Game Piece Holder – #2 Finish Turning Prototype & Different Feature Accents

With the outside of the bowl turned to its final shape it’s time to start on the inside.  This starts by taking the blank out of the lathe and flipping it end for end so the base is now at the headstock end.  I didn’t mention the scored line near the bottom before but that’s where the bottom of the bowl will be.

Marking the bowls ¼” wall thickness is next to give me a starting guide.  Also, a hole is drilled just short of the depth I need to hollow out to.  Since I had the Fostner bit already in the chuck that’s what got used.

Here the bowl is a bit over half turned.  The red arrow points to a pencil line partway down the inside of the bowl.  That’s my reference mark showing from there to the lip of the bowl is the correct thickness with everything on down too thick.  From here it’s removing material and checking the wall thickness along with the depth until done.

Once the interior of the bowl is turned to size it gets sanded then removed from the 4-jaw chuck and the jaws get changed out once again.  This time a set of Jumbo jaws get installed and the bowl gets mounted top edge in.  As the bowl’s walls are only ¼” thick the jaws get lightly tightened down to prevent the walls from being damaged.  To provide some stability the tail stock gets a live center brought up and a little pressure applied to hold the bowl in place.  Now I can clean up most of the base then cut the foot off.

Last is to finish turning and cleaning the base up.  Here on the top left is after the foot was cut off and on the top right is the finished base.  The bottom two images show different views of the bowl.

With an actual mid-size bowl done I measured its real volume which was 1 cup with the calculated volume of .953 cups, close enough for our purposes.   The drawing below shows the comparison between all three different sizes that I will be making.

With the woods selected, the prototype finished along with the overall shape and stepped sizes set it’s time to do some testing of the various types of feature accents we discussed.  Those include the following where each of the items are about ½” or so down from the top of the bowl:

• A copper band around the bowl.
• Six equally spaced round aluminum or brass dots inlayed into the wood.
• Six equally spaced square walnut pegs set into the wood deep enough so that when the bowl is turned, they will be visible on the inside of the bowl.
• A turquoise ban inlayed around the bowl.
• A band of brass shavings inlayed around the bowl set in a clear epoxy.

 Two other possibilities also include a feature similar to what’s at the top but at about ¼” up from the bottom of the bowl.

• A series of three grooves burned into the bowl at the top and one at the bottom.
• A feature ring consisting of three thin wood layers with the top and bottom matching and a contrasting center layer.

Now there were some early tests that got quickly discarded for one reason or another.  One example was the idea to use lead free solder to fill either square or round holes.  The photo below shows that test.  One problem was that the melting point of the solder was pretty close to the burning point of the wood and it ended up charring the edge of the holes.  Also, there was enough surface tension in the molten metal that the square corners didn’t get filled. 

Making a decision on which features to use is next.  During our discussions one was a clear choice, that of the turquoise inlay probably in oak as a nod to where we live in the Southwest.  Beyond that it was pretty open so I started with four promising possibilities.  The copper band, brass and aluminum dots and square walnut pegs.  Taking some scrap oak a block was laminated up and turned to a cylinder using the same process as the cedar prototype giving me a blank canvas to work with.  At this point a major part of the testing was to see if I could actually make what I had designed.  The brass and aluminum inlay dots had me concerned because with the bowl walls a ¼” thick I really only had 1/8” depth to work with.  Laying out the dots was the first problem since they needed to be equally spaced with the mounting hole drilled perpendicular to the center of the cylinder.  In the end this is the setup I used to accomplish that.

Cutting the dots, fastening them securely in place then bringing them flush to the wood turned out to be challenging but doable.  Both the copper band and walnut square inlays were easier than I thought.  The photo below shows the results from this first bit of testing. 

In a video call with my son, we discussed which options might look the best with which woods.  Using photos of three different woods and some time with Photoshop, I put together these possibilities.  More discussion ended up with selecting the copper/walnut for sure.  The burned lines in maple are a strong contender with the square walnut inlay and aluminum dots rejected.

Next alternates for the oak and turquoise were discussed as there were three different color mixes available with a fourth option of contrasting layers thrown in for good measure.  The choice was the top right image. 

Besides the oak choices there were eight others for the maple and cherry.  Those are shown below along with the walnut and copper version we had selected.  The cherry bowl generated the most versions and we ended up with five different possibilities.

I am not going to bore you with the discussions on how the final designs were selected but here are the final four choices.  In a curious twist the aluminum and brass options that were the most difficult to do in testing got eliminated for aesthetic reasons.

The last decision to make was regarding the spacing from the top for the various feature rings.  I thought constant spacing of the top and bottom decorative rings might look out of proportion with the different sized bowls.  To my surprise after doing some drawings the bottom inlay at the same height looked fine while the top inlay did not.  In the drawing the bowls on left have the same spacing while the bowls on the right vary by less than a tenth of an inch.  Not much but it does make a difference since it’s the details that count.

Next Up – Sacrificial Bases, Walnut & Cherry Blanks plus Making Veneer

Game Piece Holder – #1 The Start, Design & Material Selection

This project is going to start with more than the usual amount of background information regarding the design process including 3D drawings, photo renderings and some prototypes so bear with me as I explain how this project unfolded. 

Not too long ago while my wife and I were having a video call with our son I asked him if he had any ideas for a belated Christmas present.  I had asked him if he was interested in me making him something like our end grain cutting board.  He said not really as they already a cutting board that gets limited use, works just fine and might end up as a display piece.  We kicked around some things then he mentioned that as a board gamer he had looked at several different kinds of containers to hold the game’s pieces during play and hadn’t gotten anything yet.  This piqued my interest in that it was something he wanted, would be used and I could make.  We discussed various shapes including triangular, square, hexagon and round with or without a base.  I liked the idea of doing something round that could be turned on a lathe which would allow design freedom along with the ability to use a single form.  It would also allow for the ability to have different types of feature accents and he agreed with the idea.  After those intial discussions I sent him several different shapes and forms of feature accents.

Additional discussion regarding functional design requirements included the holders having gently curved interior sides so pieces are easily removed, wider that tall for same reason, stable, graduated sizes for holding different sized or different quantity of items and stackable to reduce storage requirements.  Here was an early quick 3D drawing used after the general shape had been decided on and the initial size had been increased but not finalized.

As it turned out even our revised size bowl that’s 3 ½” in diameter holding ½ a cup was too small for anything but the smallest size.  Upsizing the other containers we settled on three bowls at 3½”, 4 ¼” and 5” in diameter with proportional heights.  This will also give the ability for them to stack for storage.

By now we had decided that there would be three bowls in a set and four sets for a total of 12 bowls.  At this point I took the mid-sized bowl and did some 3D drawings showing a couple of ways they could be embellished, just to get things going. 

Next is to discuss what the bowls would be made out of as we wanted each of the four sets to be made from a different wood.  I came up with five different possibilities: cherry, oak, maple, walnut (not shown) and leopardwood.  In the end the leopardwood got dropped because that while the figure of the wood is striking it probably would be too much given that we had planned on adding some sort of feature accents to the bowls.  Also, it would have required more pieces glued together to get the size turning blocks needed than I wanted to see.

So far all we have had to work with is flat 2D drawings and some 3D renderings.  To get a better idea of what the actual piece would look and feel like I decided to make a middle size bowl out of cedar.  This is the same material as used to make the prototype of the just completed Wastebasket.  Since the raw piece to be used is rough sawn and has a bit of a twist the blank gets cut into smaller pieces (top photo) then the low corners get shimmed until the blank sets flat (bottom left).  From there it gets run through the thickness sander until the surface is flat and smooth.  The bottom right photo shows this in progress where the high corners have been knocked off.

The top photo shows what a finished piece looks like and the bottom photo shows the layers cut to size and ready to be glued together.

Gluing the pieces into a block is next.  Here the large red clamps hold the stacked pieces in alignment while the grey clamps apply the downward clamping pressure to the glue joints.  I might have used a little bit too much glue on the joints.  After a few minutes to give the glue a chance to “grab” the large red clamps are removed and the excess glue cleaned off.

Next is to make a template for the middle-sized bowl which is the bottom one in the top left drawing.  At the top right is after I cut it out using a jig saw.  The bottom left is the oscillating drum sander ready to begin fine tuning the template.  This drum will take care of most of the cleanup but as I need to get into tighter radiuses the drum gets swapped out with smaller and smaller ones.  The fine cleanup is done with fine files and sandpaper ending up with the template at the right bottom.

After the glue cures overnight, the center is located and an oversized circle is drawn with a compass then cut out using the bandsaw.  Mounting the block in the lathe is next.  First the drive center gets a good whack with a mallet leaving tooth marks in the block which will provide a good grip for turning.

Here the piece has been mounted in the lathe with the drive center on the left and the live center which freely spins around on the right.  Turning the block round to an even diameter cylinder is next.  A nice sharp turning tool generates the wispy shavings shown.  If you are not getting those then the tool is not sharp enough.

To drill a centered mounting hole in the blank I will use my 4-jaw chuck to hold the piece with the center line of the blank aligned with the lathe’s axis.  For various sized pieces I have four different sized jaw sets.  Here three are shown and I will use the largest of them.

In the top photo the blank has been secured in the 4-jaw chuck using the live center to align the center of that face with the lathe’s axis.  The bottom photo shows the live center replaced with a Jacobs chuck and a Fostner bit so a mounting hole can be drilled.  In this method of drilling the blank spins and the bit does not move.

With the mounting hole drilled the blank is removed, the chuck’s jaws get swapped out for the smallest set, the blank reversed with the newly drilled hole mounted over the jaws.  They are then expanded to hold the blank in place and the exterior can be turned to shape.  This photo shows the blank rough turned.

Turning continues until the blank fits in the template.  Part way through I found that a half template worked a lot better than a full one.  After going through making the prototype I also found that swapping the chuck’s jaws is not the fastest method to set up the mounting since swapping out the jaws takes some time.  With 12 of these to turn I want to streamline the process where possible.  When I get to the actual bowls I will go through the revised mounting process.

Next Up – Finish Turning Prototype & Different Feature Accents