zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Jan 17, 2014 19:31:35 GMT -5
The instructions that come with the Lot-O-Tumbler start with 180/220 grit. Other recipes I've seen on this forum start with 120/220. Nobody mentions 60/90. I'm doing a batch of earrings that I preform, drill, & bevel & thought that I'd need something more aggressive than 220 to smooth out my bevels, so I put in 1 Tablespoon of 60/90. I didn't see any grit sticking to the rocks after 18 hours, so I carefully emptied out the barrel & saw that it had clumped to one edge of the bowl & wasn't distributing itself onto the rocks. Is this the reason why nobody recommends 60/90? BTW, I put the grit in & then remembered the soap & Borax, which I then added. Lynn
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Mattatya
spending too much on rocks
Member since June 2012
Posts: 452
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Post by Mattatya on Jan 17, 2014 19:42:20 GMT -5
Vibe tumblers are more aggressive then rotory's. 220 works great but best when pre formed.
I get my rocks in shape by pre forming or tumbling first in a rotary using 60/90 then do my other steps 220 and onward in a vibe.
I don't use Borax or Dawn until your done with each step. I add a couple drops or teaspoon in the slurry to clean grit off the stone. Rinse then fill vibe up with water and add it again to clean barrel.
Then I use a separate barrel just for polish and burnish.
I use the same method for tumbler barrels as well.
There is a good vibe tumbling recipe's on RTH including Krystee TnTmom vibe recipe on obsidian vibe tumbling.
Cheers, Matt
Sent from my SPH-D710 using proboards
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Post by pauls on Jan 17, 2014 22:32:10 GMT -5
I think you have figured for yourself why coarser grits aren't used much, they tend to clump in the bottom. I use 45 grit as my first grit for a really aggressive grind by adding some muddy slurry from a previous batch, it just helps keep it in suspension.
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unclesoska
freely admits to licking rocks
All those jade boulders tossed in search of gold!
Member since February 2011
Posts: 934
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Post by unclesoska on Jan 17, 2014 22:46:37 GMT -5
The 1st and last time I used 60/90 in a vibe tumbler, the bowl had become translucent in that you could now see light thru it. Needless to say, I wound up scrapping the bowl.
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zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Jan 17, 2014 23:04:07 GMT -5
Thanks for the responses. It looks like I will dump out the 60/90 & put in 220 instead. Lynn
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Geoff
spending too much on rocks
Please add 1074 to my post number.
Member since December 2012
Posts: 446
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Post by Geoff on Jan 18, 2014 0:11:14 GMT -5
Not so fast! The lot o handles 60/90 fine as long as you filled the dimple in. I used flowable silicone to fill it in flush with bottom and let it cure for several days. You'll need to keep a closer eye on mud consistency, but I've used 60/90 in my single and double lot o with success.
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Post by connrock on Jan 18, 2014 11:16:20 GMT -5
I've had Lot-O's for over 20 years and rarely use anything more coarse then 120/220. Unless pre-forms have deep chips from drilling and or have deep areas around the edges from rough grinding them,I think 120/220 would do fine for "de-burring" the pre-forms. I KNOW it will work if the drilled holes and the edges of your pre-forms were first smoothed down with a 220 grinding wheel. One reason 60/90 isn't used in a Lot-O is because it can cause premature wearing of the barrels.As you found,it lays either right on the bottom or to one side which causes the grit to wear the barrels out. Another point is that when you use 60/90 grit you have to tend to the unit MUCH more often as the rocks grind down very fast and you get a very thick muddy slurry that brings the rolling action to a halt! If this does happen you can spray water into the barrel and take a tablespoon to mix up the rocks/mud at the bottom of the barrel to get the rolling action back enough to ease the cleaning process. connrock
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zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Jan 18, 2014 13:37:50 GMT -5
I emptied out the barrel agian & saw that the grit (& ceramic pellets) were clumped up to one side of the bottom, but not in the bottom itself. I had previously filled the empty space at the bottom with silicone as suggested. Now it's got 220 in it. Let's see how it does. Lynn
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zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Jan 18, 2014 19:07:01 GMT -5
OK, so I cleaned out the barrel & sifted the preforms & pellets from the 60/90 grit. I added back the preforms & ceramic pellets. The barrel is about 3/4 full. 2/3 of that is preforms & 1/3 is pellets. While the tumbler was on I then slowly added 1/2 teaspoon of soap flakes & 1 teaspoon of Borax. Then I slowly added 1 Tablespoon of 220 grit. I let it run for several hours, checking it occasionally. I never saw the gray coating I was used to seeing in the past. I emptied it out & saw that the grit, some pellets & some preforms were clumped up near the bottom.
I've tumbled earring preforms before & didn't have the clumping problem. What am I doing wrong? Carborundum is carborundum & should weight the same from batch to batch, right? So why is it sinking & clumping? Lynn
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Post by pauls on Jan 18, 2014 20:22:47 GMT -5
How much water did you add?
I tend to just put the damp rocks in and then the grit, watch it for a while and just a few squirts of water from a spray bottle until the action is right, its a very fine line between just enough and too much.
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Post by johnjsgems on Jan 18, 2014 20:41:00 GMT -5
Too much water will cause grit to settle to bottom and wear through the bowl. Best reason to not use 60/90 is vibes in general don't alter shapes so no reason for coarse grit. Most brands of bowls are affected by coarse grit. Can't speak about Lotto as I've never used one. With that many flat stones I would use more like 70% ceramics by volume.
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Post by connrock on Jan 19, 2014 7:32:51 GMT -5
Sometimes when starting a load and adding powdered soap the soap and borax doesn't fully dissolve for a while. By adding the grit right away may be giving you a false indication of how much water to use. Try letting the soap/borax dissolve for a few minutes before adding the grit and spray water in as needed. Also,the barrel should be full and not just 3/4 full and as John mentioned,,,more ceramic media and less rocks. connrock
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zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Jan 19, 2014 12:44:18 GMT -5
John said too much water will cause the grit to clump. After rinsing the rocks, I poured all of the water out before adding the soap, Borax, & grit. I didn't add any more water. Right now I've dumped everything out to let it dry before I try again. I added just 1 Tablespoon of 220, not the 2 Tablespoons recommended. I would think adding more grit rather than less would tend to make it clump more. Am I wrong there? Lynn
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Post by johnjsgems on Jan 19, 2014 15:56:11 GMT -5
Can't say for Lotto but with the 10 lb. Gy-Roc it is only one tablespoon.
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Post by connrock on Jan 20, 2014 8:33:50 GMT -5
The thing about the "clump" being to one side is puzzling.The only thing I can think of is that the counter balances are not lined up to each other which would cause an erratic action and "maybe" force the grit to one side of the barrel?
Are you sure that the 2 counter balances are lined up on the motor fans?
With the way you're loading the barrel,,,to me,,,there HAS to be something mechanically wrong for all of this to happen.
Let me ask you this,,,,when the rocks go around in the barrel,,,are they "rolling" from front to back or are the rolling to one side?
Also,,,,is the barrel full?
It's hard to diagnose without seeing and hearing what's going on.
After you add the grit,,,do the rocks have a wet shiny look or are they dry looking? Are the rocks rolling freely or are they stuck to each other?
connrock
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Post by johnjsgems on Jan 20, 2014 10:19:10 GMT -5
Without enough ceramics the flat rocks could very likely rotate in a mass stuck together.
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zarguy
fully equipped rock polisher
Cedar City, Utah - rockhound heaven!
Member since December 2005
Posts: 1,791
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Post by zarguy on Jan 29, 2014 1:34:26 GMT -5
OK, I re-added the rocks, ceramic media, & grit. This time I did not add Borax or soap flakes. Now everything is as it should be. The rocks & pellets are coated with gray, not clean like before. I guess I should only use Borax & soap for the pre & polish stages, right? Lynn
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Mattatya
spending too much on rocks
Member since June 2012
Posts: 452
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Post by Mattatya on Jan 29, 2014 2:06:30 GMT -5
Sounds like you got in going back in good shape. I use Dawn after each grit run. I leave the grit in and add a couple drops of Dawn in then fill I barrel with water. I let it vibe for a bit (under 1/2 hour). Seems to help me with moving leftover grit and slurry off the stones, making them easier to clean up the rocks when rinsing.
After my polish cycle is done. I repeat process with dawn, and water. Then rinse well and do a burnish run of stones, water spray, Borax or ivory soap for about an hour to burnish them.
I live in Washington next to the water. The temperature changes and moisture in the air make it a pain for me to keep my water/grit balance just right.
I usually don't even spray water into the barrel after adding grit. I just rinse the stones and use their wetness to get started.
I fill the barrel with stones and fill with water all the way to the top. Then tip upside-down and drain the water until no droplets come out of the barrel. Then start it up and add grit very slowly till rocks are covered and milky grey looking. I have to watch it constantly though cause water builds up in there or dries out from air moisture. I'm using my lot-o outside covered on the deck.
Look forward to seeing your progress. Matt
Sent from my SPH-D710 using proboards
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