After posting yesterday's blog post, I received several emails with questions about the magnet I used in it, and how well it does or does not work. So today I decided to test it out so I could answer these questions with some kind of honesty instead of simply giving my best guess.
If you clicked on the link I provided to watch the video on constructing the tool (video is here), you know that a sphere shaped magnet is what is called for. That was one of the issues I was asked about. I did not have a sphere shaped magnet. I used a disk shaped one in each of the holes. You can see in the above photo the type magnet I used and what I used to put it in with. I dropped a tiny bit of CA glue in each hole, stuck the magnet on the end of a long nail, and stuck it in the hole. After allowing the glue to set, I simply pulled the nail out.
So I needed a test subject. I had this short section of a cedar log setting in the shop and thought it would make a nice bowl.
By the time I thought to snap another photo, I'd already lost several inches of height on the bowl. I'll talk more on that in a bit. First, how does the sander perform?
I found the roughest area I could find to photograph on the bowl. I knew I could find the same area again because, you can't see it in the photo, but the plates on my chuck have reference numbers for placement, and this area is even with the number four plate.
I sanded with eighty grit paper and set a timer for thirty seconds. As you can see if you look closely, it still needs more sanding, but it is a huge improvement.
So, in my opinion, although I have never used one with the sphere shaped magnet in it, I think this works just fine for what I want.
Sometime in the future, I plan on buying a commercially made version of this tool. If anyone is interested, let me know and I'll post my opinion at that time on how it compares to this shop made one.
Now, back to the cedar bowl. I kept losing height. This is one of the joys, and also drawbacks, to turning. You never know what you're going to find inside a piece of wood until you start turning it. Well, this particular piece of wood had more cracks in it than a three mile stretch of side walk. Every time I got it looking good, a piece would break along a crack somewhere near the rim.
You can see here what I mean.
No big deal. I like to think of headaches such as this one as learning exercises. So what could I learn from this bowl that seems to not want to be completed?
I decided that, with the crack and the brittle nature of very dry cedar, I'd see how thin I could get the walls. That's something I've been working towards is getting the walls of my work thinner.
I got it down to an eighth of an inch and everything was going great. Then the bowl decided that it would like to be shrapnel more than it wanted to be a bowl.
Seriously, a bowl that breaks into many pieces at high RPMs becomes shrapnel.
This is all the pieces I could find of it for the photo.
And THAT, my friends, is why you always, ALWAYS, wear a full face shield while turning.
Of course, I was asking for this one to blow apart. However, you never know when it will happen. In the past, I have had bowls, or parts of bowls, leave the lathe at high speeds when I least expected it.
Until next time, happy turning!