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Topic: First Skirt Ever! Whatcha think? plus Circle Skirt Discussion  (Read 7700 times)
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keeperrox
« on: July 23, 2007 01:15:04 PM »

Okay, so I've never made a clothing item before.  I was digging through my very meager stash and found a random piece of black, white, and silver 2-way stretch fabric about 9-10 inches wide and 60 inches long and a huge piece of light blue jersey.  I am flying to Colorado for a wedding later this week and I wanted a comfortable, yet presentable skirt for traveling.

I ordered Sew What! (along with Sew U) a week ago, but Amazon still hasn't shipped it!!! Angry  However, I wanted it NOW!

I turned the striped fabric into the waist band and the jersey into a circle skirt.  Here is the outcome:


Front


Back

I like it and I will definitely wear it for the trip.  However, there are definitely some problems and I was hoping I could get some suggestions.

Problem #1

I thought I understood how to cut out a circle skirt.  I measured the waist band and got 47 inches.  I did some rusty geometery and came up with a radius of approx. 7.5 inches.  So, I folded my fabric panel in quarters, measured 7.5 inches down from the corner on each edge and a couple of places in between and then cut out the quarter circle.  Cutting the bottom edge was not a problem.

However, when I opened it up, it ended up being almost 11.5 inches too big around the center hole.  What did I do wrong?


This also leads me to:

Problem #2

I attached the back of the waistband to the fabric and cut off the extra width.  This was actually a good thing, because when I folded the fabric over I was able to sew a straight line instead of a tube, but I digress.  When I sewed up the seam, it doesn't lay nicely.  I thought maybe I didn't sew it straight (even though I CAN sew a straight line), but I double checked and it is straight.

Here is the skirt with the seam at the back, which is how I intended to wear it:



Here is the skirt with the seam at the side, which is how it looks a little better, but I don't want to wear it that way:







I would like to make more of these, because it is super comfy, yet nice enough to wear to work (I'm a teacher).  However, I would like to know how to fix these problems before I buy more fabric and start cutting.

Phew!  If you made it this far, I thank you.  If you answer any of my questions, I offer you my first born child.
« Last Edit: July 23, 2007 10:55:36 PM by keeperrox » THIS ROCKS   Logged
karls_mommy
« Reply #1 on: July 23, 2007 01:37:55 PM »

Okay, I am of no help with your questions, BUT, I wanted to say I think it looks very cute and comfy.  The mix of fabrics/colors makes it look punky.  Great job for you first unassisted skirt!
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thetheLizard
« Reply #2 on: July 23, 2007 02:38:43 PM »

I wish I could help with the problems, but they are the same problems I have making circle skirts! I love them to death, but the math never turns out right. We aren't the only ones though, one of my friends made a circle skirt that she gave to me because it didn't fit her. Which is fabulous, because it's this soft red cotton tshirt material, i think. I await the answer so I can make my own.
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hongkongfooye
« Reply #3 on: July 23, 2007 02:40:51 PM »

about the waist band it happens to everyone because craft-people arent usually math people. There is something out there that says they waist is about 4 times the the length of the hole you should cut. That is very wrong. Circumference= PI x Rsquared In other words if your waist was 42in that is C. Then you have Pi So 42= 3.14x Rsquared.
But I am a craft person and do not know the answer to that math problem. But I am sure a calculator does.
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sterlingmf
« Reply #4 on: July 23, 2007 02:41:30 PM »

I don't know either, being a newbie, but I do want to say I very much like your skirt. Those have got to be the most comfortable looking things around!
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geminikitty
« Reply #5 on: July 23, 2007 02:55:53 PM »

Your maths is correct, the circumference of a circle is equal to 2 times pi times r.  The amount of seam allowance will effect the circle circumference, even if it's only 1 cm it will change the actual circumference by a bit. You need to cut the circle so that the stitching line is 42 inches.

I think the issue is the the jersey has stretched when you've gone to attach it to the skirt, knits are notorious for this type of bad behaviour.

The grain of the fabric (the way it runs) is the issue with the back seam. Because the skirt is circular you may be sewing on the bias (cross grain) of the knit and this is going to throw things off kilter.
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keeperrox
« Reply #6 on: July 23, 2007 02:57:53 PM »

about the waist band it happens to everyone because craft-people arent usually math people. There is something out there that says they waist is about 4 times the the length of the hole you should cut. That is very wrong. Circumference= PI x Rsquared In other words if your waist was 42in that is C. Then you have Pi So 42= 3.14x Rsquared.
But I am a craft person and do not know the answer to that math problem. But I am sure a calculator does.

I did find the radius using "math", though. 

C= 2pir
My circumference, or length of my waistband was 47.5, so:

47.5 = 2pir
47.5/2pi = r
r = 7.5598598
I used 7.5 for my measurement.

And then I measured and cut like this (dark blue are the folded edges, light blue are the open edges, the red straight lines are my measurements, and the red curved lines are my cutting lines):



Your maths is correct, the circumference of a circle is equal to 2 times pi times r.  The amount of seam allowance will effect the circle circumference, even if it's only 1 cm it will change the actual circumference by a bit. You need to cut the circle so that the stitching line is 42 inches.

I think the issue is the the jersey has stretched when you've gone to attach it to the skirt, knits are notorious for this type of bad behaviour.

The grain of the fabric (the way it runs) is the issue with the back seam. Because the skirt is circular you may be sewing on the bias (cross grain) of the knit and this is going to throw things off kilter.

Okay, so you posted while I was typing the above, and now I'm even more confused!  Cheesy

I pinned the waistband around me and cut it first.  I measured that piece and and that's where I got the 47.5 for the circumference from.  If I did the math correctly, why then, when I went to cut using the above diagram, did it not work?  I mean, this wasn't an inch or two off.  It was almost a foot (11.5 inches) off!
« Last Edit: July 23, 2007 08:27:27 PM by keeperrox » THIS ROCKS   Logged
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« Reply #7 on: July 23, 2007 09:41:10 PM »

Okay...   I think the problem is with the equation used.. 
You used C=2Pir

but you should have used C= Pi times r squared

That would have really changed the outcome, i got a little less than 4 when I did the math, and since you quartered it, then if you multiplied that out you would be about a foot off in measurement.

47.5= 3.14*r squared
15.12=r squared
3.57(ish)=r

That is the equation that I found when trying to figure out how to do the radius...  hope it helps.... Smiley
« Last Edit: July 23, 2007 09:41:41 PM by Snootzie » THIS ROCKS   Logged

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Kayja
« Reply #8 on: July 23, 2007 10:03:36 PM »

2*pi*r is the right equation. 2*pi*r-squared is for area.

If you forgot to take into account the seam allowance (by mesauring 7.5 minus the seam allowance from the corner) you should've only been out about 4 inches, not 12.

I think Geminikitty was trying to say that the fabric, by nature, will stretch out of shape, which may be enough to ruin the math.

Another possibility is that not all the layers were perfectly flat when you cut them, so it may've been 7.5 inches in on the top layer but 8 or 8.5 on the bottom.

For next time, you should try cutting at least a couple inches smaller than math would suggest. That's enough for a seam allowance plus a little oops room. You can always make the hole bigger, you can never make it smaller.
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keeperrox
« Reply #9 on: July 23, 2007 10:43:50 PM »

2*pi*r is the right equation. pi*r-squared is for area.

Phew!  I thought I was going crazy for a second there.  I may teach History, but I did make it all the way through Calc in college with an "A". 

You also made some other great points that I'd like to address:

Quote
If you forgot to take into account the seam allowance (by mesauring 7.5 minus the seam allowance from the corner) you should've only been out about 4 inches, not 12.

I think Geminikitty was trying to say that the fabric, by nature, will stretch out of shape, which may be enough to ruin the math.

It's true, I didn't take seam allowances into account and by nature this fabric stretches, but it's good to know for next time.  However, when I tried just the "donut" on, it wasn't even close.  I would think that at least the very top of the skirt should have fit the 47.5" circumference.  So, there was definitely something wrong in the way I cut it out.

Quote
Another possibility is that not all the layers were perfectly flat when you cut them, so it may've been 7.5 inches in on the top layer but 8 or 8.5 on the bottom.

I just checked the scrap that was left over from the center and made a couple of measurements intersecting the center point.  All diameter measurements were 15 and radii were 7.5, so the layers were definitely flat.  Also, I think this would have messed up the way those bottom layers fell once the skirt was put on, but the hemline is pretty straight.  However, this is definitely a great tip for others with this problem who are reading this thread.

Quote
For next time, you should try cutting at least a couple inches smaller than math would suggest. That's enough for a seam allowance plus a little oops room. You can always make the hole bigger, you can never make it smaller.

I will definitely be cutting smaller the next time, especially if I can't get this figured out.  However, it would be nice to know how to cut it correctly the first time! Cheesy  Thanks Kayja and everyone else who has replied!  Keep the tips coming, though... I am determined to get this figured out!!! Wink
« Last Edit: July 23, 2007 10:54:03 PM by keeperrox » THIS ROCKS   Logged
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