ChicagoDave
has rocks in the head
Member since June 2016
Posts: 720
|
Post by ChicagoDave on Aug 30, 2016 17:54:59 GMT -5
Decided to check my obsidian after a couple of days tumbling. Opened the barrel up. Went to grab a few stones and only found a handful floating around. The rest were plastered to the bottom. It took about 20 minutes to pry each of them out and get them rinsed off. How in the world does a tumbling barrel get a solid layer of grit and stone on the bottom??!! There was all kinds of water floating on the top. I'm very confused as to how this could even possibly happen. I only had my barrel about 60% full and had water to the bottom of the top rocks. 10TB of 60/90. I didn't think to take a picture until I was almost done excavating. Any help would be appreciated? After getting everything cleaned up I tossed in some small ceramic media to bring the barrel to about 75%. Added 8 TB of 60/90 and water almost to the top of the media. Rolling again!
|
|
|
Post by spiceman on Aug 30, 2016 20:53:09 GMT -5
I know this is no help, But your not alone. I had the same problem. I added some borax but haven't checked it out yet. Well, I know one thing, my tumble stones made the concrete because they are gone. Dale
|
|
ChicagoDave
has rocks in the head
Member since June 2016
Posts: 720
|
Post by ChicagoDave on Aug 30, 2016 21:40:16 GMT -5
I was actually shocked how smooth the obsidian was. When the pieces went in on Saturday they were all rough and "broken glass" like, but there was still plenty left. So maybe this happens when things break down quickly. Is the answer less grit for something like this? Or will the extra ceramic media keep things moving along?
|
|
|
Post by pauls on Aug 30, 2016 21:49:08 GMT -5
What size is that barrel?
10TB is 10 tablespoons, not teaspoons, is that right? Whats that about a pound of grit?
10 Table spoons seems and looks like way too much grit. You need enough grit to start getting a slurry going, or do as jamesp does and add clay to make a slurry. I would be cleaning it out, save your grit its perfectly OK and start with 2TB for example. just enough to lightly coat your rocks, when your slurry gets going after a week put a bit more in.
|
|
ChicagoDave
has rocks in the head
Member since June 2016
Posts: 720
|
Post by ChicagoDave on Aug 30, 2016 22:00:01 GMT -5
This is a 6lb Lortone barrel. And yes, that is 10 tablespoons of grit. Just following what the directions told me to do. Also saw this amount mentioned on the stickied post at the top of this message board. I don't think this is close to a pound of grit. I have cleaned and reloaded the other barrel about 8 or 9 times using the same 5 pound bag and there is still a few more changes worth. I think alot of the "grit" you're seeing is ground down obsidian.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Aug 31, 2016 4:51:36 GMT -5
Obsidian grinds fast in the coarse stage. And the slurry builds up fast. Then it makes thick 'mud'. The mud from obsidian and glass is quick to concrete if you stop rolling. If you remove the barrel and set it down the mud can coagulate in minutes. Or turn the tumbler off and leave it sitting on the shafts. It looks like you are grinding the obsidian quickly and making a lot of mud which is great. one cup is 47 teaspoons-for 6 pounds of rock I would run 1/3 cup or 12 teaspoons. one cup is 16 tablespoons, I personally would never run 10 tablespoons, but 10 teaspoons for 6 pounds. Looks like you are running 3 times too much grit. The bottom of your barrel looks like too much grit. Not so much obsidian mud as it is very fine like cream. Did you directions say 10 teaspoons or 10 tablespoons ? I would go buy a 1/3 cup measuring cup and use it for your measure. I have been using 1 cup for 16-20 pounds of rock for a long time, many tumbles. A lot of times people have asked why can't they use more grit. Concretion problem is the reason. pauls nailed the problem. PS Beware of abbreviations TB tbsp tsp etc, they tend to be confusing. You can buy a 1/4 1/3 1/2 cup measure and throw away all those spoons. Try 1/3 cup(.33 cups) instead of 10/16 cup(.63 cups). Makes a big difference.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Aug 31, 2016 5:06:45 GMT -5
Your grit is much heavier than obsidian mud, so it is quick to settle and concrete. But obsidian mud is quick to concrete too for some reason. Good luck Dave.
|
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Aug 31, 2016 7:40:38 GMT -5
Wow. No doubt, tablespoons. Another point, obsidian is soft. So soft that coarse grit breaks down slower because it is soft. I would still cut back to 5 tablespoons and give it a go. You can dump the contents in a pan and wash. Let settle for a minute and pour off the water. Coarse grit particles can be seen in the bottom of the pan. If the coarse grit has not broken down.
Anyway Can't hurt anything. Concreted stones can get damaged or heavily frosted in the case of obsidian. Lopsided wear, since they are held in place. Don't like concretions.
Amazed at the dosing rate.
And I would only use 1/6 of a cup of fine and polish. They have polish down at 11-12 tablespoons. That seems off too.
|
|
ChicagoDave
has rocks in the head
Member since June 2016
Posts: 720
|
Post by ChicagoDave on Aug 31, 2016 7:51:36 GMT -5
The Lortone directions also say rough tumble will be done in about 7 days! So I guess I need to stop paying attention.
I've been thinking about my process and realize why this might have happened. I usually run my barrels for the full 7 days. Never check on them. I pull them off the tumbler and then get everything setup. Pull the lid and get it cleaned. Then dump everything and start cleaning. I'm guessing after 7 days the grit has broken down and doesn't settle so quickly. This barrel had only run for a few days and the grit was still "heavy". It explains quite a bit - thanks for pointing me in that direction. I was very confused how a rolling barrel could push all the grit and rocks to one side.
|
|
|
Post by Garage Rocker on Aug 31, 2016 7:58:42 GMT -5
ChicagoDave , I don't think you're off base with the two tablespoon/pound of rock formula. There are many on here that use that approximate ratio. Everyone who has tumbled has had something like that happen to a barrel. I attributed it to too much water and the grit never circulating to form a slurry, but who really knows. The cat litter trick has cut out any such issue for me. My 3 lb. barrels were always trickier to get a good slurry than the larger diameter 12 lb. barrel. As jamesp said, perhaps cut back on the grit a little for something soft, like obsidian. It sucks to waste time on a bad tumble, but it comes with the territory.
ETA: Start listening closely to your barrel as it rolls. You should be able to hear what's going on in there. As the slurry thickens, the thump and crash of rock should quieten. If it goes too quiet, you may have made concrete again and your rocks are stuck to the side. It's all more of an art than exact science, that's what makes it maddening sometimes. That and the fact that there is more than one way to do it. You'll find what works best for you.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Aug 31, 2016 11:27:08 GMT -5
ChicagoDave , I don't think you're off base with the two tablespoon/pound of rock formula. There are many on here that use that approximate ratio. Everyone who has tumbled has had something like that happen to a barrel. I attributed it to too much water and the grit never circulating to form a slurry, but who really knows. The cat litter trick has cut out any such issue for me. My 3 lb. barrels were always trickier to get a good slurry than the larger diameter 12 lb. barrel. As jamesp said, perhaps cut back on the grit a little for something soft, like obsidian. It sucks to waste time on a bad tumble, but it comes with the territory.
ETA: Start listening closely to your barrel as it rolls. You should be able to hear what's going on in there. As the slurry thickens, the thump and crash of rock should quieten. If it goes too quiet, you may have made concrete again and your rocks are stuck to the side. It's all more of an art than exact science, that's what makes it maddening sometimes. That and the fact that there is more than one way to do it. You'll find what works best for you. You are correct Garage, I do go light on grit. Never noticed. Probably make up for it in coarse since I add grit every 2-3 days and don't do many clean outs. Use a lot of SiC 30 w/the 2 step.
|
|
metalsmith
Cave Dweller
Member since October 2012
Posts: 1,537
|
Post by metalsmith on Aug 31, 2016 12:46:59 GMT -5
I'll venture rheopexy (/rheopecty) due to the very fine product that you obtain from grinding glass and the particles acting as colloids.
|
|
Deleted
Deleted Member
Member since January 1970
Posts: 0
|
Post by Deleted on Sept 1, 2016 1:02:19 GMT -5
How long did the barrel sit to allow the stuff to settle on the bottom and make the concrete mass?
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Sept 1, 2016 5:06:24 GMT -5
@shotgunner
About the only way I could coarse tumble glass or obsidian with 30 grit was to do a 'separation clean out' about every 3-4 days. It only took 2 minutes or less after stopping if that to get a concretion after day 3-4.
separation clean out
1 dump contents into (white)pan. 2 run hose in pan full flow and make glass mud over flow, unused grit is heavy and settles to bottom. 3 return contents including unused grit in bottom of pan into tumbler.
I used the same separation clean out to make sure grit particles were all gone after the last SiC 30 breakdown run lasting 10-14 days. Sic 30 was gone. SiC easy to see even if finely ground, shows up as black sand in bottom of white pan. sg SiC 3.1 sg glass 2.5 sg quartz 2.6
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Sept 1, 2016 5:28:21 GMT -5
The Lortone directions also say rough tumble will be done in about 7 days! So I guess I need to stop paying attention. I've been thinking about my process and realize why this might have happened. I usually run my barrels for the full 7 days. Never check on them. I pull them off the tumbler and then get everything setup. Pull the lid and get it cleaned. Then dump everything and start cleaning. I'm guessing after 7 days the grit has broken down and doesn't settle so quickly. This barrel had only run for a few days and the grit was still "heavy". It explains quite a bit - thanks for pointing me in that direction. I was very confused how a rolling barrel could push all the grit and rocks to one side. 7 days not. I usually run agate and other hard rocks 1-3 months and add coarse grit 8-15 times or more. Not sure why they would say 7 days. Seen that subject come up before. That is an LOL. Would be nice if that were true. Barrels can get accumulation on the end running stuff like glass and obsidian. Especially if you have a lot of thin chips. Obsidian is a tough tumble to start out with. Just letting you know. Especially when it comes time to get a polish. Obsidian is soft at ~Mohs 5, agates are hard at Mohs 7. Mohs 7 rocks much easier to tumble to a polish.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,169
|
Post by jamesp on Sept 1, 2016 6:46:43 GMT -5
I'll venture rheopexy (/rheopecty) due to the very fine product that you obtain from grinding glass and the particles acting as colloids. Colloids a good possibility. Here in Georgia our felspar based clay is very colloidal. Dams for lakes are made by adding layers of clay and then running over each layer with a bulldozer. That arranges the colloidal plates flat layer after layer. Makes for the ultimate water seal. Dam leaks are usually below the packed clay dam where it sits on rock or soil mixed with organics. The colloids also get lifted and washed into rivers water making our rivers muddy. Depositing on the bottom of slower flowing sections of the river making thick silt deposits. A sort of pollution.
|
|
ChicagoDave
has rocks in the head
Member since June 2016
Posts: 720
|
Post by ChicagoDave on Sept 1, 2016 7:02:48 GMT -5
@shotgunner, I would say the barrel was sitting for less than 5 minutes.
|
|
metalsmith
Cave Dweller
Member since October 2012
Posts: 1,537
|
Post by metalsmith on Sept 1, 2016 11:26:51 GMT -5
I'll venture rheopexy (/rheopecty) due to the very fine product that you obtain from grinding glass and the particles acting as colloids. Colloids a good possibility. Here in Georgia our felspar based clay is very colloidal. Dams for lakes are made by adding layers of clay and then running over each layer with a bulldozer. That arranges the colloidal plates flat layer after layer. Makes for the ultimate water seal. Dam leaks are usually below the packed clay dam where it sits on rock or soil mixed with organics. The colloids also get lifted and washed into rivers water making our rivers muddy. Depositing on the bottom of slower flowing sections of the river making thick silt deposits. A sort of pollution. Yeah, the reason clays stick together is the electro-chemical bonds that form; probably formed while it was spinning and maybe the motion induced by the spinning would assist with the generation of electric charges between particles.
|
|
Deleted
Deleted Member
Member since January 1970
Posts: 0
|
Post by Deleted on Sept 1, 2016 11:59:33 GMT -5
@shotgunner, I would say the barrel was sitting for less than 5 minutes. Wow! That amazes me. Also that jamesp confirns and has solved the issue... Wow
|
|