Draw a Circle 22.5 Inches

The circle is, in my apprehensive opinion, the Queen of the geometric shapes. Don't get me wrong; I like all those squares, rectangles, triangles, octagons, and whatnot; but the circle is the coolest of the bunch: polish and pretty and incessantly useful. All the same, trying to draw a perfect circle without a pattern is a challenge, and figuring out the proper size of an opening into which a circle can be inserted requires working with Pi (or π), which is not the delicious kind you can swallow with a bit of ice cream. We're here today to help yous with the steps you lot've forgotten since loftier schoolhouse geometry course (or perhaps never learned because you were also busy passing notes with Susan Ellery!). We'll show you the parts of a circle, how wide to cut textile to fit a circle, and how to draw a circle without a design. We've also included a handy conversion from decimals to inches, which is necessary when working with Pi.

The parts of a circle

Let's start with remembering what all the parts of a circumvolve are chosen and how Pi (π) fits into the mix.

Radius: the altitude from the center of the circle to the outside edge

Diameter: the distance across a circle through its centre point

Circumference: the distance effectually the outer edge of a circle

π or Pi: the name given to the ratio of a circle's circumference to its diameter, expressed as the decimal 3.14

How wide to cut fabric to fit a circle

If you know the diameter of your circumvolve, you tin use a standard formula to figure out the width of the material cut needed to make a tube. That width is the circumference of the circle that volition be inserted into the tube (we accept a great step-by-stride tutorial on how to insert a circle into a tube).

The formula: iii.14 (π) x diameter = circumference

Example: You lot want a finished 12″ diameter base of operations (a 12″ diameter circle) in a duffle purse.

3.xiv x 12 inches = 37.68 inches

(This works with the metric organization equally well: 3.14 10 30 cm = 94.2 cm)

An important step many people miss at this point is forgetting to add extra (to both pieces) for the seam allowance. If yous utilize a standard ½" seam allowance, you need to add 1″ to the diameter of your circle ( the diameter increases by double the seam allowance)and one″ to the width of your fabric (½" for both sides of the seam assart). In our instance, that means:

The circle should beginning as thirteen″ in diameter.

The fabric should exist 38.68″ in width

The height of your fabric cutting is variable and dependent on your project. For instance, a tall duffle handbag might be 30″ in height whereas a shorter bucket might be merely 10″.

Converting a Decimal to a United states of america Ruler Measurement

If you lot are using Pi, remember it ever returns a decimal number. If yous already deal with the metric arrangement, y'all rock –  no conversion necessary.

For those of the states in the world of inches, you lot need to find a yardage conversion.

In our case we take 38.68 inches. Harumph! The table below will give you a close-enough ruler match.

The decimal .68 is closest to .63 or ⅝". We tin utilize 38⅝" as the width of the fabric piece y'all are cutting for your tube.

How to Draw a Circle

If you have a supply of big compasses, you lot're in luck, and tin hands draw yourself all sizes of circles. But you can also easily make your ain compass to draw a circumvolve.

To start, yous need to know how big you want your circle (the diameter). For our ongoing case, we want a 13″ diameter circumvolve

To depict a circumvolve y'all need to know its radius. As you learned above in the first section, the radius is one half of the diameter. In our example, one one-half of 13″ is 6½".

The full circle method

1. Employ a canvas of lightweight paper (graph or blueprint paper works well) that is at least 1″ larger all around than the circumvolve you desire to depict.
2. Cut a piece of string nigh iv″ – 5″ longer than your radius. Nosotros used a 10″ length of string.
3. Tie one end of the string to a brusque pencil.
4. Identify the indicate of the pencil toward the outer edge of the paper with enough room from the edge to make a full sweep.
5. Measure from where the point of the pencil touches the paper backwards by the length of the radius (in this instance 6½").
6. Pin direct through the string into the paper at that exact indicate.
7. Keeping the string taut, draw a perfect circle using your homemade compass.

The folded quarters method

1. Again, start with a square of lightweight newspaper at least one″ larger than the circumvolve you want to draw.
2. Fold the paper into quarters. Make sure your original foursquare is fifty-fifty and true! Position the paper with its folded edges along the bottom and left side and the open up edges forth the acme and correct side.
3. Place a see-through ruler at the exact centre of the lesser left corner of your folded foursquare. Swing the ruler from the top to the bottom of the square, like a pendulum or compass, measuring and marking a dot at the 6½" point in 3 to four spots. You are creating a semi-circle arc. Make sure the end of the ruler at the corner point doesn't shift position.
   
4. Cut along the arc through all the layers and unfold the finished xiii″ circle. You can now use this paper pattern to cutting your fabric circle.

With your spiffy new circle, you lot can at present sew the side seam in the main fabric cut. Then pin the base to the resulting tube and sew the tube to the circle using a ½" seam allowance. The result is a 12″ diameter finished base.

As mentioned above, for more on this technique, see our tutorial: How to Insert a Flat Circumvolve Into a Tube.

payneounkentoot1954.blogspot.com

Source: https://sew4home.com/draw-and-measure-a-circle-without-a-pattern/