Circle Skirt tutorial, part 2: 1/2 and 3/4 circles

According to Google Analytics, my Circle Skirt tutorial is the second most popular hit on my blog, and gets more searches than any other page.  How fun is that?  I'm pleased that there is so much interest!  I recently had a question regarding drafting a pattern for a 3/4 or 1/2 circle skirt, and how that would differ.  Since there is a bit more math involved, I thought that it deserved a post of it's own.
As you probably have surmised, a circle skirt is just a big doughnut, with the waist measurement as the circumference of the inner circle and the length as the distance between the inner and outer circles.  When you change this to a skirt that is less than a full circle, you now have just a segment of a circle (an arc) as your inner and outer measurements, so instead of using the formula for the circumference of a circle to find the radius of your inner arc, you need the formula for arc length.  I'm not going to bore you with derivations and reductions (although if you are interested, here is where I got my geometry refresher), but the formula you'll need to draft your pattern is this:

r(radius)=360l(arc length)/2 pi m(angle).

If that makes you nervous, don't worry!  I'm going to take you through the steps for a 1/2 or 3/4 circle skirt.  It'll be easy!  Stick with me.

OK, here is the info that you will need: Your waist measurement (That is, where you want the skirt to sit) and the final length that you want your skirt.  Measure this from your waist to wherever you want the skirt to end.  Let's get to work!  I'm going to show you how to draft the waist part of the1/2 and 3/4 circle skirt.

If you've already watched the video on the Circle Skirt tutorial, then you are ready to start.  If you haven't please go there and watch it, so that you know what I'm talking about.  Don't worry, it's short.  The first thing that we need to calculate is the radius of our inner arc.  The formula up there will give it to us.  For the 1/2 circle m=180 and for the 3/4 circle m=270.  The formula you will need to use is:

r=l/pi for the 1/2 circle
r=(2l)/(3 pi) for the 3/4 circle
where l=your waist measurement.

For example, if your waist measurement is 26, you would have a 8.3 inch radius for your 1/2 circle skirt and a 5.5 inch radius for your 3/4 circle skirt.
Now, we have to draft.  The first thing to do is choose a midpoint on your drafting paper, and draw lines representing the edges of your skirt.  For the 1/2 circle, that would be a straight line (that is a 180 degree angle)

and for the 3/4 circle, you would draw a 90 degree (270 on the skirt side) angle.  This is easier if you are working on or with gridded paper.

You'll use these lines as the boundary of your pattern piece, since you aren't making a full circle, so draw them as long as you plan your skirt to be, plus the radius you calculated.  This will be the total size of your pattern piece and the full size of your skirt, if you seamed the long edges together.  You'll probably need a pretty big piece of tracing paper for this...
For the waist measurement, you already know what to do if you watched the video.  Use the radius you calculated to draw the arc you need for your waist measurement.  Here's what it looks like with our hypothetical 26 inch waist.
For the 1/2 circle,

and for the 3/4 circle.

Now to complete the pattern piece, make your outer arc, using the length of your finished skirt plus the radius.  Since you drew your initial lines to this measurement, you should just have to connect the endpoints, but with a semicircle.  Your final pattern pieces should look like either a half circle or a 3/4 circle.  You can even try it on to see how your skirt will fit!  To get a pattern piece, fold this giant thing in half.  You can either make this cut on the fold (if your fabric is wide enough) or you can cut two and use one as the front of your skirt and one as the back.
Now to finish your skirt, head over to the original tutorial to see how to subdivide your pattern piece into panels, and how to construct your skirt.  I hope this is helpful!
Happy sewing!

Threadbanger

...featured my circle skirt tutorial in their weekly roundup!  I so never thought I'd be that cool.  I need to make a red top to go with that skirt...

I also discovered that if you Google "circle skirt" the tutorial appears on the first page!  I guess I'm getting a lot of hits, which I think is great!  I hope it helps someone make themselves a great skirt.

Circle Skirt How-to

**If you surfed here looking for a half or 3/4 circle skirt, you can find a separate tutorial for drafting those patterns.  Just click here!

I wish all days could be like today. The kids (mostly) behaved. The weather was pleasant. And I finished the most fabulous skirt! I've been completely in love with the 50's fit & flare look, and so, a circle skirt was an essential piece to that look. I also have always liked the look of a black and white palette, and so, my black and white circle skirt was born.

I know that a circle skirt is pretty simple. Thanks to vegbee's awesome tutorial I had a place to start. Vegbee's version is great. It features and elastic waist, which is comfy, easy to do and easy on the fit. The only problem with an elastic waist is that it can add some bulk, if you have a significant difference between your waist and hip measurements, which I do. After two kids, I have enough bulk in the waist, so I decided that a waistband and zipper were the way to go for me. I also hate hemming. Especially curves. So, after reading about a hem facing on oliver + s, I decided to try that, too.

Let's learn together! I'll show you how it all went.

The first step is to create your pattern. Since a circle skirt is exactly what it says - a circle with a hole in the middle - two measurements and a little geometry is all you need. Don't worry, it's only a little geometry. The measurements you need are 1. your waist and 2. the length you would like your skirt to be, measured from the waist to the hemline. Since it is unlikely that you will be able to find fabric wide enough to make the entire circle, let's make our initial pattern piece a half circle. Your waist measurement is the circumference of the hole in the middle of your circle. So, take your waist measurement, divide by 3.14 (pi) and divide by 2. This is the radius of your center circle. I know this isn't making much sense without a visual. Fortunately, there's video...

OK, so once you have your half-circle, you can decide if you want panels or not. My skirt has six panels, with 2 alternating prints, so 3 of each. To cut out my actual pattern piece, I carefully folded my half-circle into thirds, then added seam allowances. This was the pattern for my 6 panels.

The other two pieces you will need are a waistband and a hem facing. The waistband is easy. It is a big rectangle, measuring (your waist + 2 inches (for the tabs) + seam allowances) long by (desired width x 2 + seam allowances). I used one inch for my desired width - that is, however tall you want your waistband to be. For the hem facing, you will need an exact copy of the bottom few inches of your skirt. I decided to do the facing in four parts, so that my seam allowances wouldn't overlap and get bulky. I again folded my half-circle, this time just in half, and traced the bottom 3 inches, then added seam allowances. Be sure to measure carefully - this needs to fit pretty exactly.

Now, let's put it together!!

For my six panels, I first attached them together in pairs. If you are alternating fabrics, make sure that when you are sewing your pairs together, that you have the same print on the top and sew the same side seam. So, in the picture, you can see that my three pairs are all together, with the black fabric on top. I seamed them all along the right side. I also installed my zipper at this point, between the first two panels that I seamed. I have a love-hate relationship with my zipper foot, so I am NOT going to talk about installing a zipper. There are excellent instructions included with the zipper when you buy it. Follow those. I should have.

Now attach all of your panels together. When you place them right sides together, they should alternate, as you can see below.
Pretty panels all in a row! Just one more seam to go!
Once you are all seamed together, it is time to add the waistband. Be sure to fuse some interfacing to the wrong side, within the seam allowances. Find the center of your waistband and pin it (right sides together) to the seam opposite your zipper, then pin all around.
When you finish, you should have a tab that hangs off the end. This is where your button or hook and eye will go.
Stitch down your waistband where you just pinned. Now press up about 1/2 inch on the free edge. This will become the inside of your waistband and will cover your seam allowance.
With right sides of the waistband together, seam the two overhanging ends.
Trim the seam allowances and clip the corner, then turn them right side out. It should look like this when you're done. You made a little "pocket" to hold your seam allowance!
Now press your waistband down, pinning it on the right side, making sure to catch the folded inside edge of the waistband as you pin. You can see my pin just where my iron has been.
Now from the right side, topstitch the waistband close to the seam. You can also stitch in the ditch if you don't want any topstitching to show, but make sure that you catch the underside of the waistband. It's a bit trickier. Attach your closure of choice to the tabs. I used a hook and bar.

Waistband done! On to the hem facing. Don't forget that with a circle skirt there are areas that are cut on the bias. Be sure that you hang your skirt for at least 24 hours to let the bias set before you hem it. Otherwise, your hem could ripple after the fact. OK, bias set - let's go. Seam all of your facing pieces together to make a BIG circle. Finish the inner edge of the circle with either a serger if you are so blessed or just an overcast stitch. Or I guess you could hem it, but that would defeat the purpose...
Now, this is the painstaking part. Pin it, right sides together, to your skirt. I laid it out on the living room floor while the kids where sleeping. Start at a random spot and just go around the skirt until you get it all lined up the way you like it. It took me three revolutions around the skirt.
Once it's pinned, sew away. Then clip the seam allowance every few inches. This will help it lie nice and flat when you flip it.
OK, now that it's all clipped, flip it wrong sides together and press. Be sure to press it so that you can see a bit of your pretty fabric on the inside, so that you know that no one can see your facing.
Now stitch down the facing and you are done!! I chose to hand stitch it because I wanted it to be truly invisible, but do whatever floats your boat.
See, it really is a circle!Now, let's see yours!

ETA 8/11/2010: I've noticed that quite a few of you are popping over see a half circle skirt, and since Anne commented that she was interested in a 3/4 circle, I added an additional mini-tutorial to include drafting the pattern pieces for a 1/2 and 3/4 circle skirt.  The math is a smidge more complicated, but hopefully the tutorial makes it clear.  Click here for the tute!