In woodworking, a circular plane may be needed for shaping and smoothing curved pieces of wood. Planes with a metal shaping surface, or sole, which can resemble the base of a rocking chair or an arc, may serve to fit concave or convex surfaces. Though not truly circular in shape, circular planes often can be adjusted to accommodate the degree of roundness or curve being worked. A handle, tension system, and base make up the plane, and it generally is used for projects such as furniture, winding staircases, decorative wood features, cabinetry, and boat building and repair.
Carpenters and woodworkers typically use planes for the finishing of pieces. Planes are not usually used for deep cutting or drastic resizing of wood. A circular plane is more likely to be used for shaving down bumps and irregularities to improve the smoothness and feel of the wood, as well as to gently draw out the natural pattern and contours of the wood itself. Being able to fit the plane to the project is usually an important part of crafting wood pieces.
When a circular plane is needed for a particular task, it is shaped specifically for the area to be worked. A flexible steel sole attached at the bottom of the plane may be manipulated by the turning of screws at the top of the plane that adjust the curvature of the sole. Most systems are adjustable in a way that allows for customization of the shape without loss of tension. This is usually important in using a plane, as too little tension will decrease the effectiveness of the plane when woodworking.
Using a plane can involve repetitive motion and some force to achieve the desired result. Producing rounded woodwork may be a challenge, as the surface may be more difficult to manipulate than a flat or square shape. Circular planes typically have a large, solid handle on top in order to lead the action of the bottom surface with sufficient force from the top. A heaviness in the materials used can help to maintain contact between the plane and the surface being worked, so that the sole is not slipping off as it is moved. Achieving smoothness in the finished product often requires going over an area repeatedly, and a circular plane usually is designed with sufficient weight to hug the wood but not too much to make it unwieldy for the user.