Saturday was our monthly meeting for the Arizona Woodturners Association, and our demonstrator for the day was fellow club member and Creeker Dale Gillaspy. Dale did a great demo on multi axis bowls and other embellishments, and unwittingly showed us how well our new plexiglas shield worked to prevent injuries when the perfectly solid bowl he was working on decided to launch about a 1/4 of the rim directly into the front row (it hit the shield and dropped harmlessly to the floor). So for any clubs that don't currently have a shield to go in front of their lathe, I highly recommend getting one. Ours was made and donated to the club by one of our club members, a simple metal framework (I think the base had wheels) with a sheet of plexiglas hanging from the top.
Now for my Oops.
Dale's process for turning bowls on multi axis (axi?) was straightforward and only required a faceplate, some screws and a 2 x 4, so on the drive home I was planning out the bowl I would turn when I got home.
The first thing I needed was a 2 x 4. I knew I had some 2 x 6 stock laying around and figured I could just rip it down, but when I started going through the boards I found they all had some cracks and a cracked propeller, spinning off balance, just didn't seem like a good idea to me.
So I went to the wood pile, found a half log section of mesquite that was the right size and sound, took it to the bandsaw and made a mesquite 2 x 4. I rounded off the corners for a little bit of extra safety.
Next, I marked the center of the board and also drew a line down the center of the length of the board. Then I took it to the drill press and drilled a small hole at the center point, and more holes every 1/2" for 2" on either side of the center mark.
Then I turned a little centering jig to line up the face plate on each of the centerline holes. Just a spindle about 2" long with a diameter that would slip inside of the threads of the faceplate, with a small hole drilled in the center of one end where I CA'd a small nail with the head ground off.
I placed the jig nail in each of the predrilled holes, slipped the faceplate over it and then marked for the mounting holes. Then back to the drillpress to drill holes for mounting the faceplate at each position along the centerline.
I attached the faceplate to the 2 x 4 at the center position, mounted it on the lathe, and then turned a recess about 1/4" deep with a diameter to fit a typical size tenon that I would use for a smaller bowl. (I color coded the holes for each position to make it easier to line up with the correct holes)
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Now it was time to find a bowl blank. Since this was a new technique for me, I didn't want to waste a "good" blank. I looked through my supply and found a sissoo blank of the right size, which was pretty plain with little heartwood, so I knew it wouldn't bother me if it ended up as firewood.
I mounted it on a screw chuck, then turned a tenon on the bottom that would fit snuggly in the recess in the 2 x 4.
Then I mounted the 2 x 4 on the center position. Since I haven't seen my hot glue gun in years, I used a little medium CA to secure the tenon in the recess. Then I trued up the face of the blank.
Then I unmounted everything and moved the faceplate to a position 1" over from the center. I remounted it and started hollowing the 1st depression. I kept the speed down since it was off center and out of balance. After the 1st depression was turned, I moved the faceplate to the 1" position on the other side of the center and started to turn the 2nd depression and this is where it started to go downhill.
Since my design had the 2 depressions intersecting, when I started turning the 2nd depression the cut was intermittent where it intersected with the 1st depression. Apparently I didn't use enough CA (I wanted it to be secure, but not permanent) and with the rough, intermittent cut as low speed, there was enough bumping that I managed to knock the bowl loose from the recess.
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Oh well, I'd just reglue it and use a little more glue. It wasn't until I started turning it again that I realized that I didn't pay any attention to the orientation of the bowl when I reglued it. So now, depression #2 was going to be next to #1 instead of opposit it. Oh well, another design opportunity.
The reglue held up fine and when I was done with #2, I remounted the faceplate in the center position for #3 and turned the final and largest depression.
The end product was nothing like I had planned and I wasn't happy with it, but I went ahead and finished off the bottom so I could keep it around as a reminder to mark the position that the bowl is attached to the 2 x 4 so it could be reattached at the same position in the event it comes loose.
It wasn't until I uploaded the pics that I realized I could have turned it into a normal bowl just by enlarging depression #3 until #'s 1 and 2 were turned away. Oh well, live and learn.
About 8" x 2", unsanded and unfinished, sitting on the shelf and mocking me
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Maybe my Oops will be of help to anyone wanting to try a multi axis bowl or plate.
I will be trying another, but it will be planned out a little better.
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