Post by davidp on Jun 6, 2014 0:02:06 GMT -5
Recently harvested some various pieces of seven mile wash rainbow onyx east of Globe, Az.
Cut it with my slab saw to about 3/16" thickness and then cut tear drop pendants with my trim saw.
Running a test batch in my 1.5lb Lortone tumbler and not having much success.
Since it is a fairly soft stone i started off with 220 grit silicon carbide and lots of plastic pellets.
Unfortunately it appears the different colored bands that give it such a beautiful appearance also vary a lot in hardness.
After 5 days of tumbling in the 220 I checked on them and while the edges had all been softened there was also a lot of excessive wear in different parts of most of the onyx giving it a very uneven appearance.
I'm continuing on with some 400 grit silicon carbide and have removed the plastic pellets as I'm wondering if they are not contributing to the problem. I've replaced them with large ceramic pieces to fill the barrel to 2/3 full.
I originally put the plastic pellets in for cushioning but as it's only a 1.5lb barrel, i'm thinking they may not be necessary.
I'm expecting this batch to end up a total failure but I'm going to try and get it through a full run to see the finished product.
I'm planning on doing another test batch with the plastic pellets removed and start with the 400 grit to see if that helps cut down on the uneven wear.
I'm hoping someone else has experience with rainbow onyx and can give me some advice as I don't want to keep wasting this beautiful stone.
Is this stone only suitable for cabachons?
Thanks in advance for your feedback.
David P
Cut it with my slab saw to about 3/16" thickness and then cut tear drop pendants with my trim saw.
Running a test batch in my 1.5lb Lortone tumbler and not having much success.
Since it is a fairly soft stone i started off with 220 grit silicon carbide and lots of plastic pellets.
Unfortunately it appears the different colored bands that give it such a beautiful appearance also vary a lot in hardness.
After 5 days of tumbling in the 220 I checked on them and while the edges had all been softened there was also a lot of excessive wear in different parts of most of the onyx giving it a very uneven appearance.
I'm continuing on with some 400 grit silicon carbide and have removed the plastic pellets as I'm wondering if they are not contributing to the problem. I've replaced them with large ceramic pieces to fill the barrel to 2/3 full.
I originally put the plastic pellets in for cushioning but as it's only a 1.5lb barrel, i'm thinking they may not be necessary.
I'm expecting this batch to end up a total failure but I'm going to try and get it through a full run to see the finished product.
I'm planning on doing another test batch with the plastic pellets removed and start with the 400 grit to see if that helps cut down on the uneven wear.
I'm hoping someone else has experience with rainbow onyx and can give me some advice as I don't want to keep wasting this beautiful stone.
Is this stone only suitable for cabachons?
Thanks in advance for your feedback.
David P