|
Post by HankRocks on Apr 21, 2019 9:24:32 GMT -5
I agree with those who've written that there are too many variables to give a definitive answer. I'll use my experience with course grinding in a rotary to show why: I don't use a set amount of "time" to determine when to do cleanouts. I open the barrels every few days and rub some slurry between my fingers. If I feel grit, they run longer. If the slurry feels smooth/creamy, I do a cleanout. It can take anywhere from 4 days to 10 days to reach that smooth/creamy stage, even with the same barrel and the same type/amount of grit. The variables seem to be the types, sizes and weights of the loads. For me, Rock Tumbling is like making a Soup or a Stew. There are no hard rules for how much of anything goes in or even how long it needs to cook, just some guidelines. Most are all seasoned to taste and it's ready when taster declares it so. Experience of the Cook is the important factor. Same thing in tumbling. I vary the amount of grit by what type of rocks. Hard agates and hard Jaspers, more grit. Slabs and pre-forms with lots of filler less grit maybe a bit more time. Even then I separate my preforms by hardness which I can distinguish during the grinding stage. For those softer preforms I skip the Coarse Stage and go straight to 220. For the softer pre-forms I never add larger Brazilian slabs, Those would go in with the harder preforms. Grinding a rock or a preform is one good way to determine a rocks hardness. It's all about learning, experimenting if you will, with the rocks and their hardness and the particulars of your equipment.
|
|
victor1941
fully equipped rock polisher
Member since November 2011
Posts: 1,978
|
Post by victor1941 on Apr 21, 2019 10:38:48 GMT -5
I like the positive answers for the question of how fast does a specific grit break down over time when used as a rock abrasive. I would use a ball mill with AlO balls and SiC with known grit size and water and grind and sample at intervals to determine the breakdown rate. I would measure all weights and sizes and have a small random SiC sample placed on a grid and photographed. Remove at intervals and sample same number of particles for size. I did an experiment at college where we had to make slip with specific particle sizes using screen separators to make sure the particle size was correct. We dried the sample and screened. I think that a controlled test for each machine type is possible to determine the rate of breakdown and then test with your rock to see how it breaks down. Maybe some of you know someone in a tech college would use this as a student experiment.
|
|
Wooferhound
Cave Dweller
Lortone QT66 and 3A
Member since December 2016
Posts: 1,423
|
Post by Wooferhound on Apr 21, 2019 11:15:49 GMT -5
|
|
|
Post by Rockindad on Apr 21, 2019 11:57:02 GMT -5
Thanks, I've seen your first thread- I have something similar (I put an extra laundry sink in our basement that currently drains into a series of buckets). I understand grit and polish breakdown, we were just wondering if anyone actually verified the rate that it occurs.
|
|
|
Post by Rockindad on Apr 21, 2019 12:05:32 GMT -5
I agree with those who've written that there are too many variables to give a definitive answer. I'll use my experience with course grinding in a rotary to show why: I don't use a set amount of "time" to determine when to do cleanouts. I open the barrels every few days and rub some slurry between my fingers. If I feel grit, they run longer. If the slurry feels smooth/creamy, I do a cleanout. It can take anywhere from 4 days to 10 days to reach that smooth/creamy stage, even with the same barrel and the same type/amount of grit. The variables seem to be the types, sizes and weights of the loads. For me, Rock Tumbling is like making a Soup or a Stew. There are no hard rules for how much of anything goes in or even how long it needs to cook, just some guidelines. Most are all seasoned to taste and it's ready when taster declares it so. Experience of the Cook is the important factor. Same thing in tumbling. I vary the amount of grit by what type of rocks. Hard agates and hard Jaspers, more grit. Slabs and pre-forms with lots of filler less grit maybe a bit more time. Even then I separate my preforms by hardness which I can distinguish during the grinding stage. For those softer preforms I skip the Coarse Stage and go straight to 220. For the softer pre-forms I never add larger Brazilian slabs, Those would go in with the harder preforms. Grinding a rock or a preform is one good way to determine a rocks hardness. It's all about learning, experimenting if you will, with the rocks and their hardness and the particulars of your equipment. This is what does it for me. I like the challenge of figuring out what works with our setup. We currently have 4 rotary (three different sizes) barrels spinning and they all behave a little differently. Most of my questions about tumbling will be more about different peoples theories and reasoning versus how someone actually does something. If there was one magical recipe I could follow and get perfect results each time I would have lost interest already. Thanks, Al
|
|
|
Post by Rockindad on Apr 21, 2019 12:09:05 GMT -5
I like the positive answers for the question of how fast does a specific grit break down over time when used as a rock abrasive. I would use a ball mill with AlO balls and SiC with known grit size and water and grind and sample at intervals to determine the breakdown rate. I would measure all weights and sizes and have a small random SiC sample placed on a grid and photographed. Remove at intervals and sample same number of particles for size. I did an experiment at college where we had to make slip with specific particle sizes using screen separators to make sure the particle size was correct. We dried the sample and screened. I think that a controlled test for each machine type is possible to determine the rate of breakdown and then test with your rock to see how it breaks down. Maybe some of you know someone in a tech college would use this as a student experiment. Would be interesting for sure. Unfortunately/Fortunately I do not see an open tumbler in our future for a long time. Maybe add a tumbler just for experiments? I would have to hide that one, my wife already thinks we are getting a little nutty. Al
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Apr 21, 2019 20:52:14 GMT -5
I don’t know the answer to your question, but I think it varies according to the hardness of the material that you’re tumbling. Softer rocks won’t break the grit down as fast as harder materials. There are probably other variables too. So I don’t think there probably is a single answer. I think jamesp is probably the best guy to answer your question. I’m interested to see what you come up with after your experiment. Thanks Rob, I may have an answer/opinion for that one. Maybe consider using a form of experimental methodology often used in engineering called 'limits' to help answer a question like this. limits or extremes: If a vibe was full of Mohs 2 soapstone you can rest assured the Mohs 8 abrasive will last a long time, break down will be very slow. If this vibe is full of large, dense, tough Mohs 8 garnets you can be assured the Mohs 8 abrasive will break down very quickly. Or if one vibe's hopper is 12 inches tall verses another at 4 inches tall the taller 12 inch hopper will crush the abrasive faster due to the higher weight column. The variable of power must be considered though. Some vibes simply have more power. Vibes vary from 1/20 hp for 4 pounds of rock to 1/3 hp for 8 pounds of rock. Or 1/20th horsepower for 4 pounds verses 1/6 horsepower for 4 pounds. Keep in mind those general statements(grit breaking down by half.....) are probably made by lapidarian folks whom are referring to Mohs 7 stones and alum ox/silicon carbide abrasives. (no one in their right mind would be running soapstone in a vibe !) Those general statements are likely close to true. I can say for sure it takes over twice as long for SiC 60 to break down in a rotary rolling Mohs 5 glass as it does rolling Mohs 7 Rio Grande agates and woods. And that hard media like ceramics or quartz pea gravel needs to be run with glass in a vibe or else the abrasives will break down too slow.
|
|
|
Post by As I in does tries! on Apr 22, 2019 1:09:57 GMT -5
Greetings the people that have Viking Vibrasonic vibes such as myself and James P the motors consume 1.5kWh (1.8hp) per hour that is 6 times more power than a 0.25kWh (1/3HP) motor!
Also you can use coarse grit in the Viking Vibrasonic vibes if you wish, but leads to grit being imbedded into the liner an excess wear!
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Apr 22, 2019 1:46:41 GMT -5
Greetings the people that have Viking Vibrasonic vibes such as myself and James P the motors consume 1.5kWh (1.8hp) per hour that is 6 times more power than a 0.25kWh (1/3HP) motor! Also you can use coarse grit in the Viking Vibrasonic vibes if you wish, but leads to grit being imbedded into the liner an excess wear! My Vibrasonic has a 1/3 hp motor As I in does tries!. 3450 RPM. twin shaft. I never knew they made them with any other motors.
|
|
|
Post by As I in does tries! on Apr 22, 2019 3:36:30 GMT -5
Greeting James P, remember what yours was listed as Viking Vibrasonic VT8 (a pair of 4lb hoppers), but you have a 14lb hopper.
The original Invoice was Viking Vibrasonic VT35 with 35lb, 14lb hoppers. the last Invoice was Viking Vibrasonic VT14 with 14lb and a pair of 6lb hoppers.
The original buyer sold the 35lb and one 14lb hoppers 25 years ago and when I bought the machines there was only the 14lb a pair of 6lb hoppers and I Have had them about 8 years already.
The motors are 230Volt 50Hertz at 3000 RPM twin shafts non USA power runs slower due to 50 hertz. Whereas your motor will be 110Volt 60Hertz at 3450 RPM twin shafts, however if you use a wattman power meter in-line it will tell you how much power it consumes, on mine it's 1.5kWh which is 6 times that of 0.25kWh (1/3HP) motor.
For me: 1 hour running Viking Vibrasonic vibe consumes 1.5kWh of Electricity £0.192 ($0.249). 1 hour running cabochon machine consumes 1.5kWh of Electricity £0.192 ($0.249). 1 hour running Plasma tv and Sky+ consumes 2kWh of Electricity £0.257 ($0.333). 1 hour running games computer with 22" IIyama CRT consumes 0.35kWh of Electricity £0.045 ($0.054).
|
|
gatorflash1
spending too much on rocks
Active in Delaware Mineralogical Society, Cabchon Grinding and Polishing, 2 Thumlers B's and a UV-18
Member since October 2018
Posts: 375
|
Post by gatorflash1 on Apr 22, 2019 7:35:42 GMT -5
I like the positive answers for the question of how fast does a specific grit break down over time when used as a rock abrasive. I would use a ball mill with AlO balls and SiC with known grit size and water and grind and sample at intervals to determine the breakdown rate. I would measure all weights and sizes and have a small random SiC sample placed on a grid and photographed. Remove at intervals and sample same number of particles for size. I did an experiment at college where we had to make slip with specific particle sizes using screen separators to make sure the particle size was correct. We dried the sample and screened. I think that a controlled test for each machine type is possible to determine the rate of breakdown and then test with your rock to see how it breaks down. Maybe some of you know someone in a tech college would use this as a student experiment. I like this suggestion.
|
|
|
Post by parfive on Apr 22, 2019 13:55:36 GMT -5
1 hour running Plasma tv and Sky+ consumes 2kWh of Electricity £0.257 ($0.333). Does that thing heat the living room too?
|
|
|
Post by Rockindad on Apr 22, 2019 20:22:08 GMT -5
The Original Post with my takeaways in yellow:
Disclaimer: Please take no offense, this is not an attack on anyone's beliefs, we are just curious.
We have been unsuccessful in finding anything but the oft-repeated forum posts containing "grit breaks down by half every 24 hours in a vibratory tumbler". Looking for another source like a book, article, member here who has the means to verify this, etc. Gathering from the posts here that no one else has seen or documented this either other than by feel and/or visual observation, I am not discounting the value of this as it is what I am going by also. Considering the experience and longevity of some of the posters here this info probably does not exist, regardless of anyone's specific setup.
We are not necessarily doubting this is the case but do not take it as gospel either. Just a guess, but I do think the vibe we use (Thumler's UV-10) breaks down grit by half in close to 24 hours. Only a guess as I am going by what I see in my cleanup sink and feel as I rub the dried slurry in my fingers. Second part of that guess is that even though we run a lot of soft materials our heavy usage of mixed ceramics makes up for it when it come to grit breakdown.
Reason for asking is that we wanted to run some experiments and are looking for some verifiable information before we put a plan together.
The experiments mentioned here have to do with transitioning to the next finest grit/polish with as small of a leap as possible. For instance going from 500AO to whatever polish you want to use. Ideally, having an established rate of particle breakdown would allow you to simply do the math to figure out approximately when that 500 has broken down to the size of the polish particles, allowing a "seamless" transition.
I used to do a lot of woodworking which turned into a business and unfortunately had the opportunity to see many pieces that were built wonderfully by others but were ruined by a poor finish. There were a few times I had to turn away the work of refinishing as it would cost more than what the piece was worth. This was almost always due to poor surface preparation/sanding. No one skips the coarse sanding or the finish sanding, it's all of those "transitions" in between that can make a huge difference. It was a conversation with my son A.J. about this and comparing the similarities between sandpaper grits (not a perfect comparison as sandpaper does not breakdown in the same manner as tumbled grit) and what we use for tumbling that lead us to start this thread.
Just wondering if this is something that was thrown out there by one or two people and it spread like a wildfire or if it was actually documented somewhere.
Probably just started as a "close enough" observation by some and many others saw the same thing and it became a rule of thumb as someone mentioned earlier. I agree with those of you who said this would be an interesting experiment. It definitely got my wheels turning and putting one together would not be that difficult. Before I turned to a life of working with my hands I was pursuing a life in academia as a research scientist, albeit in the fields of human behavior but research methods are somewhat universal. Maybe someday.
Thanks, Al & A.J.
This still applies- thanks to all who contributed positively to this thread!
|
|
pizzano
Cave Dweller
Member since February 2018
Posts: 1,390
|
Post by pizzano on Apr 22, 2019 22:48:40 GMT -5
I had been saving the following comment and info links on the whim that the OP would ultimately "summarize and conclude" that the "truth" sought would be difficult to ascertain due to the vast complexity of the subject matter, generally left to the more "scientific" arenas of web forum conversation....
To the OP.......I apologize for appearing "confrontational" with regards to the "pointed line" of questioning and the definitive approach taken whilst trying to ascertain (ferret out) and understand a purpose, reason or goal for your quest.........having been preempted by the statement that "one was considering" doing some of their own experimentation"........to find the "truth".
I had no "horse in this race" and took the disclaimer at face value (although it did set a tone of apprehension)........therefore, none of the conversation was ever intended to be a "personal attack" nor did I ever feel "personally" offended....!
That said........being of a "science" minded analyst.........I have several "material properties" and abrasives "bookmarks" (stored here on my PC) that I use from time to time as reference while "on the job", that I can share with you, if you are so inclined.
Here's a couple that may help anyway, with "principals and standards" related to your subject matter......it is, by any stretch of the imagination, a "science" within it's self....!
www.asminternational.org/documents/10192/3447544/06958G_Chapter_4.pdf/a6cda448-291f-491b-bf6f-456322c4e386
textbooks.elsevier.com/manualsprotectedtextbooks/9780750663809/Static/index.htm
|
|
|
Post by parfive on Apr 23, 2019 0:09:53 GMT -5
Speaking of “subject matter” that ain’t that “difficult to ascertain” . . . Here's a couple that may help anyway, with " principals and standards" related to your subject matter......it is, by any stretch of the imagination, a "science" within it's self....!
|
|
|
Post by arghvark on Apr 24, 2019 8:06:34 GMT -5
Purely qualitative so possibly of not much use here, but FWIW: in my Lot-o filled with agates and jaspers, around 30% 3/8" ceramic cylinders, and 2 tbsp of 120/220 SiC, after 24 hours a "touch test" - rubbing slurry between fingers - detects no discernible grit at all. So in these conditions seems faster than breakdown by half in 24 hours.
Argh
|
|
|
Post by Rockindad on Apr 24, 2019 21:13:30 GMT -5
I had been saving the following comment and info links on the whim that the OP would ultimately "summarize and conclude" that the "truth" sought would be difficult to ascertain due to the vast complexity of the subject matter, generally left to the more "scientific" arenas of web forum conversation....
To the OP.......I apologize for appearing "confrontational" with regards to the "pointed line" of questioning and the definitive approach taken whilst trying to ascertain (ferret out) and understand a purpose, reason or goal for your quest.........having been preempted by the statement that "one was considering" doing some of their own experimentation"........to find the "truth".
I had no "horse in this race" and took the disclaimer at face value (although it did set a tone of apprehension)........therefore, none of the conversation was ever intended to be a "personal attack" nor did I ever feel "personally" offended....!
That said........being of a "science" minded analyst.........I have several "material properties" and abrasives "bookmarks" (stored here on my PC) that I use from time to time as reference while "on the job", that I can share with you, if you are so inclined.
Here's a couple that may help anyway, with "principals and standards" related to your subject matter......it is, by any stretch of the imagination, a "science" within it's self....!
www.asminternational.org/documents/10192/3447544/06958G_Chapter_4.pdf/a6cda448-291f-491b-bf6f-456322c4e386
textbooks.elsevier.com/manualsprotectedtextbooks/9780750663809/Static/index.htm Out of respect to the Moderators and the many helpful and friendly members here I have avoided this post for a couple of days and will only say maybe you need to get over yourself. Two things I try to keep in mind especially while online: 1) Treat others with respect, and 2) Do not speak to someone differently than I would if we were face to face. Your posts speak for themselves. I can say with great certainty that you would not have taken this tone with me if I were in front of you. Al
|
|
fivedirections
starting to shine!
Member since December 2021
Posts: 32
|
Post by fivedirections on Mar 25, 2022 1:27:05 GMT -5
The way I have been trying to approach this is collecting dabs of the slurry at different time and letting them dry on glass slides. When I find a cord to make the light work in my microscope I cab hopefully see what happens and share images or a report.
I hope to see some cool stuff no matter what.
Anyone tried that?
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Mar 27, 2022 9:34:22 GMT -5
Unfortunately tumbling can be a difficult process with many avenues to reach a common goal. Thru my extensive experiments I ran into many that disagreed with some of my processes. Many people hold fast to their ideas and methods. That should be respected. I stayed objective and tried to avoid conflict but listened to advise carefully. There are short cuts and tricks. They are worth pursuing. My final favored outcome looks nothing like any other recipe. That's just the way it is. Said final recipe works for my machine, assortment of tumble sizes and types, slurries and other variables.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,155
|
Post by jamesp on Mar 28, 2022 8:31:55 GMT -5
The way I have been trying to approach this is collecting dabs of the slurry at different time and letting them dry on glass slides. When I find a cord to make the light work in my microscope I cab hopefully see what happens and share images or a report. I hope to see some cool stuff no matter what. Anyone tried that? Great point, without a microscope it would be difficult to quantify small particle breakdown at the AO 500 level. I say this because it is not easy to photograph nor quantify polish quality due to several variables. For what it is worth I illustrated the breakdown of SiC 30 particles using a white background in extreme rotary conditions since SiC 30 is large enough for the human eye to see. We do spend most of our time coarse grinding so why not investigate this step. I would be glad to post my experimental methodology, process and photos if deemed pertinent to this thread. For those interested: The surprising conclusion was severe breakdown of SiC 30 after 12 hours at 60 rpm, well tuned slurry, a 6" barrel, and a broad mix of Mohs 7 rocks averaging 1.5 inches in size. Complete breakdown after 1.5 days/36 hours which taught me I needed to(or should) refresh/add coarse grit on much shorter intervals. To remove the entire batch of used SiC 30 after 12 hours of run time a meticulous separation and screening process was followed. To get an accurate assessment of the abrasive breakdown this was deemed necessary. SiC smaller than 500 is not going to shape rocks anyway so that was the screen cut off size.
|
|