I call this bowl "The Clow Bowl" for its general shape, but you could call it a star bowl, since we will be making it out of a star formed wood blank. Looking at this bowl from above will make it look like a perfect five point star, or a pentagram.
Step 1: Preparing Your Blank
So you've decided to make a claw bowl! A bold move on your part my friend!!
Now the first step is to prepare your blank. In this case I had an already rounded piece of wood stock, of tulipwood, which I've never worked before, so I didn't know what to expect as far as quality of wood, but it doesn't matter as long as you follow these few simple steps.
Materials needed in this step:
1. A wood blank.
2. A ruler.
3. A compass.
4. A protractor.
You will need to measure the shortest width of your blank, since that would be as large as your bowl will ever going to get. Once you've done that, spread your compass to half that measurement, so you could draw that sized circle onto your blank. Do so (mark the circle).
Next, using the ruler, mark a line from a point of your choice along the circumference of your circle to the center.
Using your protractor mark a point 72 degrees offset from your first line, and draw a line crossing that point and the center or the circle. Continue to do so until you've divided your circle into 5 segments. Be as accurate as possible, it's crucial to the process.
Now connect each end point on your circumference to it's opposite two furthest points (intersecting lines and circumference points), and do this for the rest of the 4 points left. This will mark your star, as you can see in the first image of this step.
Step 2: Cutting and Cleaning Your Star
In this step we will cut and clean our star. If you have a bandsaw, or a large scrollsaw, you're lucky and I envy you. I don't, so I'll be using my jigsaw and a hacksaw (since my jigsaw wasn't long enough to clear the height of my blank).
You will need:
1. A jigsaw (also known as a jacksaw in some parts of the world).
2. A hacksaw, or a thin saw of any kind.
3. A sharp woodworking chisel. It can be the cheapest kind, as long as you keep it sharp.
4. A platform to clamp the star to (in my case I used my tablesaw platform).
5. Some kind of clamps (I used cheap bar clamps, again, since it's all I have).
6. A sanding apparatus (Sanding wheel, belt sander, drill mounted sanding disk, or even a sanding block).
Clamp your star to the platform you'll be using (table of sorts), align the jigsaw to one of the lines, and go at it! Cut a few inches, and when the grove you've made is long enough, you can finish the cut using the hacksaw. Cut all the way to where the lines of the star arms meet, but not beyond it!! Also, it is better to err and cut outside the lines and sand it flush than cutting inside the lines, which will make your form not uniform.
Go on and cut out all the outlines of your star until you are left with a nicely shaped star looking wood blank. Use the chisel to clean the corners where your cuts meet, it will save you work sanding later.
Using your sanding apparatus (I'm using a 12 inch sanding wheel I made out of plywood mounted on my lathe) to sand the star to its actual shape, the more accurate you will be, the nicer and more balanced your bowl will be.
Step 3: Mounting Your Star Onto the Lathe
There is not much to say about this step, but I'll find a few words nonetheless!
You will need:
1. A drill with a drill bit corresponding to your woodworm screw.
2. A chuck on your lathe.
3. A lathe.
Drill a hole in the center of your star. I can't stress enough how important it is to drill this hole in the exact center, if you will not, the points of the star would not be even. There is no way around it.
Once you have your hole drilled, screw the star on to the woodworm screw as tightly as you can. Make sure when screwing on the star that you hold it parallel to the bed of the lathe. Give it a spin, see how it turns!
Step 4: Shaping the Bottom of the Bowl
Now the star is safely (relatively) mounted on your lathe, we will shape the bottom of the bowl. My tools of choice here are a parting tool, a round nose scraper (which I don't have a picture of, but will be shown in the video) and a bowl gouge. We will use the parting tool to create a mortice for us to mount the bowl in reverse once we finish the bottom so we could work on the top.
1. Sanding paper.
2. Wooden block.
Using the parting tool, cut a mortise that will fit the jaws of your chuck in expansion mode. My chuck's jaws are 2 inches when closed all the way, so I made my mortice a little larger than that (5 cm jaws, so I cut a 5.3 cm wide mortice).
Once the mortice is ready, we can use the bowl gouge to to shape the bottom of the bowl. First I shape the bottom into a general curve, this will flatten out our shape. My blank was not level, two of the star's fingers were higher in depth than the others (or shorted in width, depending on your point of view), and this took care of that, making all the fingers the same width/height.
Going on from there, we'll create the curve that comes from the base of the bowl (remember to leave enough meat around the mortise so your chuck jaws won't split the wood when you expend them inside the mortise), and the under cut that will give our star that unique claw shape, and we will finish the shape off with a sharp angled incline to the outside and soon to be top of the bowl, to create the finger tips.
Sand down the bottom of the bowl. There is no escaping this, other than the very base of the bowl which you can sand under power of the lathe, the rest will have to be hand sanded, slowly, for a long time, there is too much air between the fingers to sand it properly under power. If you try, you will only sand one side of each finger, and it will distort the shape of the claw. You can see I've also used a piece of wood with some sanding paper held on to it with a couple of tacks. This makes the sanding of the flat surfaces on the sides of the fingers easier and more precise.
You will also use the same block while sanding the other side of the bowl.
Step 5: Shaping the Top of the Bowl
Once you've finished sanding the bottom of your bowl, you can screw the bowl off the woodworm screw, and mount the bowl directly to the chuck using the mortise we made in the last step.
Hollow out the center of the bowl as shown using the tool of your choice. Mine was my almost worn out spindle gouge, but a bowl gouge will work, even a round nose scraper.
Once you've hollowed out the center of the bowl to the depth you would like your bowl to be, you can start working on the fingers of the bowl. Take this slowly. I stopped the lathe after each cut to make sure I'm cutting at the right place, to the right depth and form, and that no piece or tip of finger flew off while I was cutting, the wood in this orientation is brittle and can simply break off. This would be a good point to remind you that standing in front of a lathe should always be when you have a face mask to protect your face from flying debris.
Slowly cut the tips of the fingers to width, and the base of the fingers to the same width and follow the curve you've defined on the bottom of the bowl. You might want to change the curvature of the bowl walls as you cut more and more material off the fingers toward the base of the bowl.
Step 6: Sanding, Sanding, and Oh Yeah, More Sanding!!
The title of this step says it all. Sand away my friend. This wood was so punky (rotten soft wood) and the tearout (fibers of wood tearing out instead of being cut smooth and flat) was so bad I sanded this piece for 4 hours to get it to a finished surface. By hand.
As you can see I've used the same wood block as before, which worked perfectly. I also decided at some point to make the fingers rounded, so it will look more organic. A good choice, I think, seeing the results.
Step 7: Applying a Finish
My finish of choice for odd shaped creations is boiled linseed oil. Just pour some on a paper towel and slap it on the bowl. Use as much oil as you can, soaking the wood more and more until the wood doesn't absorb any more oil, you can see it does so when the oil simply remains in the surface of the wood (in the first couple of images you can see the surface of the bowl is matt, meaning the oil soaked in, while in the penultimate picture it's shiny since the oil remains on the surface of the wood). Once the bowl is soaked up, use a clean paper towel to wipe off the excess oil.
Step 8: Unmount Your Bowl and Enjoy It!
You can take your bowl off the lathe now, apply some oil to the base of the bowl, inside the mortise, and on any point you missed. Play around with your bowl as if it was an alien hatchling trying to attach itself to your face, make sure you enjoy the process, or else why did you go through all that trouble?!! ;)
Thank you, and I hope to see you soon with more interesting Instructables!