Pulling the material out of my stock is next. In the photo below the two short pieces on the left are oak, the two on the top right are 1 7/8” square leopardwood and the large piece on the right along with the long piece at the bottom is 1 7/8” thick cherry.
After measuring the long cherry piece, I thought that there was just enough to get the body out of it, if everything worked just perfectly. The constraint is not the thickness but the width of the individual pieces. The final design diameter is 12” and I want a 12 ¼” diameter blank to give me a 1/8” buffer around the edge, not a lot but enough. To give me the maximum usable material a thin kerf saw blade is used. The left photo below has the thin-kerf blade on the left and a regular kerf blade on the right. Now it’s not a lot thinner but there are seven joints in the blank so every little bit helps. To set the fence for the cut the minimum piece width is marked on the end of the board and the fence set so the body of the blade is centered between those two lines as shown in the right photo. It’s important to use the body of the blade and not one of the teeth since the teeth have a left and right set to them. With a careful centering of the blade body, I can get a matched set of pieces with thickness to a few thousands of an inch of each other.
The long boards now get cut to length using a stop block and the chop saw except for the outer two pieces because they don’t have to be as long as the others. I did not cut them right away because I think there is almost enough to get them from the remainder of one of the long boards. If they get cut from the last two blanks I would end up a couple of short waste pieces. This will make more sense in the next photo. To keep them in sequence the end of each board is lettered and numbered.
To see if the end pieces can be cut from a single piece the remainder of the parts get clamped together and a circle is drawn on them the size required for the blank. I can then measure the length required for the outer pieces which lets me know if one piece is long enough for both or if I will need to cut one from each of the remaining blanks. As it worked out one board cut in half was enough with just a little to spare. The photo below shows the finished clamped dry fit assembly with the short outer pieces.
Gluing the pieces together is next. The top photo shows the pieces turned ¼ so the glue face is up. The short piece near the bottom of the photo is the end piece and won’t need glue since there are eight pieces and seven joints. In the bottom photo the glue has been applied using a fingered rubber glue spreader set in the blue holder at the top. You can see where the glue stops short on the last clamped piece because that’s where the short end piece goes. Here I used a waterproof glue not because it’s waterproof but because the dried color is closer to aged cherry.
Once the glue cures the blank gets run through the thickness sander to flatten it along with cleaning up the top and bottom surfaces so it’s ready to be rough cut to size. 
Cutting a circle a ¼” larger than needed on the band saw is next. Since it had been some time since I checked the squareness of the table to the blade, I took just a minute to do that using my small steel square. The top left photo shows everything was good and square and the top right one is ready to start cutting. The bottom photo has the blank cut round.
Drilling a small hole through the center of the blank using the drill press is next. This will be used for registration when the blank gets reversed during turning. With a small hole dead center, I can use the live center in the tail stock to get the blank’s axis dead on with the lathe’s axis and provide some extra support when turning.
Next is to drill a 2 ½” diameter recess in one face where the four jaw expanding chuck will go to hold the blank in place while turning. The outer pencil line is the outside edge where the inlay will go and the inner line is the where the through hole will eventually go. 
With the mounting hole drilled mounting the blank in the lathe for a squareness test is next. Below you can see a drive center on the left and the live center on the right both inserted into the small through reference hole. In theory because the reference hole is square to the blank and used to align the blank to the lathe’s central axis it should spin smoothly with no wobble. Good plan that didn’t work as well as I thought because when spun the blank wobbled about 3/32” side to side and that’s too much. 
To rectify getting the blank square with the lathe’s axis is first. That can be done a couple of ways one of which is shown below using a dial indicator. It’s attached to the lathe’s bed via a magnetic base then the contact point is set against the face of the blank shown below. The blank is spun and the amount of wobble is read on the dial. Squaring is an iterative process of finding the high and low points then tapping the high point toward the low side half the total wobble then repeating until the high/low difference is acceptable. After the blank was square, I checked to see how far the reference hole was from the point of the live center and it was just a tiny bit off. Some calculations showed that to get the 3/16” total wobble the reference hole only needed to be out of square by .4 degrees or .015”. However, I still need an accurate reference point so when taking the blank in and out it can be set up square.
Next Up – Fixing Reference Hole, Body Face Template & Turning 1st Body Face
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