frostedoddity
off to a rocking start
Hello from Tampa Bay, Florida!
Member since May 2017
Posts: 8
|
Post by frostedoddity on Jun 8, 2017 17:59:05 GMT -5
I have a Thumler's Tumbler with a 15 pound barrel that moves pretty fast. When I pay money for material, or tumble something workable I found that's a little rarer than usual, I occasionally worry about the material being damaged or wearing away, and this makes me want to check on even material with a hardness of 6.5-7 every three days in the rough grit stage (currently using 60/90). I'm also concerned about tiny internal cracks (bruises) that happen from impact. How often does breakage and impact damage still occur if the tumbler is filled with plenty of ceramic media and plastic pellets? Also how much rock can you expect to lose from start to finish with a rough piece? I heard it's somewhere around 30%. Can very small material be mixed with regular/large? I feel like, unless checked on and separated soon, the very small stuff will wear away before the regular/large sized stuff is ready.
Also, for very round stones I'm guessing the perfect rough is roughly square or rectangular in shape and solid throughout, free of crack and pockets? Does anyone tumble and polish rocks with the intention of retaining some of their original shape? If I have a piece that's thin and long, or oblong, I feel that some of the shape would need to be retained or else it's going to end up at least 1/3 of its original size.
Basically I just want to be able to tell the difference between my mistakes and what's unpreventable. I feel like I have a responsibility to bring out the best in what the Earth made. I want to tumble to create, not destroy.
|
|
doublet83
starting to spend too much on rocks
Member since March 2016
Posts: 118
|
Post by doublet83 on Jun 8, 2017 20:04:43 GMT -5
I usually end up removing 40 to 50% of the material to get it to a nice shape that I'm happy with. But you should experiment and do what you like.
Its good to mix small material with large. The small material will wear down a bit faster.
I have the same tumbler, and don't use any ceramics. Never had any issues with bruising on 7 hardness material.
|
|
Fossilman
Cave Dweller
Member since January 2009
Posts: 20,687
|
Post by Fossilman on Jun 9, 2017 8:32:21 GMT -5
Sounds like you should invest in a smaller tumbler too..For those delicate materials you speak of....
|
|
frostedoddity
off to a rocking start
Hello from Tampa Bay, Florida!
Member since May 2017
Posts: 8
|
Post by frostedoddity on Jun 9, 2017 12:06:44 GMT -5
Sounds like you should invest in a smaller tumbler too..For those delicate materials you speak of.... I actually do have a slower moving 3 pound Thumlers tumbler that I also use, and have thought about using it to experiment with softer stuff. Although, even that has done some damage. About a decade ago I wore a few nice stones into pebbles and bruised/cracked some agates with it. Or course, I've learned a lot since getting back into it. I was probably mixing a few soft pieces with a lot of hard ones, and I don't even remember if the agate material was that good or if I was using the right ratio of pellets, and I always left it running for a week without checking on it. Just gotta push forward!
|
|
frostedoddity
off to a rocking start
Hello from Tampa Bay, Florida!
Member since May 2017
Posts: 8
|
Post by frostedoddity on Jun 9, 2017 12:19:26 GMT -5
Who's tumbled petrified wood? I'm actually doing a batch mixed with chert and a little granite in my 15 pounder right now. It's one of my favorite materials because some pieces still retain the shape and grain lines of a piece of regular wood, and I actually think it would better compliment these types of pieces to just smooth the edges out a little instead of turning them to round stones. Any opinions on this?
|
|
tkvancil
fully equipped rock polisher
Member since September 2011
Posts: 1,546
|
Post by tkvancil on Jun 10, 2017 8:56:43 GMT -5
Who's tumbled petrified wood? I'm actually doing a batch mixed with chert and a little granite in my 15 pounder right now. It's one of my favorite materials because some pieces still retain the shape and grain lines of a piece of regular wood, and I actually think it would better compliment these types of pieces to just smooth the edges out a little instead of turning them to round stones. Any opinions on this? They are your rocks and you can tumble them as you like. Many of my local finds have fossils in them so if one is really cool I will not tumble past it. Sometimes that means a less than "perfect" rock. Recently finished some Botswana agate .... many had natural vugs / voids ... tumbling them out would of left a small perhaps less attractive rock. So yes "flawed" rocks and natural shapes can certainly be polished. As to the tumbling process damaging rocks ... for the most part this doesn't happen. A lot of rocks, agates in particular, can have fractures when we get them. The tumbling sometimes can aggravate these but generally isn't the cause. Exceptions ... a barrel that has too low a volume can lead to chipping, frosting, etc., so be sure to have the barrel 2/3 to 3/4 full. An overly thick slurry can also cause issues. I once had a slurry get so thick all the smalls stuck to the edge of the barrel. The bigger pieces were crashing around in the void that was left. What a mess. If you want well rounded stones expect to lose about 50%. I'm doing a batch of Crazy Lace. Started with 40 pounds, which is enough to fill four 12# lortone barrels. After 6 weeks everything is pretty well rounded. I'm down to enough rough to fill about two and one half barrels. Have a couple weeks to go on some of them so by the time I'm done after culling and grinding I should have about 20# to finish.
|
|
|
Post by captbob on Jun 10, 2017 9:36:22 GMT -5
If you want well rounded stones expect to lose about 50%. I'm doing a batch of Crazy Lace. Started with 40 pounds, which is enough to fill four 12# lortone barrels. After 6 weeks everything is pretty well rounded. I'm down to enough rough to fill about two and one half barrels. Have a couple weeks to go on some of them so by the time I'm done after culling and grinding I should have about 20# to finish. +1000
|
|