Question - Is a rock ever really done?

[RWA3006]

Apr 10, 2019 18:20:16 GMT -5 jimaz said:

I think it’s this one:
forum.rocktumblinghobby.com/thread/79231/cuts-mohs-7-agate-butter

Yes, that's it. My findings mirror what James said and I can't imagine not having one of these rigs for lapidary work. It's awesome.

[Wooferhound]

Sounds like you could speed up your Stage 1 a little bit too.
Fill the barrel 3/4 full, Use 80 grit for a 3 pound and 30 grit for a 6 pound tumbler. Fill the barrel with water to half the height of the rocks, you may not be able to see the water at all under the stones.
This will make thick slurry quickly, so listen occasionally and make sure things are rolling properly.

[Rockindad]

Apr 21, 2019 8:57:27 GMT -5 Wooferhound said:

Sounds like you could speed up your Stage 1 a little bit too.
Fill the barrel 3/4 full, Use 80 grit for a 3 pound and 30 grit for a 6 pound tumbler. Fill the barrel with water to half the height of the rocks, you may not be able to see the water at all under the stones.
This will make thick slurry quickly, so listen occasionally and make sure things are rolling properly.

I especially agree about the water. We have seen much better/faster/efficient results with cutting back the water a bit. 

Al

[rockpickerforever]

Apr 21, 2019 8:57:27 GMT -5 Wooferhound said:

Fill the barrel with water to half the height of the rocks, you may not be able to see the water at all under the stones.

This is so true!  In my experience, if you can see the water when the barrel is level, it is too full.  Tip the barrel slightly as you are adding the water so you can see that it is below the top of the rocks a bit.  Or, overfill it, then dump some out.

This will make thick slurry quickly, so listen occasionally and make sure things are rolling properly.

Good observation is key. It's not rocket science, but you do need to pay attention. Keep notes, so when you have a really great batch, you can replicate it. Of course, in order for that to happen, all your variables need to be duplicated, including hardness of rocks, size of rocks, etc., and the rest of the recipe.

But you need to keep in mind it is supposed to be fun, not work.

Just to throw this out there - some of us keep adding grit every few days throughout a tumble, adding sharp SiC to that which is broken down. There are no hard and fast rules on that, you test the waters, learn as you go.

[rmf]

NevadaBill You have to keep in mind that there are different grades of rock facet grade, cab grade and then tumbling grade. Usually Tumbling grade is the lowest end material except for specimen/flower garden grade. There is also too good the throw away but not good enough to keep grade followed closely by leverite. That said the best advice I ever received is to tumble in rough until they are as rounded as you like. When I was doing most of my tumbling I liked really rounded stones so I added more grit and tumbled then in a rotary barrel for a month. Then I moved on to the finer grits in a vib tumbler. this gave me the best compromise between my impatience and the need to monetize what I tumbled. Tumbled stones usually have imperfections and it is a good thing you only want to keep 1%. That gives you the other 99% to sell or give away so you still have room to store rocks. If you are looking for the best tumbled stones upgrade to cabbing rough that has less cracks. Of course it costs more.

[NevadaBill]

Apr 21, 2019 8:57:27 GMT -5 Wooferhound said:

Sounds like you could speed up your Stage 1 a little bit too.
Fill the barrel 3/4 full, Use 80 grit for a 3 pound and 30 grit for a 6 pound tumbler. Fill the barrel with water to half the height of the rocks, you may not be able to see the water at all under the stones.
This will make thick slurry quickly, so listen occasionally and make sure things are rolling properly.

Thank you.  This is a solid tip.  I have been gradually lowering my water levels over the past month, and noticing that there is a thicker slurry much of the time.  The tumbler runs more silently also.

Even though I have only been brave enough to go about 1" below the top rocks on the 12 lb. tumbler and 1/2" below on the 6 lb. it sounds intriguing to me that you have had success when using even far less water than that.  I will have to try this next time.

[NevadaBill]

Apr 21, 2019 9:44:31 GMT -5 rockpickerforever said:

Apr 21, 2019 8:57:27 GMT -5 Wooferhound said:

Just to throw this out there - some of us keep adding grit every few days throughout a tumble, adding sharp SiC to that which is broken down. There are no hard and fast rules on that, you test the waters, learn as you go.

Thank you.   I have a question rockpickerforever .  Do you believe that by combining additional new SiC grit with the amount that is already there would ultimately cushion the load too much?  Thus retarding the shaping and reduction of a load?

Also I wonder about the 3/4 full comment from others above.  I have found that even going slightly above 3/4 full barrel will cut shaping and reduction almost in half for a week of Stage1 in the barrel.  

Obviously this is rock hardness dependent, but I've found the sweet spot to be ideally somewhere between 2/3 and 3/4 full.  Whatever that fraction might be ( 17/24's or so ).

Then again I haven't been tumbling very long now.

I appreciate your input.

[Wooferhound]

Apr 21, 2019 18:23:26 GMT -5 NevadaBill said:

Apr 21, 2019 9:44:31 GMT -5 rockpickerforever said:

Just to throw this out there - some of us keep adding grit every few days throughout a tumble, adding sharp SiC to that which is broken down. There are no hard and fast rules on that, you test the waters, learn as you go.

Thank you.   I have a question rockpickerforever .  Do you believe that by combining additional new SiC grit with the amount that is already there would ultimately cushion the load too much?  Thus retarding the shaping and reduction of a load?

Also I wonder about the 3/4 full comment from others above.  I have found that even going slightly above 3/4 full barrel will cut shaping and reduction almost in half for a week of Stage1 in the barrel.  

Obviously this is rock hardness dependent, but I've found the sweet spot to be ideally somewhere between 2/3 and 3/4 full.  Whatever that fraction might be ( 17/24's or so ).

Then again I haven't been tumbling very long now.

I appreciate your input.

The key is, 3/4 full of rocks -and- water at half the height of the rocks. This will reduce the rocks into slurry very quickly. the barrel will not be 3/4 full after a week.

[NevadaBill]

Apr 21, 2019 10:43:56 GMT -5 rmf said:

NevadaBill ... That said the best advice I ever received is to tumble in rough until they are as rounded as you like. When I was doing most of my tumbling I liked really rounded stones so I added more grit and tumbled then in a rotary barrel for a month...

Thanks rmf.  I think the word "round" is a probably a very good baseline to use as a primary filter, before passing any rocks to Stage2.  I have recently decided to adopt that more.

I am suffering from what could best be described as "acute post Stage 1 depression" most weeks.  Haha.

The rocks that are round, have a pit or spall.  The rocks that are funny shapes are nice (to me), but others do not pick those ones up first.  The round rocks are picked up first by others.  So I think round is important.  But I have some material that just doesn't want to be "round".  They want to be oblong or flat.  Hehe.  

I've got to try to keep a good sense of humor about this.  

[NevadaBill]

All right Wooferhound. I've got all Stage1 coming up in the next couple days. I am going to give it a shot! I am using 46/70 SiC now. I am excited to see what kinds of results I can get. Thank you!

[Wooferhound]

Apr 21, 2019 18:40:51 GMT -5 NevadaBill said:

All right Wooferhound . I've got all Stage1 coming up in the next couple days. I am going to give it a shot! I am using 46/70 SiC now. I am excited to see what kinds of results I can get. Thank you!

Make sure there is some room for the rock to Slide Downhill while it's rolling.

And I have a 6 pound Stage 1 barrel rolling that was started Wednesday using the method I described.

Using some Counter Top material this time, so I'm not sure what to expect. Pretty sure it's manmade stuff. Even have a 'before' picture of that batch.

[Wooferhound]

Yesterday was Cleanout day and I took pictures from the barrel that was loaded 3/4 full and water up to half the height of the rocks for the stage 1 tumble.

This is how the countertop material looked after I broke it up with a chisel and is what was loaded into the barrel

When the 6 pound barrel was opened I was surprised that the water was foamed up to the top

Dumped the countertop material into the colander and the slurry was thinner than I am used to when tumbling rocks with this method. It had been running for 7 days with 3/4 cup 30 grit SiC

Rounded off fairly good and reduced a lot from the start last week

Here is the material placed back in the tumbler after it was washed off. You can see that the barrel is only half full now, when last week it started out at 3/4 full, or as high as the drying-line near the top

[Wooferhound]

When I tumble Rocks using the low water method, I am looking for slurry like this when the barrel is opened.

There are a few raindrop craters in there.