pizzano
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Post by pizzano on Apr 8, 2018 19:46:25 GMT -5
Just finished cutting some Dolomite, Sphalerite, Smithsonite "laced" or otherwise embedded material.........some small slabs and quite a few 1" cubes.....:
Small Slabs & a few Cubes
I intend to use my polishing/grinding plate to smooth/round out and polish the small slab faces.......not for tumble.
Everything shown is approx. a 4.0 to 5.0 on the Mohs scale........I have about 4lbs of cubes and odd-balls I'd like to try to tumble.
I Have never polished or tumbled (vibe) material this soft. Only common Opal that was more on the 5.0 to 6.0 scale.....It was a learning experience that I will not soon forget........and much of it finally resulted in a very nice glass type shine.
I Know a few of you guys and gals have been down this road......Hope you'd like to share your experiences..........Thanks.
Note...: I use a bowl type vibe system.......and am all ears if this material could be staged 1 or 2 in a rotary......?
Note:
Edited......Looked up my records (thanks to the wife) and found that I had tried once to rotary polish Fluorite and Apatite together back in June 2017......not a good experience, but the Opal I remembered.......The Wife never forgets the stuff that doesn't meet her QC......lol.....for me, in my older age.....out-of-site, out-of-mind.......lol
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nchillbilly
starting to spend too much on rocks
Member since January 2018
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Post by nchillbilly on Apr 8, 2018 23:10:47 GMT -5
Good evening Joe. The material you're talking about polishing sounds very similar to the serpentinite I did a few weeks ago. I started mine in a rotary, and finished in a vibe (the one you turned me on to). I still believe much of the success I've had with softer material (serpentinite and obsidian) can be traced to using a high ratio of 4mm ceramic spheres, using a slightly thinner slurry, and adjusting my mix so that I've got good action without it being violent. The 4mm balls aren't as easy to find as the 2mm, but they're much easier to work with, and with the ratio at 50% of total load or higher, the stones just swim in them. I think they work very well. I believe you'd be happy with the outcome if you ever incorporated them into your mix. I still use the ceramic cylinders also, but at a lower ratio when I get to the polish stage. I'll use a higher ratio of cylinders during the initial grind, and lessen the ratio as I go. "Keep on rollin, rollin,rollin,rollin"
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Post by grumpybill on Apr 9, 2018 5:26:52 GMT -5
You might benefit from reading up on tumbling glass/obsidian, which is about the same hardness.
I've never intentionally tried to polish soft stones, but I've been experimenting with sea shell fragments for pendants (probably the same hardness as your stones) in a Lot-O vibe.
Because they don't need shaping, I don't do a course stage. When I load the bowl I try to fill every nook and cranny between the shells with small ceramic cylinders and polished pebbles ranging from pea to jelly bean size. Probably comes out to 50% or so small stuff. I start with a 12-18 hour run with 220 Sic, checking often after the first 10 hours. Too much time or using 120/220 wears them down too much. (Although, your rough stones might need that.) I follow that with 18-24 runs of 500, 1000 and polish. If I'm adding the shells as filler with hard stones, they skip the 1000 stage. Doesn't make a noticeable difference, so I'll probably skip it on the next shell-only run.
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pizzano
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Member since February 2018
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Post by pizzano on Apr 9, 2018 10:56:58 GMT -5
Thank you J.T. and Bill........I did a little research on fossil, obsidian and fluorite/calcite tumbling prior to posting this thread. Started the load around 10:30pm last night. Took some of your advise and started the batch in the vibe (all of my rotary barrels are currently working hard in 1st stage and at least two weeks away from being available). Will be checking the vibe again around noon today.
I'm trying a mix of 50% ceramics, 120/220 Sic for the first stage. If they look ready, intend to start 2nd cycle with 600 graded Sic and same amount of ceramics. Depending how that turns out (if I don't lose to much volume), I'll use 8F-800 Sic since I'm out of 1000......then I'll try some 1500 AO pre-polish and then Covington Gold #2 polish, all with ceramics.......The Gold polish has worked on everything I tried so far. It's 99% pure, 2-3 microns and 9Mohs micro-alumina, compares with Tin Oxide...........Maybe you guys can steer me in another direction if my plan seems to complicated.....?
Since this is an experiment, I saved 1/2 of what I had cut up for later......if this works out, I'll be cutting more and keeping the vibes busy while the barrels grind out Montana Moss and Mozambique I purchased a couple of months ago.....!
Thanks again guys....
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pizzano
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Member since February 2018
Posts: 1,390
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Post by pizzano on Apr 9, 2018 14:50:44 GMT -5
Came home for lunch......this is what the rock bug does to you.....lol
Rinsed and re-charged 1st cycle........they appear to be taking shape.....some loss of volume, reduced ceramic by an 1/8th......:
Gonna let them run another 8 to 10 hours in 120/220......try to reduce undulations and shallow seem fractures as much as possible to keep next stages "grit stick" to a minimum.......we'll see.
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tkvancil
fully equipped rock polisher
Member since September 2011
Posts: 1,547
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Post by tkvancil on Apr 9, 2018 15:32:01 GMT -5
If you have some small polished mohs 7 material available use it along with the ceramic media.
I run a Thumlers UV18. Never had enough "soft" stuff to fill it. Therefore all obsidian, and softer stones go in with agates and jasper. Always shines up for me. Even got a mirror like finish on Howlite recently this way.
I also use a thickener in all stages after 220. I use psyllium but borax is also effective. There is an OP on here who gets some of the most shiny obsidian you'll ever see, 50/50 small agates rest obsidian and psyllium thickener.
If you decide to rough some out in a rotary (someday) start with 220 and check often. Interested how your material roughs out in the vibe. Want to try the same sometime soon. Good luck it can likely be done.
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pizzano
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Member since February 2018
Posts: 1,390
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Post by pizzano on Apr 9, 2018 21:19:08 GMT -5
Thanks for the tips Ken........I thought about the agate chips as filler, but used all of the small stuff I had on the Moss and Moza tumbling right now. Didn't have enough ceramic when I started them.......I have a thickener I use with good results for all grinding stages, Covington Old Miser. Works well in both the vibe and rotary. So far have not had much trouble managing the slurry in this cycle, will see (around midnight) if it's time to proceed with stage 2....I'm off work tomorrow, so no need for sleep.....lol
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nchillbilly
starting to spend too much on rocks
Member since January 2018
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Post by nchillbilly on Apr 9, 2018 21:36:38 GMT -5
Thanks for the tips Ken........I thought about the agate chips as filler, but used all of the small stuff I had on the Moss and Moza tumbling right now. Didn't have enough ceramic when I started them.......I have a thickener I use with good results for all grinding stages, Covington Old Miser. Works well in both the vibe and rotary. So far have not had much trouble managing the slurry in this cycle, will see (around midnight) if it's time to proceed with stage 2....I'm off work tomorrow, so no need for sleep.....lol If you ever find yourself wanting to try the 4mm ceramic balls, I got mine from an ammo reloading supply outfit in Florida. They were previously used by them, cleaned and bagged. I bought 5lbs, but will probably get more at a later time. I don't run them in coarse, but I use them in all stages in the vibe. There is some pre-run cylinders and 2mm balls also, but the 4mm's make up the bulk of the media load. BTW, this ceramic is the polishing variety, not the cutting type.
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pizzano
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Post by pizzano on Apr 9, 2018 21:51:58 GMT -5
Thanks J.T.
I'm having pretty good luck with the angle ceramics - 1/4"x5/8" and 5/32"x5/16".......I have a inexpensive source a couple of miles from here. Good thing, because I go through a lot of it during the 60/80/90 and 120/220 stages. It lasts awhile for polishing stages.
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nchillbilly
starting to spend too much on rocks
Member since January 2018
Posts: 212
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Post by nchillbilly on Apr 9, 2018 22:00:16 GMT -5
Thanks J.T.
I'm having pretty good luck with the angle ceramics - 1/4"x5/8" and 5/32"x5/16".......I have a inexpensive source a couple of miles from here. Good thing, because I go through a lot of it during the 60/80/90 and 120/220 stages. It lasts awhile for polishing stages. I wish I could find another source for the 4mm's, they seem just a bit pricey to me. I think I gave $30 for 5 lbs, but I do really like how my tumbles have been turning out. The only issues I've had lately is being able to leave the rocks in the coarse grind long enough to get them really smoooooooth and free of crevices. I'm tickled with the shine. Good luck with yours, and be sure to show them off when they're done.
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pizzano
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Post by pizzano on Apr 10, 2018 12:16:24 GMT -5
2nd stage 600 Graded Sic has begun.......no pic's since they looked like the last photo, just more refined and a little more loss of volume.
I had a decision to make at midnight (run time at 26hrs)........after scrubbing and examination (naked tired eyes) did not notice major undercutting. There were the normal fractures seams where the change in elements occur, but the grit never settled deep and most just rinsed off/out without heavy brushing. I'd estimate more than 60% of the stones showed no visible "clinging or trapping" crevices........and surface transitions were pretty smooth to the touch.........
So the decision was do I leave the 40% in and remove the nice ones and add more ceramic, or do I leave them "all in" another 120/220 cycle risking more loss of volume and potential undercutting......?
Well, I left them all in, recharged the grit two teaspoons, added a touch of water (the slurry was just right).....and let them run until 6:00am (total 32hrs) this morning.
Dumped everything, scrubbed again, examined and started stage 2........from the looks of everything, I'll still have some trouble come polish stages, with fine hair line fractures that will collect polish, but the vast majority of the stones are smoothing out nicely........the proof will be in the polishing.
I'm home today, so I'll be able to baby sit the 2nd cycle.........have no idea how long this will take.......get the slurry right and maybe 12 hours....fingers crossed.
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Post by johnjsgems on Apr 10, 2018 13:37:02 GMT -5
Just throwing in a correction to avoid confusion. Covington Gold #2 is .5 micron. Gold #1 is 2-3 micron. The #1 would work very well in rotary and the #2 in a vibe. Any .5 micron or finer will work on a wide range of hardness in vibe tumbler or buff on cab machine. I have had best luck on soft stones with "Vibra Dry" from Diamond Pacific.
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pizzano
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Post by pizzano on Apr 10, 2018 14:01:21 GMT -5
Just throwing in a correction to avoid confusion. Covington Gold #2 is .5 micron. Gold #1 is 2-3 micron. The #1 would work very well in rotary and the #2 in a vibe. Any .5 micron or finer will work on a wide range of hardness in vibe tumbler or buff on cab machine. I have had best luck on soft stones with "Vibra Dry" from Diamond Pacific. Thank you John......I have both #1 and #2.......My memory ain't what it used to be....Like you said, #2 is what I use in the vibe...and will be using it on the polishing wheel I'm purchasing.........haven't tried the #1 in the rotary since I do all of my polishing now in vibes........bought both Gold's as a recommendation from the Covington folks after I purchased the vibe...... was gonna try the #1 on some all petri wood in the vibe once I get over the other projects......if no go, still have #2 which I know will turn out nice.
There's a lot to get confused about once you start learning and get more serious into this hobby......sorry if anyone was miss-led........!
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pizzano
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Post by pizzano on Apr 11, 2018 10:58:30 GMT -5
Started stage 3 - 8F 800 Sic (run time now at 45hrs).......my wishful 12hr scenario wasn't enough, let them run for 25hrs.......I had taken one piece that had been smoothed out nicely on one side (but had to many cracks), from the 1st stage and compared it to one from the 2nd stage by rubbing a silk hanky against them. There was a noticeable difference, so I moved on.
They hold the sparkle a little longer than last time wet and a little more vivid.
Since I'm not losing much volume now, I'll let the 3rd cycle run 24hrs........then maybe start pre-polish.
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pizzano
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Post by pizzano on Apr 12, 2018 13:18:19 GMT -5
Onto pre-polish stage.....Finished 3rd cycle (73hrs so far).....:
The Best of the Bunch Wet.......about 1/2 of the load.
Gonna use an AO that Covington sells as "Covington Tumbler Polish"....98% pure levigated alumina powder.....they say it's probably around a 1500-1800 size but seems no one knows for sure....lol
May wonder why I always refer to Covington.....?.....well, their establishment is only two blocks from my office and they treat me very well, even though I probably only spend a $100.00 every couple of months there....and salivate while checking out their equipment every time in. I also have a buddy who knows a few people there and has spent a bundle purchasing their Hoiz. Beveler/Grinder and Grinder/Polisher equipment.......he's a metal guy and also a gunsmith.
Really hope this material takes a shine........the next two steps are my "Waterloo"........If I'm gonna have problems, now's the time they will crop up.......lol
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pizzano
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Post by pizzano on Apr 13, 2018 12:24:30 GMT -5
4th Cycle pre-polish complete (97hrs thus far).......
I've lowered my expectations (not that they were that high to begin with)........this material (more than likely) will not vibe polish to the same standard as Agate, Jasper or Quartz.........regardless of time spent in the process.......been through an almost identical experience with Fluorite and Apatite. Although the Apatite finally took to a nice gloss (Cerium Oxide after AO polishing).
Dry.....
Dry......same lighting different background.....background with my phone camera changes the perspective quite a bit.
The photos do not pick up the sheen they display.....was very pleased that the polish did not embed into the crevices as I feared it would.
Onto the polish stage......will check them occasional as time permits........give a good look at 12hrs.........After 24hrs, if they haven't shined up some with the Gold #2, I fear a polishing wheel will be the only resource, if at all, they can be polished to a gloss.
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pizzano
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Post by pizzano on Apr 14, 2018 15:37:01 GMT -5
122hrs (5days total) into this project, I can finally say there is closure......at least for now.....:
Dry direct sunlight....with a few orphan pieces of Obsidian thrown in the polish last minute.
A few pieces that polished up...... under my shop lighting.......of course the photo doesn't reflect well.
Like suspected, the grainy sheeted material only polished well where cut along the harder seams.......the outer surfaces, in some cases, glossed up pretty nice also. Although, happy with the minimum polish "stick & embedding", the scrub effort after every cycle started to wear on me......lol......but, it helped.
There is an underlying reason, I intentionally did not mention (outside of my own curiosity), what compelled me to take this material on it's journey. When shopping this stuff around the local clubs trying to get information as to what it is. There were three mature gentlemen that I have chatted with previously about their clubs and rock stuff.........two of which have been involved with lapidary for more than 30yrs, once I told them where I collected the material, they seemed to lose interest and suggested that trying to polish it (with the equipment I'm using) may be "next to impossible".......Well, I love a good challenge.
They were nice enough to request I bring the "polished" results back for a "look-see".......kinda felt they were just being a little to patronizing due to my ignorance and lack of experience.......But, next week I'll be at their door steps, polished rocks in hand.
Hope, those of you who have followed this thread, enjoyed this story as much as I have putting it together......and now I have a log I can transfer to my Rock Files.....Much to learn and much to explore, so far loving this hobby.
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nchillbilly
starting to spend too much on rocks
Member since January 2018
Posts: 212
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Post by nchillbilly on Apr 14, 2018 22:20:15 GMT -5
122hrs (5days total) into this project, I can finally say there is closure......at least for now.....:
Dry direct sunlight....with a few orphan pieces of Obsidian thrown in the polish last minute.
A few pieces that polished up...... under my shop lighting.......of course the photo doesn't reflect well.
Like suspected, the grainy sheeted material only polished well where cut along the harder seams.......the outer surfaces, in some cases, glossed up pretty nice also. Although, happy with the minimum polish "stick & embedding", the scrub effort after every cycle started to wear on me......lol......but, it helped.
There is an underlying reason, I intentionally did not mention (outside of my own curiosity), what compelled me to take this material on it's journey. When shopping this stuff around the local clubs trying to get information as to what it is. There were three mature gentlemen that I have chatted with previously about their clubs and rock stuff.........two of which have been involved with lapidary for more than 30yrs, once I told them where I collected the material, they seemed to lose interest and suggested that trying to polish it (with the equipment I'm using) may be "next to impossible".......Well, I love a good challenge.
They were nice enough to request I bring the "polished" results back for a "look-see".......kinda felt they were just being a little to patronizing due to my ignorance and lack of experience.......But, next week I'll be at their door steps, polished rocks in hand.
Hope, those of you who have followed this thread, enjoyed this story as much as I have putting it together......and now I have a log I can transfer to my Rock Files.....Much to learn and much to explore, so far loving this hobby.
Isn't that one of life's great little victories, when you can accomplish something that someone else says ( or insinuates) that you can't? It's also a nice lesson for others out there that believe they can't because someone told them so. Tenacity is a great trait. Congrats.
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pizzano
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Post by pizzano on Apr 15, 2018 0:58:30 GMT -5
Thank You J.T.
This hobby certainly has it's challenges (and naysayers).....particularly if one seeks perfection........I learned at a very young age that there is only one "perfection" and man can only strive to come as close as his limitations will allow...!
Have yet to "perfect" anything I've accomplished.....there will always be room for improvement and growth. It's those challenges that motivate me to seek satisfaction in even the smallest attention to detail (on a budget)....lol......and my Wife's continued encouragement and support...!
Those stones taught me a lot.....from the collecting, identifying, preparation and ultimately the final tumble.......they aren't the most attractive specimens, particularly if you don't like brown........but my son (who discovered the material) has requested the pick of the litter and I'll happily oblige him. He's already asked me when I'm going to start more or if I'm considering trying to cab them........my response, "one thing at a time my boy".......
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