Segmented Bowl – # 12 Gluing Halves, Final Shaping & Finish Selection

With the interior shaping and finish sanding 95% done the last bit of work to do before gluing the two halves together is to apply tape inside the bowl at the glue joint.  This is to keep any glue runs on the inside from adhering to the area adjacent to the glue joint. This makes cleanup and blending the inside joint a lot easier.

With that done the glue is applied to the top half’s joint, it’s set in place, the alignment of the two layers set and the two halves are clamped together using the tailstock to apply pressure.  Since another set of hands are needed my wife tightened the tailstock while I held the top half in place.  The little glue squeeze out on the outside gets cleaned off and the assembly is left for the glue to cure overnight.  The red arrow in the bottom photo points to the top/bottom joint.

The next day the tape gets removed from the inside which worked very well with only a little ridge of glue to be removed.  No photo of that since I can’t figure out a way to get the camera inside the bowl to take one.  What’s shown below is the bowl removed from the lathe and stood upright so the shape could be critiqued to see what refinements need to be done since that can’t really be done horizontally in the lathe.  To my eye there are four places that need some work.

1. The shoulder’s radius is too small so I need to bring this point in to soften the transition between the top and the feature band.
2. Here the top of the just completed joint is just slightly larger than the layer below.  This and the shoulder being oversize were planned to give me extra material to blend both together for a good flow up from the feature band.
3. It’s almost impossible to see here but there is a slight swell at this point that breaks the smooth curve down to the base.  However, when running my fingertips across the surface it certainly can be felt.
4. The base is too wide and needs refinement.  This too was planned because I wanted to keep it as wide a possible for stability while turning.  If it is too small then the piece is not rigid enough when turning and you can get vibration out at the end and that causes all kinds of problems.  This will be the last area addressed once all the others are done and the piece is sanded.

Here is the finished turned and sanded bowl except for the bottom ¾” or so.  That will be done later.  The bowl is now ready to be put back in the lathe and parted off the base.  This follows the same process as parting off the top done earlier.  Once cut off the base needs to be cleaned up but before that can be done an adapter has to be made to go between the base and the tailstock of the lathe.

The adapter starts with a cylinder just over 2” in diameter then has the right end turned down to 2” shown in the top photo.  This smaller end will fit in the recess under the oak plywood inset base that was put in early on.  The red arrows in the bottom photo from early on in the project shows the plywood and the recess it will go into.

The other end of the adapter gets a hole drilled in it which is then tapped adding threads (top photo) so it can be screwed onto the live center in the tail stock.  The bottom photo shows the threaded adapter and the threaded end of the live center where it will go.

Here the bowl is mounted back in the lathe with the adapter in place.  As the adapter is sized to just fit in the recess it holds and centers the bowl so I can clean up the last little bit of the bottom of the bowl.

The top of the bowl fits over the tenon on the faceplate/mounting block assembly and has a paper towel to take up slack and cushion the edge of the top since it has been finish sanded.

In the photos below the adapter is in place in the bottom of the bowl and you can see how it just fits in the recess.  The left photo is what the bottom looked like after it was cut off the mounting block while the right photo shows what it looks like after it’s cleaned up and sanded.  At this point the woodworking part of the bowl is done and I am ready for the finishing to begin.

However, before the finishing can begin cleanup needs to be done in the shop to reduce the amount of dust in the air since it seems like a wet finish attracts dust like a magnet.  The first place to start is at the lathe.  Now early on I did clean up around the lathe each day but got lazy and decided to wait until the turning was all done.  As you can see there are a couple of pretty good-sized piles of shavings plus one more behind the lathe that you can’t see.  All told just around the lathe there was enough to fill a couple of garbage bags.

Once the shop is cleaned up, the application of the finish can start.  In an earlier post I mentioned that I would use a Wipe-On polyurethane rather than my usual sprayed lacquer finish.  Spraying a lacquer finish on the outside of the bowl is easy as it’s no problem to get to all the outer surfaces.  That’s not so with the inside as there is no way I can get the spray gun inside the bowl and using a brush won’t work. 

That left me with a few wipe-on finishes like Danish Oil Finish, boiled linseed oil or a wiping varnish.  Of those I like Danish Oil Finish or a wiping varnish like Wipe-On polyurethane.  In general, I use Danish Oil Finish when the piece can have a rough life and will probably need the finish refreshed sometime in the future.  An example is tool handles or toys that kids will play with neither of which applies here.  I also want to have the option to control the amount of shine the final surface will have and with Danish Oil Finish it’s usually a matt finish.  All this led me to using Wipe-On polyurethane.

Next Up – Finishing & Wood Leftovers