melf77
having dreams about rocks
Member since July 2017
Posts: 70
|
Post by melf77 on Jan 16, 2018 10:05:03 GMT -5
Hi all
It's been awhile since I've been on the boards. Still tumbling all the way through winter and let me tell you the lugging 5g buckets of slurry water up and down stairs to dump outside is a PITA, can't wait for summer.
Anyways, the title says it all. I'm trying to cut down on steps for materials 6 mohs or harder. I have been doing Xcoarse as my first step now going to coarse than medium, fine and polish. I am starting to let me rotary barrels run 3-4 weeks with the xcoarse and the coarse. Is it possible that XCoarse breaks down enough to where i could skip the course and just go straight to medium?
Your thoughts please
My rotary is the Thumler model B 15lbs. I do fill up to the 3/4 full.
Xcoarse 46/70 sic 3-4 weeks
Coarse 60/90 sic was 2 weeks
Medium 120/220 sic goes to vibe
fine 500 sic goes to vibe
than polish for anything 6mohs or higher
|
|
|
Post by Drummond Island Rocks on Jan 16, 2018 10:36:06 GMT -5
Hi all It's been awhile since I've been on the boards. Still tumbling all the way through winter and let me tell you the lugging 5g buckets of slurry water up and down stairs to dump outside is a PITA, can't wait for summer. Anyways, the title says it all. I'm trying to cut down on steps for materials 6 mohs or harder. I have been doing Xcoarse as my first step now going to coarse than medium, fine and polish. I am starting to let me rotary barrels run 3-4 weeks with the xcoarse and the coarse. Is it possible that XCoarse breaks down enough to where i could skip the course and just go straight to medium? Your thoughts please Different folks have different opinions of what corse, medium and fine are. It will help if you give details about the grits. In my case my steps are 46/70 SC, 120/220 SC, 500 AO, 1000 AO, .3 micron A/O and sometimes but not always a burnish run with borax. I do not use an extended run for my 46/70. Seven day clean outs and any that are ready each week go to 120/220 from there. Chuck
|
|
|
Post by Drummond Island Rocks on Jan 16, 2018 10:40:25 GMT -5
I almost forgot about barrel size. Barrel size plays a factor in grit breakdown. 46/70 in a 3 pound barrel will not break down in 7 days the same as it does in a 12 pound barrel. The larger diameter barrels will break down grit faster.
Chuck
|
|
|
Post by rmf on Jan 16, 2018 10:41:10 GMT -5
melf77 It would be better if there was some more info. Type of tumbling drum for example, What grit size is Xcoarse and what size is coarse and what size is medium. But making some assumptions and working from my experience here is my opinion. Assuming a Lortone rubber type barrel and Xcoarse is => than 46-70 grit (46-70 is a SiC split of grit that contains everything from 46 grit to 70 Grit). If you are tumbling 3 to 4 weeks in Xcoarse then when you get done wash the tumbling contents out (in a screen) over a 5 gal bucket allowing the water to swirl (like a toilet) then remove the rocks and pour off the muddy water slowly. If you have Xcoarse grit in the bottom of the bucket then you know how much has broken down by comparing how much you put in. (don't forget to reuse the grit) chances are that tumbling for 3-4 weeks has done a fine job and you can move on to medium grit (assuming this is a split in the 180-280 grit range). Xcoarse and coarse are for rounding the rocks which is I assume why you are tumbling for 3-4 weeks to get them as rounded as you like. This is exactly what I do. Once they are rounded the medium crits only job in the world is to remove the scratches from the previous grit. In this case one week should do it in medium and 1 week in fine then on to polish. I knew a commercial tumbler that used steel pipe for his barrel and put in 1# of SiC 46-70 grit for each 7# of rock. He then tumbled for 30 days and put them in polish. He always got a good commercial polish on agates and jaspers. Hope it helps.
|
|
melf77
having dreams about rocks
Member since July 2017
Posts: 70
|
Post by melf77 on Jan 16, 2018 10:55:43 GMT -5
Oh Geez, your both right- hit myself on the forehead, didn't even think to include the numbers or what tumblers I'm working with, might help.
My rotary is the Thumler model B 15lbs. I do fill up to the 3/4 full. Xcoarse 46/70 sic Coarse 60/90 sic Medium 120/220 sic goes to vibe fine 500 sic goes to vibe than polish for anything 6mohs or higher
|
|
melf77
having dreams about rocks
Member since July 2017
Posts: 70
|
Post by melf77 on Jan 16, 2018 11:01:23 GMT -5
So far I like what you are both suggesting. I was just wondering if I could skip the coase and go right to the 120/220 sic when I was happy with the shape.
I do do more steps in between than i mentioned above, like running a cleaning borax quick cycle between steps and I have to burnish after polish. I did notice a difference with my tap water and quality of polish.
Thanks guys for being so helpful with the limited info I gave out.
|
|
melf77
having dreams about rocks
Member since July 2017
Posts: 70
|
Post by melf77 on Jan 16, 2018 11:03:58 GMT -5
melf77 If you have Xcoarse grit in the bottom of the bucket then you know how much has broken down by comparing how much you put in. (don't forget to reuse the grit) Yeah, I do have leftover grit when I was doing cleanout at the 2 week intervals, reason why i am now extending it to 3-4 weeks and plus it's winter/snow for me and those friggin buckets, lol. Does 47/60 sic ever breakdown???
|
|
nileriver
off to a rocking start
Member since December 2016
Posts: 22
|
Post by nileriver on Jan 16, 2018 12:12:46 GMT -5
After some postings by jamesp a few weeks back, I ordered some AO 220 from eBay with a link he provided in the post. My results were as he had reported for himself, ie: 1) Extended time in the rotary with extra coarse (46/70 SiC, or whatever coarse SiC you like) 2) Rocks that are ready to move on go to a vibe with the AO 220. After about 48 hours, they begin to shine. 3) 24-48 hours in the vibe with whatever polish you have.
The AO 220 does seem to take care of the scratches, even from extra coarse SiC. Then it (the AO 220) apparently breaks down to finer and finer AO as time in the vibe goes on. According to jamesp, if left in longer, you may eventually get a finished shine. But I went ahead and moved them to an actual polish stage when they began to get shiny in the AO 220.
I think that your 220 SiC would also remove the scratches from the 46/70, without having to use the intermediate 60/90. And to even eliminate another step (500 SiC), consider using AO 220 instead of the SiC 120/220
|
|
melf77
having dreams about rocks
Member since July 2017
Posts: 70
|
Post by melf77 on Jan 16, 2018 14:11:18 GMT -5
After some postings by jamesp a few weeks back, I ordered some AO 220 from eBay with a link he provided in the post. My results were as he had reported for himself, ie: 1) Extended time in the rotary with extra coarse (46/70 SiC, or whatever coarse SiC you like) 2) Rocks that are ready to move on go to a vibe with the AO 220. After about 48 hours, they begin to shine. 3) 24-48 hours in the vibe with whatever polish you have. The AO 220 does seem to take care of the scratches, even from extra coarse SiC. Then it (the AO 220) apparently breaks down to finer and finer AO as time in the vibe goes on. According to jamesp, if left in longer, you may eventually get a finished shine. But I went ahead and moved them to an actual polish stage when they began to get shiny in the AO 220. I think that your 220 SiC would also remove the scratches from the 46/70, without having to use the intermediate 60/90. And to even eliminate another step (500 SiC), consider using AO 220 instead of the SiC 120/220 Thanks, will root out his thread and go over it. Will also look into AO grit. I would have no problem switching to AO 220 and just letting it run longer in the vibe, if i get those results. May have to pick up a lb to test it out fromEbay, thanks.
|
|
|
Post by rmf on Jan 16, 2018 16:07:41 GMT -5
Oh Geez, your both right- hit myself on the forehead, didn't even think to include the numbers or what tumblers I'm working with, might help. My rotary is the Thumler model B 15lbs. I do fill up to the 3/4 full. Xcoarse 46/70 sic Coarse 60/90 sic Medium 120/220 sic goes to vibe fine 500 sic goes to vibe than polish for anything 6mohs or higher melf77 For the softer rocks like the mohs 6 (glass for example) the 46/70 may be too coarse and grind too much away in 3-4 weeks but I would grind anything till it was rounded as much as I like soft or hard then stop. I would adjust the length of tumbling time to the shape I like. For myself I only use 46/70 because it is cheaper and because on agates it is faster. It will eventually break down even with rocks that are hardness of 6 but it may over grind before it breaks down. So I would just recover it and not worry about it. the big issue is when you get to the finer grits make sure you tumbler is still 75-85% full to prevent crazing of the edges on softer stones. Also, 20-25% fines (-1/2") helps too. Cushion well in polish with plastic pellets, wood etc as needed. You sound like you know what you are doing and there has been a lot of good advice given above as well. You probably do not need both 46/70 and 60/90. I like Coarse in rotary and finish in vib as well.
|
|
|
Post by Lapidaryrough / Jack Cole on Jan 16, 2018 17:03:55 GMT -5
40/70 & break out the cement mixer, time to rough up silicates. Gavel for the medium.
I have a octagon 11" x 24" rotary 17 RPM. i use 60/90 for 3 - 4 week runs. and add more 60/90 - I run thicker muddier slurry then most do. If I hear rock dinging around on each other add more water. As the load runs into weeks i sort out and add more rock grit. when i have a bucket full. Then the grit change to 80 grit for weeks. sort as needed.
80 grit after 3-4 weeks running well break down to 400 - 600 grit or finer. 40/70 & 60/90 in a tumbler less then 20 lb. loads, well don't count on the grit changing much.
I too use vibra tumblers, a VSV-45 an a double VT-12. fire agate polishing.
The cement mixer does the best rough tumbling with pillow Basalt gavel from the NW Oregon. Very high in silica. Seem slow toss in silica grinding wheels broken up 2"x2" and fine to, Remove the LEAD CENTER in wheel!
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,159
|
Post by jamesp on Jan 16, 2018 23:41:27 GMT -5
After some postings by jamesp a few weeks back, I ordered some AO 220 from eBay with a link he provided in the post. My results were as he had reported for himself, ie: 1) Extended time in the rotary with extra coarse (46/70 SiC, or whatever coarse SiC you like) 2) Rocks that are ready to move on go to a vibe with the AO 220. After about 48 hours, they begin to shine. 3) 24-48 hours in the vibe with whatever polish you have. The AO 220 does seem to take care of the scratches, even from extra coarse SiC. Then it (the AO 220) apparently breaks down to finer and finer AO as time in the vibe goes on. According to jamesp, if left in longer, you may eventually get a finished shine. But I went ahead and moved them to an actual polish stage when they began to get shiny in the AO 220. I think that your 220 SiC would also remove the scratches from the 46/70, without having to use the intermediate 60/90. And to even eliminate another step (500 SiC), consider using AO 220 instead of the SiC 120/220 AO 220 and AO polish in vibe after most any coarse SiC is working repeatedly. With Mohs 7 rocks it is always a quick vibe cycle 1.5 days in 220 and 18 hour in AO polish. All this discussion about SiC 30-46-60-80-90, beware that a barrel tumbler has limited grinding force so the scratches and pits from the the SiC can only be a minimum of depth.
|
|