Post by Jugglerguy on May 15, 2016 15:38:59 GMT -5
I spent several hours yesterday and less time today making one Petoskey stone into three Petoskey stones. That was not the plan. What I attempted to do is copy this guy's creation.
I figured if I used Petoskey stone, there would be a huge contrast between the raw rock and the polished inside. Petoskey is also very soft, so it is fairly easy to shape and polish by hand. What I forgot is that it also breaks pretty easily.
I started by hot gluing the rock to a board and making a jig to cut parallel to the bottom of the rock.
Then it took a lot of trial and error to get the jig into this position to make the next cut.
I cut a piece of sheet metal to protect one side of the cut while I sanded the other side. I wrapped the sandpaper around another piece of sheet metal to get in the groove.
Everything went well here and I finished up yesterday very pleased with the progress I had made. I thought that would be the hardest part. I was wrong.
Today I had to cut the end off the rock and polish it up. I wasn't quite sure how to line the cuts up right. I came up with this. I glued the rock to another board and lined the old cut up with the blade using a ruler.
Blurry picture, but it worked great.
The last cut I couldn't figure out how to do except by hand. I had to sand a lot of this off, so I wasn't too worried about it being perfect. The cut wasn't great, but it would do.
The problem came when I tried to sand the end. I put too much pressure on it and it broke. I had it in my bench vice and was sanding it with a piece of sandpaper wrapped around a piece of PVC pipe. The rock ended up not being great, so I wasn't as upset as I would have been if it had been a beautiful rock. I didn't cry or throw any sort of tantrum.
Here's the end. It was pretty porous. That probably contributed to it's weakness.
It will be difficult to find another rock suitable for this project. Most Petoskey stones are sort of flattened with the pattern on top. It's unusual to find one that is oblong with the pattern on the end. Someday I'll find another and maybe try this again.
I figured if I used Petoskey stone, there would be a huge contrast between the raw rock and the polished inside. Petoskey is also very soft, so it is fairly easy to shape and polish by hand. What I forgot is that it also breaks pretty easily.
I started by hot gluing the rock to a board and making a jig to cut parallel to the bottom of the rock.
Then it took a lot of trial and error to get the jig into this position to make the next cut.
I cut a piece of sheet metal to protect one side of the cut while I sanded the other side. I wrapped the sandpaper around another piece of sheet metal to get in the groove.
Everything went well here and I finished up yesterday very pleased with the progress I had made. I thought that would be the hardest part. I was wrong.
Today I had to cut the end off the rock and polish it up. I wasn't quite sure how to line the cuts up right. I came up with this. I glued the rock to another board and lined the old cut up with the blade using a ruler.
Blurry picture, but it worked great.
The last cut I couldn't figure out how to do except by hand. I had to sand a lot of this off, so I wasn't too worried about it being perfect. The cut wasn't great, but it would do.
The problem came when I tried to sand the end. I put too much pressure on it and it broke. I had it in my bench vice and was sanding it with a piece of sandpaper wrapped around a piece of PVC pipe. The rock ended up not being great, so I wasn't as upset as I would have been if it had been a beautiful rock. I didn't cry or throw any sort of tantrum.
Here's the end. It was pretty porous. That probably contributed to it's weakness.
It will be difficult to find another rock suitable for this project. Most Petoskey stones are sort of flattened with the pattern on top. It's unusual to find one that is oblong with the pattern on the end. Someday I'll find another and maybe try this again.
