2 Piece Turned Bowl - #6 Glue-up & Finishing

Now that the test piece is finished including the sidetrack it took me on I can take what was learned, apply it and proceed with the actual project.  For the last couple of weeks, the top and bottom halves had just been setting and now it’s time to glue them together. 

The small jaws on the scroll chuck are swapped out for the large ones, the bottom half is clamped in place, the turned cone is screwed on the live center and the top half is set in place.  Dry-fitting is next so I put on a bunch of clamps then took a close look at the joint to make sure the mating faces on both halves lined up good and tight with no gaps.  Fortunately, everything looked good so I unclamped and took off the top then ran a bead of glue on the top mating face, set it in place and clamped the assembly up.  The photo below proves that you can never have too many clamps.

After an overnight curing of the glue the clamps came off the lathe turned on and the joint where the two halved came together was trued up.  For the application of the turquoise inlay I cut a 1/8” x 1/8” groove centered on the joint undercut like in the test piece.  In the photo you can just see a light pencil line near the edge of the outer top face.  That’s a reference line for where my planned finished edge between the outer face and the top will end up.  Right now, it’s a sharp corner but plan on it being made into a nice soft transition to the top surface.

The weighing of the inlay is next.  In the photo below all the necessary items are set out.  The digital scale is the one we use in the kitchen and I have to be very careful using here in the shop since if I get it all messed up my wife will not be happy.

Mixing and application of the inlay material follows the same method as used on the test piece.  The one change is that because it took quite a bit longer to pack the material in I did not have a problem with the mix wanting to ooze out.  Once in place I let it set overnight to cure and the result is this.

After some turning to clean and true up the surface the turquoise band really shows up.  The outer edges are still sharp but the pencil lines show roughly where I plan on narrowing the edge down and then making the soft transition mentioned above.

Turning to round and blending in the edges followed by sanding completes the woodworking phase.  To start the finishing process the body is final sanded to 400 grit while the inlay is sanded finer using an 800-grit paper.  I want to get a sheen on it so used the very fine paper.

The finishing is the same, an application of dye dissolved in alcohol then a coat of lacquer to act as a seal.  Here are both sides done.  Nice thing about lacquer is I can spray the bottom then come back in an hour, flip the piece and give the top its seal coat.

I let the lacquer cure overnight then lightly wet sand with an 1,800 grit foam pad and wipe dry.  This is followed by the application of the gel stain making sure I rub it into the pores.  The photo below shows the effect on the left side.  It acts like a glaze that changes the overall color a little but being a gel packs into the wood’s pores and really makes them stand out.  After this photo was taken, I did buff the piece some with a clean soft cloth which removed a bit of the glaze and color from the body but left the pores dark.

The next day I could spray on a couple of coats of lacquer then let it harden for two more days and finally rub it out with a wet 12,000 grit foam pad.  My final result is shown below a rather simple soft elliptical shape highlighted by the turquoise band around the perimeter.

In looking at both pieces, the test and the final I find that the more I look at them the more the test piece appeals to me.  Maybe it’s because of the finial on the top which gives it a little more visual interest.  I’m not sure, perhaps after I look at them longer I’ll decide to add a finial to the big piece.  If so, I will update the blog when I do.  If you have an opinion one way or another please let me know.

2 Piece Turned Bowl - #5 Testing a Turquoise Inlay

As mentioned earlier I was considering adding a band of turquoise inlay around the center where the two halves join.  It seems like a good idea but there are times that what seems like a good idea isn’t.  To hedge my bets a sample piece sounded like a good way to go.  Taking a small leftover piece of the oak I turned a disk similar in shape but at a much smaller scale and added a narrow groove.  You can’t see it in the photo but the groove is undercut.  By that I mean the sides are tapered so the bottom is wider than the opening.  Just a little extra insurance to form a wedge to better hold the material in place.

The inlay isn’t really turquoise laid into the groove but is a synthetic set in what I believe is a polyester resin.  I started by giving the groove a good blast of compressed air to make sure it was clean.  Next is to weigh out ½ an ounce or because I was using a metric scale, 14 grams of the matrix, add 8 drops of the harder and mix well.  The consistency ended up about like applesauce almost thick enough to hold its shape but not quite.  Using the wooden stirrer, I packed the material into the groove turning the lathe a little at a time working my way around the piece. 

Unfortunately, the material was not quite thick enough to stay in the groove and it slowly started ooze out the bottom.   The good news is that the working time of the mix is not very long so I spent the next 10 minutes or so slowly turning the lathe by hand until the material had setup to a point where it would hold its shape.

After giving the material a full day to cure it was time to try my hand at turning it.  Since I was not sure how it would work first was to sharpen the lathe tool, crank the lathe speed up to about 1,200 RPM’s then using a light touch begin turning the excess away.  Surprisingly it turned very easily and smoothly.  When done removing the excess material I was left with a seamless turquoise band the shape of the groove with sharply defined edges and no staining of the oak.  Last is to sand the piece up through 320 grit except for the turquoise band.  For it the final grit is 800.

The next step is to duplicate the finish used on the actual piece; dye in alcohol, a coat of lacquer to seal, and the gel stain to fill the pores.  The impact on the turquoise band is slight I believe mostly due to the slight amber color of the lacquer.  Here it is ready for the final coats of lacquer.  I am happy with how it looks and will probably go ahead and do a similar banding on the actual project.

As I was about ready to put the lacquer top-coat on it seemed like a waste to just throw it away when done with the test.  A little thought and some doodling led me to decide to try to add a finial to the top and a base that would fit into the test piece mounting hole at its bottom.

The finial is the first piece to be turned starting with a roughly ¾” square by 5 ½” long piece of cherry.  Why cherry rather than oak?  Well, because I want the finial to be pretty thin and delicate, I needed a finer grain wood than oak.  Here it is pretty much done except for the final work on the tip at the right and being cut off at the base of the tenon on the left.  While it does not show up in the photo the base is undercut so it conforms to the curve of the top of the test piece.

I needed a ¼” hole centered in the test piece to glue the finial in.  That’s accomplished by remounting the test piece back on the small jaws which lets me easily drill a centered hole in-line with the test piece’s center axis.

Next is the base.  A small piece rough cut to a circle is mounted between centers then turned round.  Once round the chuck with the small jaws is mounted on the lathe.  What you see in the photo is the tenon that will fit in the hole in the bottom of the test piece.  That hole was for the small chuck jaws to expand into and hold the piece in place.  Again, the first step down is undercut so there will not be a gap between the base and the test piece when it is glued in.

This photo shows the tenon fitted and ready to start working on the transition to the flared part of the base.

When the transition is pretty well done the base is removed from the chuck, flipped end for end and the chuck jaws use the newly turned tenon to hold it.  Now the bottom can be turned getting rid of the drive spur marks leaving a nice smooth bottom.

Because there is a fairly small space where the base and the test piece come together, I decided to finish them separately before assembly.  Here they up on stands ready to be sprayed.  I put them on stands to get them off the cardboard which helps minimize getting any dust kicked up by the overspray.  The blue tape will keep the lacquer off providing raw wood for gluing.

After the lacquer cured overnight the base and the finial gets glued on.  Later that day the top half of the test piece and the finial get a couple coats of lacquer.  I know that I went off on a tangent in what was supposed to be a simple test of the inlay material and method.  Nevertheless, since I don’t have to make a living at this, I can follow wherever the project leads me.  Besides, I like way this little piece turned out.

Next up – Glue-up & Finishing