birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 17, 2004 2:18:35 GMT -5
I just read that un-graded grit will break down much faster than graded grit--Seems that the different sizes in un-graded have their oun dynamic with each other, as well as, with the stones--Graded grit interact much slower with each other-Since i run a 25 day(without recharging) first stage-It is better to use graded 60-At the small price difference I cannot understand why everyone doesn't use graded.
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Post by connrock on Sept 17, 2004 9:43:59 GMT -5
I use graded #30 in rotary tumblers and it does work better then the ungraded 30/60 I tried some years ago. It seems to me that the idea of roughing with #60/90 grit is something that started years ago and has just carried on with time because it is a tad less expensive then the graded #60 you spoke of. I've had some thoughts about calculating the ratio of using graded V ungraded and electric power usage.I gave up the idea because too many factors enter into the equation.What if you can't tend to your tumbler(s) as sceduled?Is your "tumbling recipe" exact in weight and volume every time?Are the belts and or rollers slipping?Are the shaft bearings lubricated the same (friction loss)? etc,etc. I'd say,all in all,if I had to get that "critical" about the cost of my tumbling "habbit" I'd better get into another hobby. I am however doing a comparison study of grit from different manufacturers. What prompted this was the last order of #30 grit I bought from the Graves Co.I noticed it wasn't "cutting" as fast as it should so I looked at it through a 30x jewlers loupe and found that the grit had a filler in it.I don't know what the filler actually is but it "seems" to be a soft "wood like" or "cardboard" material.It would be very hard,if not impossible, to detect visually if it were the same color as the grit. We often mention where we can buy our equipment and supplies at a lower price but sometimes we're only cheating ourselves.I thought the Graves people gave me a good deal!! I don't think putting our grit under a microscope or calculating electric power usage is the answer,,,,,,,,,,,, It's the people who manufacture it that need to be looked at more closely,,,,,, Tom
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 17, 2004 12:39:32 GMT -5
TOM---I agree.....I have seen filler in some grits....
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HarryB41
has rocks in the head
Member since September 2004
Posts: 605
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Post by HarryB41 on Sept 17, 2004 13:04:23 GMT -5
I use graded grits so that I can be more sure of an outcome. With the mix grits I am always afraid that it may have more of one sixe than the others or visa versa. I always start my tumbles with a 60 graded grit. I am learning as much as I can as far as a good polish goes.... I have tried several and I feel like I get about the same results in the end. A friend at a nearby rock shop told me of a guy that started with a 60 SC grit and let it run for about 6 months without changing anything and you could not tell the difference in the ones that went through the 4 and 5 step process and the ones that went 6 months. The shine was the same. To kepp this short........
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deepsouth
fully equipped rock polisher
He who rocks last rocks best
Member since January 2004
Posts: 1,256
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Post by deepsouth on Sept 17, 2004 21:54:40 GMT -5
Hmm , interesting talk here. I Have read in one of the forums that the grit gets finer as time goes by, so why change to a finer grit ? Harry puts it very clear here, 6 month in the one grit without changing. Were there any rocks left Harry ?
We would need a lot more barrels to be able to get through all our mountains of rock we have gathered over time.
What next? no polish needed , just grit?
Jack
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WarrenA
fully equipped rock polisher
Member since November 2003
Posts: 1,530
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Post by WarrenA on Sept 17, 2004 22:50:37 GMT -5
I have heard of the 6 month no change the grit deal but have not tried it as yet maybe when I am finished with my garage construction and get things back in order I can't find half of my rock right now. I can comment on how much more noise that my 15 lb thumler barrel makes over the 6 lb lortone. right now I think I need to change the grit as I am not hearing as much racket as when I first started this batch 3 weeks ago
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 18, 2004 2:51:33 GMT -5
I firmly believe that: 1. 25 days in 60 grit(graded) -no recharge 2. 7 days in 1000 3. 7 days in TXP Sounds like you can make up the price difference, and more, between graded and ungraded grit by not using all the other stages...Is there something I am not understranding here???
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Post by connrock on Sept 18, 2004 7:31:36 GMT -5
Hi bird, As I said before,,I do think there is 1 flaw in this method. The roughing stage IS the most important stage in rock tumbling and with this method I don't see how the rocks will be roughed in properly. Grit breakes down to 1/2 it's size every 7-10 days. For arguments sake let's say if you start with #60 in just 7 days you're already down to #120,and so on until after the full 25 days you will have a grit that is equal to about a #360. Now lets say you start with #60 and run for the same 25 days but recharge every 7 days.With this method you have "roughed" your rocks to a point where they are nicely formed and hopefully have gotten rid of any flaws. It's sort of like restoring an old car. If you don't get rid of the dents and rust before you paint it all you will end up with is a beautifully painted car with dents and rust showing through. Tom
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Post by connrock on Sept 18, 2004 7:46:23 GMT -5
Harry & deep,,, I have a piece of jasper that is about 2-1/2 inches square and maybe 3/4 - 1 inch thick. I roughed it in a rotary using #30 grit and when it was ready for the #120 I added it to a load in a vibe unit. (a vibe unit will break down the grit size in 1/2 every 12 hrs or so) I let it run without a grit change and adding water as needed for 6 days. I was very surprised at the results.The jasper,and the other rocks (montana agate) came out as good if not better then after a pre-polish in Tripoli. If I have time I'll take some pix today. Tom
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 18, 2004 14:45:48 GMT -5
TOM You have a great point--but-even with the 1/2 breakdown every 7 days -I believe 220 does not break down--the stones(if properly prepped-remove all vugs and fractures) will be well formed after 25 days...Give it a try--Also try burnishing your stones in beer...Very good......
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 19, 2004 3:03:49 GMT -5
I just learned that 220 does break down but at a much slower rate..On a 25 day straight tumble the rocks would go from 60 to 220 at the finest--Still lots of abrasive to form and smooth the rocks--and at much less cost---
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Post by rockyraccoon on Sept 19, 2004 11:42:59 GMT -5
birdseed i noticed you said you prep your rocks. this might work for rocks that have been shaped and smoothed. i don't prep my rocks. just chunk 'em in and let the tumbler have at it. sometimes they would probably benefit from some prep work. maybe when it cools off i can work on that. how long have you been tumbling?
kim
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 19, 2004 13:44:31 GMT -5
HEY KIM I have enjoyed this hobby for 40 years +..I have a lot of time on my hands and I prep-if not over prep all the stones-At first I used to throw away lots of first stage stones-That is too expensive-At the start if a stone looks like it will not come out I as want-it is broken and becomes fill..Stones can be preped with a hammer(for fractures) or trim saw..I also wash all my stones before the first stage(except for jasper) have had a gas problem-a little baking soda also.. You sound like you have lots experience at tumbling-what is your style??
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Post by rockyraccoon on Sept 20, 2004 9:27:45 GMT -5
birdseed i've only been at this since last christmas and still have alot to learn. i still have so much i want to learn and more things i want to buy. and some cool weather with no wasps or mosquitos so i can use my saw would be a big plus. i got stung yesterday just trying to wash my rocks and recharge the barrel. if it doesn't move they nest on it. always such a battle with them. my husband sold his little raggedy hunting truck yesterday and the wasps absolutely poured out of it when they cranked it. 300 wasps in the air was more than my eyeballs could stand and i was sprinting for the house hollering "good luck boys". ;D how they did not get stung is absolutely beyond me. i wasn't bothering anything when i got stung.
kim
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Sept 21, 2004 2:59:51 GMT -5
raggity hunting truck=GOOD wasps=BAD
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birdseed
starting to spend too much on rocks
Member since September 2004
Posts: 167
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Post by birdseed on Oct 10, 2004 3:28:47 GMT -5
Actually grits does not get "finer" it gets "duller"..Grit loses it's "sharpness" as the process goes on...
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1Mark
noticing nice landscape pebbles
Member since November 2004
Posts: 91
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Post by 1Mark on Nov 10, 2004 9:17:33 GMT -5
> Actually grits does not get "finer" it gets "duller"...
Ummm... nope, s.c. grit fractures into finer particles with sharp "edges". A.O. grit tends to fracture into more rounded, duller shapes.
Mark
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