Open Segmented Bowl – Finishing the Bottom, Top & a Problem

Now that the halves were glued together and the segment shaping was almost done I could start working on the top and bottom.  First step is to cut off the mounting block from the bottom and drill a recess about 3/8” deep.  This will be used to mount the piece on a set of expanding jaws attached to the scroll chuck.  I need to be careful of my depth, I don’t want to drill too deep and drill through the bottom leaving a hole where there should be a solid bottom.  That would be a very bad thing.

Drilling the Inset for Mounting on Scroll Chuck

With the mounting recess drilled for the expanding jaws I just had to remove a little bit of material from the bottom of the recess to get rid of the drill’s center point and create a nice curved surface.  The base is 5/8” thick, the recess is just under 3/8” deep so I could cut about 1/8” in and still have more than 1/8” of solid wood.  All good planning however, I had forgotten that when turning the inside of the bowl I also turned a slight, just over 1/8” deep arc on the bottom to provide a smooth transition between the first row of segments and the solid base.   If you subtract all of the drilling and turning numbers from the base thickness you end up with a negative 1/8”.  This is better known as a hole.  Consequently, as I was making nearly the last pass on the bottom I cut through it and now had a hole in the base that was supposed to be solid. 

No tools flew across the room but copious bad words did.  After a bit of venting I went back to the piece and cleaned up the ragged paper thin edges around the hole by enlarging it until I got enough thickness for what was left of the bottom to be durable.  Final result is a 1½” diameter hole where I should have had a solid bottom.  Last was to clean up rough sides the drill left and do some minor sanding.   At this point I don’t know what I am going to do I just know that I am not happy with what I have.  Before I retired I worked with a person who said that there are no problems, just opportunities.   Well, I had one heck of a problem opportunity here so I decided to let it sit and see if I could come up with a solution that I liked. 

Hole Where there Should be a Solid Bottom

Next day, no solution so I changed the jaws on the scroll chuck, flipped the piece around, mounted the bowl and cut off the mounting block from the top.  I then removed the piece from the lathe and set it down so I could look at the general shape.  I needed to see the how it looked setting vertically on a surface.  It does look different than when it’s mounted sideways in the lathe .

Initial Review of Bowl Shape

Putting it back on the lathe I flattened the top edge and ran a live center into the hole I had drilled in the top to help with stability.  If you look carefully at the bottom of
the bowl there is the number 3 penciled in along with a line.  That line is a reference mark set on the centerline of jaw number 3 in the scroll chuck.  The idea being that when I take the bowl off the lathe I can reset it exactly where it came off .  This should help with keeping the bowl aligned.

Here I am looking at the top of the bowl before I started on the final shaping .

After doing some shaping I had what I thought was a pretty good profile so I pulled the piece off to take a look.  Better but still not quite right .

Bowl 90% of Finished Shape

More turning and refinement until I had the top to a point where I was happy .  I just needed to do some final sanding.  If you look back at the original design this is slightly different.  Like I said in the beginning my design is not “final” but will evolve as I work on the piece.

Next is to work on refining the bottom part of the bowl.  This should have been done right after I had finished drilling and cleaning up the inset.  However, that did not go so well and I got distracted at that time never getting back to completing the final shaping of the base.   Now with the bowl mounted in the chuck I don’t have room to get my tools in at the base to do any turning.

The fix is to create a true Rube Goldberg setup by mounting the drill bit I used to drill the recess in a chuck and use that to drive the bowl.  Only problem is that after I cleaned up the drilled recess it is now a little larger than the drill bit and is a sloppy fit.  Wrapping 3 layers of masking tape around the bit took up the slack and solved that problem .  I could now finish the shaping of the bottom part of the bowl.

With the last of the bowl turning done I did some finish sanding and the bowl was ready for me to apply a finish except for that #@!L*% hole in the bottom .

Shaping Completed

Next Up – Various Solutions & The Finish