nickspapaw
off to a rocking start
Member since October 2012
Posts: 4
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Post by nickspapaw on Jan 12, 2013 9:21:54 GMT -5
OK, I'm a newbe on here. I was able to get my grandson a bunch of tumbling stuff for Christmas and we are having a blast with it. But, we have a problem. We are running a vib tumbler and had made it to the polish stage. We are using a Diamond Pacific MT-10 tumbler. Using the large barrel, we went through rough-pre polish. We then moved to the 4# barrel for polish only. Here is where we goofed up. The rocks had a pretty nice shine to them after pre polish, but after 5 days in polish they were junk. I suspect that we hammered them into submission. My question is what went wrong. I have 3 theories about our mistake. 1. We had varying size rocks in the barrel which caused them to beat each other up. 2. Due to the different rock size, we had the vibration turned up too much. 3. We just don't know what the heck we are doing. ha ha In spite of this, we are having a blast and also we are doing a clean out on our Lortone QT-66 today. We are running a single barrel on that one, saving the other barrel for polish stage. Any and all help is appreciated. Thanks
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Post by Jugglerguy on Jan 12, 2013 10:13:12 GMT -5
I do all of my rough tumbling in my Lortone rotary tumblers and then all the other stages in my Lot-O vibratory tumbler. I have not used my rotary tumbler for anything but the 60/90 stage. I don't have any experience with the vibe you're using, so I don't know about adjusting the vibration. My Lot-O has the vibration set at the factory and is not meant to be adjusted unless there's a problem
Different size stones are not your problem. You want to have different sizes. If you just had big rocks, they would only touch each other in a few spots, so the grit would not be as effective. By including smaller rocks, they get coated with grit and get in between the larger rocks to help polish them.
Are you using ceramic media? I just looked up your MT-10 on The Rock Shed website. It said this in the description:
The ceramic media works like the small rocks to carry grit, but also cushions the rock to make it a little more gentle.
You haven't said what kind of rock you're tumbling. It's best not to mix rocks of different hardnesses. Could you post pictures of your rocks?
You could have contamination of grit from one stage to the next. Did you get all of the pits and cracks ground out in the first stage? I sometimes run my rocks for weeks or months in the first stage before I go on. I remove only the perfect rocks in weekly clean outs during stage one and replace them with more rough rock. If you have holes in your rocks, rough grit can get carried to later stages where it falls out and ruins that stage. After the first stage, everything else goes into the vibe and doesn't take long. The first stage takes forever. If you just started at Christmas, my guess is that you rushed the first step.
Rob
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nickspapaw
off to a rocking start
Member since October 2012
Posts: 4
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Post by nickspapaw on Jan 12, 2013 10:23:56 GMT -5
I didn't use any media. I also have a mix of hardness involved also. Since I went to a smaller barrel for polish, I still have rocks that haven't been through polish. I will try to throw up a pic of them if I can figure out how to attach on here.
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Post by Jugglerguy on Jan 12, 2013 10:40:51 GMT -5
When you mix hardness, the soft rocks suffer. As you polish the rest, you might want to separate by hardness if you can.
You can upload pictures right from here, but you can only post one per message. Most people use a photo hosting site and link from there. I use flickr, but I'm not sure my method of getting pictures onto this site is the proper method. I'll let someone else explain that to you!
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herchenx
Cave Dweller
Member since January 2012
Posts: 3,360
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Post by herchenx on Jan 12, 2013 12:05:51 GMT -5
Pics would definitely be helpful in diagnosing, but jugglerguy is steering you right. Before anything goes in the vibe you usually want to do a rough run (a lot of rough runs) in a rotary or use a grinder or wheel to smooth out the exterior of the stones so they don't have any cracks or pits.
I've had somewhat nice stones go to crap in the polish stage because either they were slightly porous or cracked and the very fine white polish penetrated into the cracks and made the stones look frosted with white, and not at all shiny.
I would suspect media as an issue in this case because the lack of contact points that ceramic provides would allow the stones to rattle together a lot and damage the finish, pics might help diagnose which of those or another issue is to blame.
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jspencer
freely admits to licking rocks
Member since March 2011
Posts: 929
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Post by jspencer on Jan 12, 2013 23:18:35 GMT -5
The more variation in your size of rocks the better just as described for surface contact. I would guess a mix of hardness as the culprit. Possibly cross conatmination if you had any deep pits not rinsed completely before moving on. I run mine as dry as possible in the vibe adding water by a spray bottle each time I change grit. If you have them loaded to full bowl and water content is right you will see the rocks moving around the bowl as well as moving top to bottom in a cyclone action. Don`t be afraid to leave them in polish for 4-5 days either. I know 2 days is popular practice but I sort of think it helps to break down the polish more. Too much water in bowl results in grit sitting in bottom of bowl. You shouldn`t be able to see the rocks colors easily once they run awhile when you have a good mix. I also always add Borax to mine along with grit or polish.
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