Making a circle with a given radius
Some of the Buildeazy woodworking projects include pieces that may have one, two or even three rounded or curved edges, such as the piece in the image below (fig.1).
This article explains how to make curved shapes such as those shown in the plan drawing below (fig.1).
Note: There are other ways of transferring various shapes from plan to wood. This particular method is aimed at those who have little knowledge of curvilinear forms i.e. curves, circles, that sort of stuff.
The drawing below is a ‘Chair Frame Detail’ plan from the How to build a Cape Cod Chair project.
Each curve is part of a circumference (the outer boundary of a circle).
Each curve has a different radius.
Curve (A) has a radius of 135mm (5 1/4″),
Curve (B) has a radius of 400m (15 3/4″),
Curve (C) has a radius of 150mm (6″).
What is a radius?
A diameter is a straight line across a circle through its center. The diameter is twice the length of the radius. The diameter is two radii.
Note: Radii is the plural of radius.INSTRUCTIONS
Cut three circles (each with the given radius) out of card in order to mark the curves A, B & C on the template (fig.1).
Insert a push pin through the arm 135mm (5 1/4″) from one end. Pin the arm to a sheet of card.
Rotate the arm in a circle using the push pin as the pivot point.
Hold a pencil at the end of the rotating arm to mark the circumference (perimeter or outside edge of the circle).
Once marked, remove the arm and cut out the circle.Mark and cut the other two circles (B & C in fig.1) with their given radii in the same manner as circle (A) was marked and cut.
Note: Radii is the plural of radius. One radius; two or more radii.