there is between a pile of same small size ceramics that the coarse grit filled the small spaces not leaving any space between, water wasnt sufficiently able to penetrate through the layer to mix it up and tumbling of barrel helped to hold it in place. But I have no idea how fact based that thinking is
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 14:32:12 GMT -5
Captbob, if the cause of issue were to be how the barrel contents were loaded then the accumulation of grit would be happening before placing on tumbler. A 3lb barrel is only 4inches diameter and spinning at 60rpms, a full rotation doesnt take but a second. The "cemented" grit does not easily wash out of the barrel when this happens, more like has to be scooped out. So if that's in bottom of a barrel when spinning 60rpms I would think its feasible that it would stay put. As it's not entirely on a side wall when barrel is spinning. If the layer is say .5 or .75 inches thick then a portion of that layer would be spinning while the portion that's not would act as force against the portion spinning from tumbling and instead keep it stuck going round and round instead of tumbling like the rocks do. Wouldnt it be same principle as why barrels overfilled do not efficiently tumble rocks due to the lack of ability to rise and fall over eachother.
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Post by HankRocks on Aug 4, 2019 16:06:57 GMT -5
Captbob, if the cause of issue were to be how the barrel contents were loaded then the accumulation of grit would be happening before placing on tumbler. A 3lb barrel is only 4inches diameter and spinning at 60rpms, a full rotation doesnt take but a second. The "cemented" grit does not easily wash out of the barrel when this happens, more like has to be scooped out. So if that's in bottom of a barrel when spinning 60rpms I would think its feasible that it would stay put. As it's not entirely on a side wall when barrel is spinning. If the layer is say .5 or .75 inches thick then a portion of that layer would be spinning while the portion that's not would act as force against the portion spinning from tumbling and instead keep it stuck going round and round instead of tumbling like the rocks do. Wouldnt it be same principle as why barrels overfilled do not efficiently tumble rocks due to the lack of ability to rise and fall over eachother. Ok, I have emptied maybe 150 loads from the 1st stage in the last 4 years and I have never had this issue. I always add the grit and slurry before the water. You do seem to use a lot more grit per pound than I do. For my 15 pound barrel I usually add about 6 or 7 tablespoons of grit and about 2 to 2-1/2 cups of slurry. After 3 to 4 days depending on the type and shape of the rocks I do a re-charge with maybe 4-1/2 to 5 tablespoons of grit. After 10 to 12 days I do a clean out and almost always have a good slurry. The recharge allows me the opportunity to see how the slurry is doing and to check it's level, adding or pouring off water/slurry as needed. If I set the barrel on the bench and open it early there are still grit particles suspended and clinging to the rocks, slurry doing it's job. Just curious how much slurry you are creating on a normal run, and the makeup of your load. For a well rounded material and a well balanced mixture of sizes the grit should breakdown and grind quicker than a load of jagged and not enough smalls load. There are not enough rock to rock contacts per rotation on the later to breakdown and grind as quickly, much reduced slurry creation. I would be curious to see a typical load of rocks you run in the first stage.
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Wooferhound
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Post by Wooferhound on Aug 4, 2019 16:11:31 GMT -5
Sounds like too much water. In Stage 1 the water should be well below the level of the rocks.
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 16:27:33 GMT -5
Captbob, if the cause of issue were to be how the barrel contents were loaded then the accumulation of grit would be happening before placing on tumbler. A 3lb barrel is only 4inches diameter and spinning at 60rpms, a full rotation doesnt take but a second. The "cemented" grit does not easily wash out of the barrel when this happens, more like has to be scooped out. So if that's in bottom of a barrel when spinning 60rpms I would think its feasible that it would stay put. As it's not entirely on a side wall when barrel is spinning. If the layer is say .5 or .75 inches thick then a portion of that layer would be spinning while the portion that's not would act as force against the portion spinning from tumbling and instead keep it stuck going round and round instead of tumbling like the rocks do. Wouldnt it be same principle as why barrels overfilled do not efficiently tumble rocks due to the lack of ability to rise and fall over eachother. Ok, I have emptied maybe 150 loads from the 1st stage in the last 4 years and I have never had this issue. I always add the grit and slurry before the water. You do seem to use a lot more grit per pound than I do. For my 15 pound barrel I usually add about 6 or 7 tablespoons of grit and about 2 to 2-1/2 cups of slurry. After 3 to 4 days depending on the type and shape of the rocks I do a re-charge with maybe 4-1/2 to 5 tablespoons of grit. After 10 to 12 days I do a clean out and almost always have a good slurry. The recharge allows me the opportunity to see how the slurry is doing and to check it's level, adding or pouring off water/slurry as needed. If I set the barrel on the bench and open it early there are still grit particles suspended and clinging to the rocks, slurry doing it's job. Just curious how much slurry you are creating on a normal run, and the makeup of your load. For a well rounded material and a well balanced mixture of sizes the grit should breakdown and grind quicker than a load of jagged and not enough smalls load. There are not enough rock to rock contacts per rotation on the later to breakdown and grind as quickly, much reduced slurry creation. I would be curious to see a typical load of rocks you run in the first stage. I dont think it was solely the grit and then water combo that was the issue for mine. I think it was the combo of bottom 3/4" inch of small ceramics combined with grit that was the issue. Also, there was almost no grit breakdown after 7 days but with the exact same load of rocks, ceramics, grit and water just loaded differently I had almost full grit breakdown after 5 days. Next barrel load or empty I can take a pic but do make sure to mix sizes with probably 1/3 being small ceramics( to round edges) and/or small gravel size rocks. Then other 2/3 in mix of size with a couple, at most, being bigger than 1-1.5 inches. Havent messed much with slurry thickeners aside from adding a tblspoon or two of used grit. But none used when had issue. Slurry is on the thinner side normally but when this issue occured it was basically dirty water. When opened barrel I could see what rocks were what as no slurry sticking to or covering the rocks. Grit usage is going off what I've read numerous places. But this is not the difference between too much grit or inefficient breakdown. This is virtually no grit breakdown, rocks felt uniformly rough all over. They were practically smooth before batch started. And actually, after 5 days rerun they were done and part of first load I did in lot o. When I have a free barrel I am going to experiment and attempt to recreate the issue by loading barrel as I did before. If I am able to recreate the problem then, at least for me, I will have my answer.
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gnuuser
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Post by gnuuser on Aug 4, 2019 16:39:22 GMT -5
Oldschoolrocker,
What you're describing is exactly what happened to me this time. I loaded everything properly (or so I thought), put water in, put in my usual amount of grit (which usually works perfectly), ran it, didn't touch it all week, but at the end of the week I ended up with dirty water and a cement of unused grit and small stuff at the bottom of the barrel. Other times it has happened, I'm certain that I washed the grit to the bottom. So, I think I'm going to try your method of loading big rocks first, then medium, then small, then water, then grit.
There have been some times where I did have a nice slurry going, but ended up with a cement of sludge (compacted slurry with very little grit) and ceramics. In those cases, it obviously was working for several days, so I must have stood it up after the slurry formed. It must be that settling after loading is possible, as well.
What confuses the heck out of me is why some people never experience this after years of tumbling, regardless of loading procedures, and some people (like me) seem to have this problem fairly frequently, even while being as careful about it as possible.
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oldschoolrocker
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Post by oldschoolrocker on Aug 4, 2019 16:56:06 GMT -5
Oldschoolrocker,
What you're describing is exactly what happened to me this time. I loaded everything properly (or so I thought), put water in, put in my usual amount of grit (which usually works perfectly), ran it, didn't touch it all week, but at the end of the week I ended up with dirty water and a cement of unused grit and small stuff at the bottom of the barrel. Other times it has happened, I'm certain that I washed the grit to the bottom. So, I think I'm going to try your method of loading big rocks first, then medium, then small, then water, then grit.
There have been some times where I did have a nice slurry going, but ended up with a cement of sludge (compacted slurry with very little grit) and ceramics. In those cases, it obviously was working for several days, so I must have stood it up after the slurry formed. It must be that settling after loading is possible, as well.
What confuses the heck out of me is why some people never experience this after years of tumbling, regardless of loading procedures, and some people (like me) seem to have this problem fairly frequently, even while being as careful about it as possible.
Hopefully it will help. And I agree that compacted slurry and smalls and maybe some unused grit at bottom is from settling when barrel is upright. I just dont see how grit could go whole week and not have SOME grit breakdown. I definitely dont have the knowledge many on here have so only going off my own experiences. Hopefully, regardless of why, we dont run into this issue too often as there is little that's more frustrating to me than finding I wasted a whole week basically washing the rocks
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gatorflash1
spending too much on rocks
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Post by gatorflash1 on Aug 4, 2019 21:49:04 GMT -5
I probably have a bunch of dumb questions here but I'll ask you anyway. Are you using the proper amount of grit, or are you overloading it? That would be an easy problem to solve. Are you using tumbling media like ceramics to keep the brew stirred up? That would be another easy problem to solve? Are you using any sugar, etc. with your batch that might cause this? You might try adding a spoon of Ivory soap flakes. Are you waiting long enough to give the grit time to do it's work? Easy problem to fix. GatorFlash1,
I use 2 tablespoons of grit per pound of rocks. Sometimes I use ceramic media, if I don't have enough small stuff to put in. I don't use anything but grit and water except when washing rocks/barrels in preparation for polishing.
9 out of 10 tries, everything turns out just fine, but 1 out of 10 tries, I unexpectedly get this cement-on-the-bottom of the barrel thing.
It must be what CaptBob says. He's right... it never happens at the lid end, so I MUST be standing them up at some point and not realizing it. The only other thing I've found is that it happens if I put grit in first, and wash it down with water. It causes the cement thing every time. It's the times like this when I do all the right things and it happens anyway that I can't figure out!
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