pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 28, 2018 23:07:11 GMT -5
It was a nice day to cut & grind........all tumblers available and I had nothing scheduled and no distractions.
Set-up and started into the sorted Lavic I had set-aside just for this occasion......:
Humble and basic approach
Started with approx. 7lbs of rough, various types, nothing bigger than my fist...(I have average size hands)..:
Some of the selection
Cut and saw shaped, took my time and even switched to a more aggressive blade to help speed up the disc shaping.....it worked well...:
About 2/3rds of the set-aside batch
Moved onto the diamond disc.......got about 2-3lb barrels completed...:
Wet and ready for tumble
Everything shown is from Lavic Siding........even the Quartz type Chalcedony I dug up near an Iron Wood bush.
Closer view of wet
I was considering throwing them into the vibe with 120/220 Sic since they shaped so well, fairly easy material to work with. Just a bit messy.........but I'll give them a weeks rotary spin in 60/90 and some ceramic cushion first........ never can tell, I've had both success and failures going either option.......So I'll go with my gut on these.......it's my first time tumbling Lavic...!
|
|
quartz
Cave Dweller
breakin' rocks in the hot sun
Member since February 2010
Posts: 3,352
|
Post by quartz on May 28, 2018 23:54:24 GMT -5
It seems to me that running ceramic with a 60/90 run is counterproductive, you want max. grind and let the next run smooth them out, rather than spending time grinding on the ceramic.
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 29, 2018 6:46:35 GMT -5
It seems to me that running ceramic with a 60/90 run is counterproductive, you want max. grind and let the next run smooth them out, rather than spending time grinding on the ceramic. Point taken.......However, the ceramic in question has abrasives and is angular. I do not intend to "round" these stones out, rather using the ceramics as a cushion to help prevent bruising, chipping and fractures/scaring during the 60/90 rotary cycle.......I found the material to be softer than anticipated while cutting/grinding, not an agate hard, brittle/dense, more on the order of a Zebra Jasper, which I am familiar with.......thus, the shorter rotary cycle is intended to "sand" the material for preparation of vibe 120/220 and further vibe polishing. Have had very good results with this approach on other Jasper of similar quality........besides, I don't have any other filler material available I trust. The cutting did not render much "waste".
As stated previously, this is my first attempt for Lavic.......I've got over 40lbs left, just need to reduce some of it to smaller 7" saw blade capacity.........we'll see, thanks for the observation.
|
|
|
Post by rockpickerforever on May 29, 2018 8:13:08 GMT -5
You've got a good start on them, Joe pizzano . Glad you were finally about able to squeeze some rockin' time into your busy schedule. I know that feeling! Those are going to make some great tumbles. Now do you see what I meant about material from Lavic being messy? Not just the reds, but the yellows, too. Will be interesting to see how your choice of media works out. Good luck with them. Jean
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 29, 2018 12:45:51 GMT -5
Thanks Jean.......yes the material is messy, when powdered into the mud wash it feels almost oily and it stains, my hands have an orange glow to them.......lol...I'll bet this stuff has been used as a pigment for paint, it's that penetrating.
I managed to round up some (chips from collection and this mornings hammer/chisel session), going to let the tumbles ride as is with abrasive ceramic, after a week I'll open up the barrels and inspect. Will add, as needed, those chips......unless they appear ready for vibe. Guessing, based on your experience with this material, I'll be running rotary for more than a week...........hope, due to my prep shaping, undercutting is at a minimum.
I've got another dual rotary open, may just cut some more and only saw shape, use the chips in that batch......make the comparisons as they progress........once they get into the vibes, I'll know what I'm dealing with.
Looking forward to your Lavic batches........!
|
|
NRG
fully equipped rock polisher
Member since February 2018
Posts: 1,687
|
Post by NRG on May 29, 2018 14:58:49 GMT -5
Cant wait to see the finish.
You cant bruise lavic in a rotary 80% full.
|
|
nchillbilly
starting to spend too much on rocks
Member since January 2018
Posts: 212
|
Post by nchillbilly on May 29, 2018 16:54:40 GMT -5
Good afternoon Joe. Those look like they should make some awesome looking tumbles. Can't wait to see how they turn out.
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 29, 2018 17:55:25 GMT -5
Cant wait to see the finish. You cant bruise lavic in a rotary 80% full. Thanks Scott.......good to know. I'm glad I've got at least two Lavic specialist here to lean on...!
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 29, 2018 18:04:43 GMT -5
Good afternoon Joe. Those look like they should make some awesome looking tumbles. Can't wait to see how they turn out. Thanks J.T.
I'm hoping so........I'm trying the same method I performed on a couple of batches RS Zebra Jasper that turned out very nice......it's the only thing close to the Lavic I can base my experience on. Seems like every new material ventured turns out to be a trial until a few batches have been completed......guess that's the name of the game and part of the mystery that keeps us coming back for more......lol
|
|
|
Post by aDave on May 29, 2018 19:34:32 GMT -5
I was considering throwing them into the vibe with 120/220 Sic since they shaped so well, fairly easy material to work with. Just a bit messy.........but I'll give them a weeks rotary spin in 60/90 and some ceramic cushion first........ never can tell, I've had both success and failures going either option.......So I'll go with my gut on these.......it's my first time tumbling Lavic...! It would have been interesting to see what your preshaped stuff would have done going straight to 120/220 in the vibe. I think you'll find that your original perception is correct, in that this stuff will shape fairly quickly for you. I don't preshape my Lavic, and it doesn't take too long to shape very nicely - certainly not like alot of other hard stuff. Unfortunately, I can't give you a timeline, as I'm always running mixed batches, and I don't log when I top off with different material. If nothing more than for the varieties that turn out, this is one of my favorite materials to tumble. At the same time, however, it can be a bit frustrating. It tends to pit pretty often and sometimes you end up with pockets or crevasses; just when I think I might be able to remove a flaw or two, another forms. It's just the nature of this beast. The more you roll it, you'll get a feel for having maximized your return and you've gotten the best out of the rock that you can get. Sometimes that means moving the stuff along even though it may have some flaws. Good luck, and have fun with it.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,563
|
Post by jamesp on May 30, 2018 5:01:50 GMT -5
Cant wait to see the finish. You cant bruise lavic in a rotary 80% full. This is fact. Ceramic will retard coarse grind and shrink your ceramics quickly. I tumble thin glass in 85% barrel fill at whooping 80 RPM with zero breakage and frosting. Can't beat fuller barrel for protecting your babies.
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 30, 2018 12:13:12 GMT -5
For conversational purposes only (it's not a debate), I'm gonna throw a little shade on the "ceramic" concerns...:
"It seems to me that running ceramic with a 60/90 run is counterproductive" "This is fact. Ceramic will retard coarse grind and shrink your ceramics quickly"
Ceramic Angle #2....Abrasive - 1/4" x 5/8"
Since my original concerns and course of action with the Lavic material were to....: 1........ Not to loose to much size/volume, bruising, undercutting and or add fractures (common concerns) with rotary tumbling experienced in the past. 2........ Add volume to the load (+80% capacity) to effectively increase action, separate pieces from sticking or banging together. 3........ Effectively distribute media through out the load, while also increasing the "sanding/grinding" action....thus abrasive filler. 4........ Shortened rotary cycle to only eliminate the prep shaping and sanding scars in order to "concentrate" further efforts with vibe applications.
Since I had spent the time and effort disc shaping to help prevent the above concerns and speed-up the process, not having had previous experience with this type of Jasper, noticing, while cutting/shaping, that this material was not as dense as other Jasper I have worked with and having had very good results with the same process with Jaspers that seem to be of similar quality..................and, being under the impression (based on previous personal experience and advice from others more knowledgeable), ceramics, particularly the type being used in this process, could very well satisfy my expectations..............withstanding the concerns of ceramic wear and or grinding retardation.
After all, isn't ceramic media intended for the purposes stated above....?
It is my plan to continue with the use of ceramics throughout the entire process.....those without abrasives once loaded into the vibes..........no mixing of other materials, just Lavic Jasper.....!
I also want to acknowledge this fact......I REALLY DO APPRECIATE all of the input I receive from everyone who provides insight and takes the time to view my novice approaches to "speeding" up the process while in search of the that "magic" formula to "perfection"........Thank you one and all....!
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,563
|
Post by jamesp on May 30, 2018 12:59:01 GMT -5
Ceramic is more used as media in 500-1000-5000-14,000(i.e. finishing). Impractical during coarse grind. Unless you get ceramic media that is designed for cutting. Ceramic media comes in many abrasive levels.(depends on particle size at firing) Some is aggressive and eat thru the toughest vibe hoppers.(see Kramer Industries) Rock Shed sells a polishing ceramic media. Best used for finishing stages.
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on May 30, 2018 19:53:15 GMT -5
"Ceramic is more used as media in 500-1000-5000-14,000(i.e. finishing). Impractical during coarse grind........ Unless you get ceramic media that is designed for cutting."
Yes, conventional wisdom would agree with that......unless of course, like observed, abrasives are added.......like the Covington media I'm using........specifically for the use with 60/90 and 120/220 stages.......not recommended for anything higher grade.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,563
|
Post by jamesp on Jun 1, 2018 18:07:35 GMT -5
"Ceramic is more used as media in 500-1000-5000-14,000(i.e. finishing). Impractical during coarse grind........ Unless you get ceramic media that is designed for cutting."
Yes, conventional wisdom would agree with that......unless of course, like observed, abrasives are added.......like the Covington media I'm using........specifically for the use with 60/90 and 120/220 stages.......not recommended for anything higher grade.
I wish you well with the ceramics. I never have tried ceramics of any sort in coarse grind for reasons previously stated. I assumed they would grind against each other and wear out quickly and wear down a portion of added abrasives. Have you considered slurry thickener ? I am a clay slurry user similar to Covington's product for the following reasons: It is cheap. It takes up no space. It lubricates. It increases grinding forces thru cohesive forces. It increases viscosity and slurry density which distributes and floats(respectfully) abrasive particles well. It provides impact protection. It distributes well throughout batch. It allows higher rotation speeds without damaging your rocks. It allows rocks to grind directly against each other making efficient use of abrasives. It allows the use of larger abrasives by increasing slurry viscosity and density. Covington's description of their clay based slurry thickener: Old Miser is a binding agent designed to hold grit to a workpiece so that it is not thrown off by centrifugal force or washed away by water. This compound assists by quickly making a slurry and holding the grit to the stone thereby speeding up the process and saving grit. Old Miser is water soluble and washes off the specimen easily. Pays for its cost many times over in grit and time saved.
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on Jun 1, 2018 20:41:03 GMT -5
Yes James........for over a year now.
You'll find reference to "old Miser" in several threads I've started here at RTH..........every batch I start in rotary grinding stages, be it 60/90, 120/220 or 400 cycles has Miser.
"Pays for its cost many times over in grit and time saved."........you don't need to use very much of it either.....!
I Vibe quite a bit......even use it in 120/220, 400 cycles....... I have found that anything above 400 really doesn't need it in a Vibe.
"It increases viscosity and slurry density...." which accelerates the slurry activation, I'm all for speeding the process without sacrificing end result quality..!
Don't think you missed any of Old Miser's attributes.......A Covington Engineering secret sauce.....lol
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,563
|
Post by jamesp on Jun 2, 2018 8:01:38 GMT -5
Yes James........for over a year now.
You'll find reference to "old Miser" in several threads I've started here at RTH..........every batch I start in rotary grinding stages, be it 60/90, 120/220 or 400 cycles has Miser.
"Pays for its cost many times over in grit and time saved."........you don't need to use very much of it either.....!
I Vibe quite a bit......even use it in 120/220, 400 cycles....... I have found that anything above 400 really doesn't need it in a Vibe.
"It increases viscosity and slurry density...." which accelerates the slurry activation, I'm all for speeding the process without sacrificing end result quality..!
Don't think you missed any of Old Miser's attributes.......A Covington Engineering secret sauce.....lol
Far out. A slurry man. You should be on you way. I do want to say something about my clay types since you are a fan of Old Miser. Covington uses a specific clay. I forgot the geological term but it comes from a California location I believe. Run this thru your brain. Georgia a leading producer of one of the finest suspesion/slurry clays called kaolin. Suspendible platelets of high aluminum eroded felspar. Because the targeted kaolin is white it is used for suspensions in paint and ink in addition to massive slurry applications. It is also the source clay used in firing ceramic media due to a high aluminum content.(about 35% aluminum oxide alone) A massive vein of it occurs across the middle of Georgia. North of the white vein of white kaolin is red kaolin(Georgia red clay). Stained from heavy iron composition like Old Miser. Now to the point, the white kaolin comes no where close to sticking and distributing abrasive particles to the rocks in the barrel as the red version does. I have read but do can not seem to comprehend conductivity(increased by the iron content) as it relates to cohesive forces. I was curious if you could ask Covington engineer if their clay is red because of iron content and if so does the iron have a bearing on Old Miser's performance. Why am I making a deal about cohesive forces ? Because it sucks rocks together and increases grinding forces in a rotary. Compare mixing concrete before adding the Portland. It is easy. After adding the viscosity changes but also does the cohesive forces. As you pull the hoe thru the concrete the rocks grind against each other with much more force thanks to the Portland. By the same token I can run water slurry in my rotaries. When I add clay to thicken the slurry my motor gets hot because of increased friction.
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on Jun 2, 2018 12:03:56 GMT -5
Yes James........for over a year now.
You'll find reference to "old Miser" in several threads I've started here at RTH..........every batch I start in rotary grinding stages, be it 60/90, 120/220 or 400 cycles has Miser.
"Pays for its cost many times over in grit and time saved."........you don't need to use very much of it either.....!
I Vibe quite a bit......even use it in 120/220, 400 cycles....... I have found that anything above 400 really doesn't need it in a Vibe.
"It increases viscosity and slurry density...." which accelerates the slurry activation, I'm all for speeding the process without sacrificing end result quality..!
Don't think you missed any of Old Miser's attributes.......A Covington Engineering secret sauce.....lol
Far out. A slurry man. You should be on you way. I do want to say something about my clay types since you are a fan of Old Miser. Covington uses a specific clay. I forgot the geological term but it comes from a California location I believe. Run this thru your brain. Georgia a leading producer of one of the finest suspesion/slurry clays called kaolin. Suspendible platelets of high aluminum eroded felspar. Because the targeted kaolin is white it is used for suspensions in paint and ink in addition to massive slurry applications. It is also the source clay used in firing ceramic media due to a high aluminum content.(about 35% aluminum oxide alone) A massive vein of it occurs across the middle of Georgia. North of the white vein of white kaolin is red kaolin(Georgia red clay). Stained from heavy iron composition like Old Miser. Now to the point, the white kaolin comes no where close to sticking and distributing abrasive particles to the rocks in the barrel as the red version does. I have read but do can not seem to comprehend conductivity(increased by the iron content) as it relates to cohesive forces. I was curious if you could ask Covington engineer if their clay is red because of iron content and if so does the iron have a bearing on Old Miser's performance. Why am I making a deal about cohesive forces ? Because it sucks rocks together and increases grinding forces in a rotary. Compare mixing concrete before adding the Portland. It is easy. After adding the viscosity changes but also does the cohesive forces. As you pull the hoe thru the concrete the rocks grind against each other with much more force thanks to the Portland. By the same token I can run water slurry in my rotaries. When I add clay to thicken the slurry my motor gets hot because of increased friction. The next visit to Covington I'll see if I can catch up with Dan, ask him about the Old Miser......I know he had mentioned to me previously the it is an old proprietary product of theirs and that some of the ingredients were locally collected.......don't expect any trade secrets, but may be able to find out what type of clay is used.
What I understand and have knowledge of associated with slurry's, stems from my background in concrete/asphalt pavement analysis related to road construction. Most of the basic "physics" principals applied to sieve analysis, sand equivalence, abrasive resistance and aggregate quality/gradation, could be applied to that of barrel tumbling stone grinding........minus the binder, accelerators, emulsion applications. Tthose for stone grinding, we do, most likely rely on a different set of perimeters....on a different scale of application.....a cement mixer truck application or hydro pumping application comes to mind...!
As for how the specific gravity, viscosity and texture (slurry thickness) effects the balance and weight associated with the mix, causing the material to adhere to the stone, either reducing or increasing the friction within the application.......may have something to do with the water being separated (forced/squeezed) away from the stone......binding to stick, reducing or increasing the internal stone rotation speed........changing the load capacity/weight distribution.......which in-turn causes the energy required to rotate the container (barrel) to become more demanding on the motor.....thus, increasing the heat (due to friction) of the motor..........It's just a guess (in layman's terms), but it's my best guess.....lol
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,563
|
Post by jamesp on Jun 2, 2018 13:14:45 GMT -5
Excellent. I would love to hear what he has to say. I do want you to be aware of the effect of the red clay used here. If I were pushing the process I have found that a milk shake consistency is about the most aggressive grind. At a protective milk shake consistency and 80 RPM using 6 inch I.D. barrels I was getting complete breakdown of SiC 30 abrasive in 24 hours. All tests on coarse shaping were based on carefully scavenging all the left over abrasive after 12-24-36-48 hours. I thought that the most important criteria. One would think that the thick slurry would prevent abrasive breakdown - not. So if I was on the war path to get a load shaped quick I was doing 24 hour grit additions. Of course the slurry got to thick so I would dilute the top of the barrel with fresh water. Pour off the top where it was diluted and re-top it off with clean water and add more SiC 30. That way any abrasive that was not spent all the way was still in the barrel. After 5 to 6 days/abrasive additions I would do a complete clean out. Increasing to 80 RPM with the thick slurry allows me to know run 45 cent/pound bulk refractory SiC #4-#8-#16-#30- all mixed together. I had to go to HDPE barrels because of the super aggressive nature of the coarse SiC. Funny, let the bulk SiC run for 5 days and break down I could then go straight to the vibe with AO 500. The 80 RPM is a game changer. And I put glass microscope slides in the batch to test gentleness, they did not break. 85% barrel fill added with milk shake way makes for gentle conditions with even at 80 RPM. If not wanting to fool with grit additions every day or two I would run at 30 RPM and SiC 30 and weekend clean outs. The only faster grind I had was running 40% 50 grit fused SiC chunks from hammer broken SiC grinding wheels purchased at a junk yard. Those were hell on the PVC barrels, OK with HDPE barrels. Inefficient though because the SiC chunks shaped each other and spent the SiC faster. Bulk SiC - www.flickr.com/photos/67205364@N06/sets/72157683529500581Chunks of SiC grinding wheels - www.flickr.com/photos/67205364@N06/sets/72157649671884531Kaolin and red clay - www.flickr.com/photos/67205364@N06/sets/72157664920443825
|
|
tkvancil
fully equipped rock polisher
Member since September 2011
Posts: 1,547
|
Post by tkvancil on Jun 8, 2018 10:31:04 GMT -5
Very interesting thread ...
My two cents on ceramics in rotary rough grind ... I don't use them often in rough grind, generally when I don't have any better "filler" available. Example ... Was running some Moonstone, Obsidian and other softer stones, out of fresh rough of matching hardness, use large ceramics to get the last two weeks tumble time needed. Yes they do wear faster but hold up very well. As far as action in the tumbler goes it is much the same as adding "smalls". Put in a relatively high percentage of ceramic and it will slow down the grind just as will adding an extra amount of small rocks. From the pics I see here, all rough near same size, and the OP's stated intentions, ceramics seem a good choice to me.
As far as speeding up the coarse grind pre-shaping has the most influence. Weather it be cut and shaped rocks or glass pendants as discussed above. Already having the desired shape precludes the extended tumble time required for shaping. Next most important is how often fresh coarse grit is added. Obviously most of the cutting/shaping is done while the grit is still coarse. This is mute when running pre-forms with only one or two coarse charges. However a batch of crushed or hammer broken agate/jasper rough for example ... In a QT12 to get well rounded the way I like will take 3 to 6 months on the once a week cleanout schedule. During that week one will get 2 to 5 days of grinding with grit in the coarse range. The rest of the week is spent in medium to fine as the SIC continues to break down. Therefore if your tumbler and formula are breaking grit down past coarse in 3 days, changing or recharging every 3 days is in order. Doing so would cut tumbling time in half. Last part of the equation is the operators formula. Amount of water and grit, thickener or not, barrel size/shape and speed along with what's in the batch and how it's loaded are all part of the formula. Homemade tumblers with variable speeds and barrel sizes offer the widest range of grinding possibilities. Harder to change action in off the shelf tumblers but can be done.
|
|