From the outside of the bowl, according to your preferred profile, we need to install the bottom of the bowl so that it can be attached to the lathe. This will remove material from inside the bowl. This is called “Reversible Jamming” and “Four-Jaw Cup” used to attach the bow to your lathe with the inside of the bow facing the tail section. The bottom of the bowl was turned flat and square to the lathe; Turn the pin about an inch high to the bottom of the bowl. I prefer to use a large-diameter pipe, and then create a recessed dovetail, cut into a pipe about 3/8 inch deep. The dovetail diameter must be within the range of the Scroll Chuck Jaws. For heavy bowls, I prefer the recessed dovetail; this method is stronger. Smaller bowls that you can rotate with a smaller nozzle and hold the nozzle outside.
Remove the bowl from the lathe and remove the faceplate and attach the cartridge in the recess of the dovetail. The best way; is to attach the chuck to the bowl, before you connect the spiral chuck to the lathe, this provides a better alignment. Then connect the cartridge to the head stock. If the cartridge is not installed correctly in the recess of the dovetail, the bowl will have a swing. A slight wobble is in order because the bowl will be re-tuned after it is dried. The jaws are numbered in a scrollable cartridge; mark the bottom of the bowl so that it fits one of the jaws so that it can be put back in the same position after drying.
After the bowl has been attached to a rolling chuck and connected to the head of the lathe. Natural side grids have an uneven surface and will cause a lot of stress for the chuck's holding capacity when you start turning inward. To ensure safety and to support the bowl, use tail stock for support, the same as in article 2.
Place the banjo between the cup and the tail; with the tool resting at the correct height, turn the bowl by hand to ensure that the bowl rotates freely. Using Bowl Gouge and starting near the 60-degree cone in the living center, start carefully and slow down the cutting of the inside of the bowl, as soon as you have some depth and cutting, you can even move faster. As you move deeper into the bowl, you will need to move the tool closer to the surface of your work area. If any tool extends beyond the tool, it causes a greater vibration.
The distance that a tool can go beyond the tool depends on the size of the tool you are using; it is best to follow the manufacturer’s recommendations. Large-diameter tools can protrude beyond the limits of the instrumental rest than small-diameter tools same thickness.
The bowl must be washed after removing the material inside the bowl; This will be discussed in the next article. The thickness should be about 1 inch thick, sides and bottom, except for the deepening of the dovetail, which should be of greater thickness. At this point, much of the weight has been removed, and you can draw tail stock. The sleeve remaining inside the bowl can be removed using Bowl Gouge or I prefer to use the big Forstner bit. Using a drill chuck mounted in the tailpiece feather, you can push the bit and remove the remaining wood; horizontal drill press. When the inside of the bowl is uniform; Use a round knife to smooth the inside of the bowl.
The attached link is a glossary of terminology for a lathe and related tools; http://www.turningtools.co.uk/glossary/glossary.html
