This is a relatively common build. Followers of Paul Seller's make and post images of "Seller's-inspired," "my-interpretation of," or "Purist" examples of his clock, which originally appeared on YouTube in a free online course he offered. This example of mine is in the "Purist" style. I typically look at pieces online or in a magazine and then draw a picture of what my take on a particular piece would be and come up with some measurements, which get refined a number of times, decide on a wood species, and hit the tools. The problem for me with this kind of adaptive learning is that half of the education, as in the instructional/teacher insights is omitted. I wanted to build my first Seller's clock as Paul did. I wanted to go through the processes he does. More than a clock, I wanted to understand how this master applied his trade, in terms of design, tool choice, order of steps, and methodology. And, I certainly wanted to do that...
Will I need a lathe or a special pattern?
When I hear someone say they make bowls, I immediately think of the lathe. However, nice bowls... Let me say that again. Nice bowls, indeed very nice bowls, can be made in any number of ways, Bowls can be carved, cut with a router, or made on a band saw, to name but a few. There are, in fact several ways, and several styles of bowls that can be made on the scroll saw. The bowl pictured here was made with a 7-1/2" square, 3/4" thick piece of mahogany. That's it; that's all the wood that was used. Patterns are available from several books, online stores, and catalogs, such as Steve Good's site, but honestly you really don't need a pattern at all. If you can draw circles with a compass, drill a hole using some type of angle guide, and tilt the table of a scroll saw, you got this! You can decide how big the base of your bowl will be and then you need only extend each ring 1/4" beyond the last, similar to a target. The width and the height of your bowl is determined by how many rings are cut. You can also decide the angle of the pitch. Most are between 20 - 30 degrees, This bowl is angled at 20 degrees.
What tools will I need?
Obviously, a scroll saw. Specifically, a modern pinless scroll saw equipped with a #5 Reverse Tooth blade. Painter's tape. You will also need a drill with a 1/32 bit, and sandpaper. I do recommend different types of sanding equipment for this project--whatever you have that will work. You will also need a couple of shop made jigs. The first is a press. Cut out two 12' x 12" pieces of 1/2" plywood. Drill a 5/16" hole in each corner. Two pieces of 1/4" threaded rod, cut in half, eight 1/4" wingnuts, and 8 washers finish the press. The second jig is a 1/2" thick by 3" long block with the angle you plan to use cut on one end. Any drill attachment that creates accurate angles or a drill press are better options, if one is available to you. Small diameter drill bits easily break, so they are often short. Using a block thicker than 1/2" would likely prevent you from drilling all the way through your piece.
Cutting out the rings and bottom.
Your bowl blank must be flat. There is a lot written on this topic elsewhere and too big to delve into here. But, if your board isn't flat, your bowl will rock Keeping in mind which side will be used as the inside bottom, cover the top and bottom with painter's tape. You're asking why do I need to do this if I'm not using a pattern? First, you are using a pattern; you're just making the pattern yourself. Second, the cut will ultimately be cleaner if the piece is protected from tear-out with tape. Place the piece bottom-side down on a table, as in what will be the outside of the bowl should be face down on the table. Draw your base. A three-inch to four-inch base is sufficient. Draw the rings, by increasing the size of the compass 1/4". Remember, each ring is increasing the overall height by 3/4" So, one ring makes a 1-1/2" tall bowl, two rings make a 2-1/4" tall bowl, etc. I usually find four to five rings to be sufficient for most bowls. Alternatively, you can simply draw what will be the outside ring first and then work in using the ring just cut to mark the outside of the next. This may sound odd but it will produce the most accurately aligned rings because it is custom cut.
You are looking at the inside of your bowl. Which way should the bowl pitch, toward you or toward the center? Toward you. Place your angle guide on the board so that it aligns the outside line of the bowl with the drill bill angling toward you. Drill the hole following the slope. Do the same for the inside of the ring. The drill bit will leave an impression. Some bowl makers off-set the drill, while some drill all the holes in line. I prefer in line on a circular bowl. Accuracy reduces sanding time, but will not eliminate it.
The table of the scroll saw needs to be tilted down 20 degrees to the left and the pattern cut counter-clockwise. Start with the outside ring. If you have any difficulty threading the blade through the hole use a small finishing nail or dental tool to clear the debris. A scratch awl is too big and will enlarge the hole. It's helpful to make a mark on each ring before cutting so they can be lined up again for the glue up. Cut out each ring in your pattern the same way, leaving an adequately sized base.
The glue-up.
Glue the rings together without the base and set it inside your press. After 1-1/2 hours remove the rings and scrape off excess partially dried glue. Return the scraped rings to the press and allow to fully dry. Now sand the rings smooth, inside and out. Glue on the base and return to the press. Follow the same procedure. That is, scrape after the glue has set up, return to the press until dry and then sand smooth.
The fancy dip.
If you'd like a fancy dip in one side like this bowl then return the table of the saw to a zero setting. Draw the dip in one side. Stand the bowl on its side and cut the dip. Because the bowl's sides are flared the side that's up it usually not in the way to cut a small dip.
Sanding and finishing.
Round over the top and bottom edges and sand thoroughly through 320 grit, removing all imperfections and glue residue. Apply three coats of spray shellac and lightly sand with 400 grit. The apply five coats of wipe-on polyurethane. I make my own using a 50/50 mix of odorless mineral spirits and polyurethane. Allow the polyurethane to dry at least five days before applying a paste wax. What? That's not food-safe? This is not a soup or cereal bowl and virtually all finishes, once dry, are reasonably safe. Have you ever eaten a French fry that fell off your plate onto the table? Are you okay?
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