julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 27, 2009 13:34:31 GMT -5
Hello everbody!
I just joined this group this morning, and I am loving all the good input and topic threads.
I want to use my tumble-vibe to polish cab preforms that I generally rough out to 280grit, while babysitting my slab saws. Ive already learned a lot from reading the vibratory tumbling section. I am in the market for a new 10" bowl or two, for my ray-tech tumble-vibe.
Here's my questions:
1. Is this a bad idea, in general? I would be doing nice but not super-valuable cabs, of a variety of agate, jasper, and jasp-agates, all of similar hardness. These cabs would be for use in wire-wrap applications for the most part, I would suppose.
2. There is usually the remnants of a few 120g scratches left on the preforms, even tho I am generally pretty satisfied with the dome geometry and general shape of the cabs. should I start out with 400-600g anyway, or something a little coarser?
3. Ive heard that some folks have super glued cabs back to back to preserve girdle integrity, and prevent undue grinding away of the general shape of the cab. Is this a must-do?
4. Is 1/4" to 1/2" beach agate suitable as a filler for this job? Or should I try to use just the cabs and grit, and work on the proper water content to promote good motion?
5. Any hot tips on where to find additional 10" bowls?
Thanks Everybody!
Thomas Clark
julie-tom on ebay
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Post by Toad on Oct 27, 2009 15:35:43 GMT -5
I think a lot of folks here finish cabs in a vibe. But it might just be for pre-polish/polish. I don't recall. They'll chime in eventually. You also might check the cabbing board as I think that's where the thread was. Might have to go a few pages down.
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Post by Toad on Oct 27, 2009 15:58:03 GMT -5
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Post by deb193redux on Oct 27, 2009 16:49:57 GMT -5
I pretty much only tumble finish.
If you need girdles, and plan on bezel settings, you really can't do this. The back-to-back glue might help, depends on you tolorances.
If you want both sides finished to wrap or affix a bail (drill or glue) you can do this.
You must have a full range of size and shape, and this is even more important with cabs that are flatish. Smaller than 1/4" is needed.
Some beach agate is OK, but also consider some small ceramic pellets to help carry the grit and to keep cabs from sticking together.
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Post by frane on Oct 27, 2009 21:06:38 GMT -5
I think when it comes to polishing my cabs in the vibe, I first run some other stones that will be filler in the 120-220 for a few days just to make sure they are not sharp and will damage your cabs. I generally put cabs in with the 500 or even the 1000 if I have processed it further than the 325 flat lap. Others I have just not been happy with the polish that I have gotten with the flat lap and I will throw them in the polish stage of the vibe and they turn out great! As long as you have similar hardness, it should be fine and I think you will like the results!
Fran
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Post by rocklicker on Oct 28, 2009 0:48:58 GMT -5
What about finishing up to 1200 or 3000 then putting the cabs in the vibe with prepolish then polish? It would seem that you could keep the shape intact better that way. Wait, that's what Toad was talkin about. I have to admit I am new to the whole vibe scene so that's just speculation. I am thinking of trying to finish cabs in the vibe once I get the hang of it.
Steve
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 28, 2009 10:15:33 GMT -5
Thanks folks for the input, thus far! Im grinding a batch of mix sized filler so far, and and some practice end-cuts and little slab corners. When those get fairly rounded, I will add some preform cabs, and see how things progress. I started with 60-90 yesterday, and it should take a few days? for that to break down to a finer grit slurry. Is it possible to get all the way to prepolish with a continuous run of the 60-90 as the grit breaks down? Ive been reading postings about doing the finish work in a rotary, for the most part. does anybody work with a series of bowls for each phase and finish out with a vibratory system?
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Post by Toad on Oct 28, 2009 10:22:34 GMT -5
60/90 might work in just a few days on preforms. Rough rocks will probably take months. There have been some folks that have just let their rocks run and run from 60/90 and just keep letting the grit break down. I think they liked the results, but I can't find the threads. Someone else may have more luck. Not sure how well it would work with rough rock - and it would definitely be slower than regular recharging. But if you're not in a hurry and want to save money, why not give it a try.
I only do the 60/90 phase in a rotary - to get the nice shaping effect. All subsequent phases are in a vibe. Usually use a different bowl for each phase, but I'm thinking of going to one for all the grinding and one for polish.
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Sabre52
Cave Dweller 
Me and my gal, Rosie
Member since August 2005
Posts: 20,497
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Post by Sabre52 on Oct 28, 2009 15:02:44 GMT -5
Steve makes a very good point. Even in the vibe which tends not to alter shapes much, if your cabs bog down just a bit, even the fine 120/220 grind can seriously alter the stones contours. I manage to get a couple of stones screwed up in the vibe fine grind phase every time. Once the fine grind removes your scratches though, the next stages ( tripoli prepoish and AO final polish in my case) don't alter shapes at all so you can use a vibe ( if you want a fast finish) or a rotary, which I prefer, for that final mirror finish. As many have mentioned, for proper prepolish and polish you need lots of tiny rocks in the mix with a much smaller number of cabs. I prefer a mix of tiny rounded and polished agates and jaspers with an equal amount of plastic pellets in the two final runs in the rotary.....Mel
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rockdewd
has rocks in the head
Member since October 2007
Posts: 605
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Post by rockdewd on Oct 29, 2009 11:33:40 GMT -5
I tumble finish 100's of cabs a year. These are the jaspers, pet wood, agates, etc. The expensive or soft stuff still gets hand finished.
Here's my recipe which is similar to Randy's vibe tumbler recipe.
- grind on a 60 grit diamond and finish on a 280 flex wheel.
- then into the vibe with 120/220 for 24 hours. wash out
- another 24 hours with 120/220. wash out
- 600 grit for 48 hours. wash out
- 1000 grit for 48 hours. wash out
- micro alumina or tin oxide for 1 week.
I'm not understanding the issue of "maintaining the girdle" on the stone for bezel settings. I've been a silversmith since 1975. I cut my stones like I would want to set them. I prefer setting stones without a "girdle". Just push the bezel with a bezel rocker into the stone starting at 12 o'clock, 6 o'clock, 3 o'clock, then 9 o'clock. Then work the bezel in between being careful not to move too much metal at once and create a crease in the bezel. Then burnish it smooth with a burnisher. You can also polish up your bezel after setting with rubber wheels that contain abrasives. I use 600 grit then polish on the buffer. If it's a stone that won't stand up to the heat of the buffer then I use 1200 grit wheel then a pumice wheel.
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 29, 2009 22:15:24 GMT -5
Again Thanks for the good input!
Hi there Rick! On the subject of girdles, I wasn't overly clear. I just meant that cabs, being somewhat thinner at the "girdle" edges, might loose a lot of material out there, before you got the dome tops and flat bottoms sanded smooth. I am mainly concerned about loosing that good flat bottom for the stone seat..
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rockdewd
has rocks in the head
Member since October 2007
Posts: 605
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Post by rockdewd on Oct 30, 2009 10:42:41 GMT -5
As long as you don't overdo the vibe tumbling your cabs should stay the same shape as you put them in with a little rounding where the dome meets the back of the cab. If the cabs are getting dished (indented) in the back or the rounding of where the dome and back meet (girdle?) then you are overdoing the vibe tumbling. I see this in Chinese cut cabs all the time and I don't like working with them either.
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 30, 2009 13:24:30 GMT -5
Howdy all! I cleaned out the vibe today, washed and sorted all the media stones, and removed all sharpies, and stuff that needs more grind. I washed the partly broke down grit, and returned it with a bit of fresh 60-90. The preforms went in at a rate of 5parts smooth fillerstone- to- 1 part 280g preforms. I'll check the preforms every day, and remove them as they seem ready for stage 2 sanding, replacing them with more preforms. Meanwhile, I want to order up an extra ultravibe bowl or two. This one will have to remain a first grind bowl, I dont like the drain spout in the bottom of it anyway. that just seems like a bad idea from the get-go. I have the drain filled with caulking, but that doesn't prevent a bit of the coarse grit from working in down there. LOL
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Sabre52
Cave Dweller
Me and my gal, Rosie
Member since August 2005
Posts: 20,497
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Post by Sabre52 on Oct 30, 2009 15:39:27 GMT -5
Julie: Just my humble opinion but I'd not start the cabs in the vibe with 60/90. It might alter the shapes too much. 110/220 should be fine to start ......Mel
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 30, 2009 19:30:27 GMT -5
Thanks Mel,
I will keep an eye on it!!! My main problem is that I only have the 60-90 right now....
I will go order some fresh grit this evening!! Kingsley North, I suppose...
Thomas
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 30, 2009 20:40:31 GMT -5
Here is some of the preform cabs that I will select from to go into my first tumblevibe batch:    Im selecting some of my less-favorites from among a bowl full of these preforms. Im trying to stick to fairly well healed jaspers, agates, and jasp-agates, leaving the oddballs and precious looking ones for finishing out on the genie... |
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 31, 2009 14:23:34 GMT -5
ARRGH! Lesson learned. dont put your good preforms in 60-90, Its way to agressive. I want to remove the morrisonite cabs too, esp the ones with an artistic ammount of host rock remaining around the edges. Sheesh...
Im doing a rock scrub right now with laundry soap, rotten-stone and baking soda, in a pretty wet slurry inside the tumble-vibe. Ive got a coupla ounces of graded 220g and I'll go back at it with that, in an hour or so, after I sort out the destroyed cabs from the happy ones. I did get nice rounding and smoothing on the backs of those preforms that survived tho.
I really should have heeded Randy and Mel's advise.
Thomas "Cab-wrecker" Clark
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 31, 2009 18:34:27 GMT -5
Here's a quick video of the TV-10 starting up with 220g graded, after I removed the damaged cabs. I think this is going to be an expensive batch, I accidently used diamond grit, from my faceting lap supplies. 6-7 tablespoons worth. Should be interesting....  |
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julietom
having dreams about rocks
Member since October 2009
Posts: 57
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Post by julietom on Oct 31, 2009 18:38:20 GMT -5
OK, here's the 220g diamond slurry after about 2 hours, Id say it's cutting pretty dang fast.....  |
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