How to sew a cone
It’s no secret that I’m an engineer. I’m probably more proud than I should be about my totally geeky profession, but it works for me. There are some pitfalls when it comes to the mind set of an engineer.When it comes to geometry and math, it must be done right. Don’t get me wrong, I drape, cut to fit, estimate and “make it work” like the best of them but somethings just need to be done right. If you think math and geometry has no place in crafts, then you have never quilted.
Let me explain the frustration. Recently my eldest sister decided to make a reading tent for her daughters. You’ve seen them before. They kind of look like castles and you hang them from the ceiling. Well, when Kellie realized that having 3 kids under the age of 2 didn’t leave her much time to do sewing projects, I offered to finish it for her (pictures to come later). I looked online at various blogs who had tutorials and I was blow away by the lack of accuracy in making the upper cone portion. I can’t tell you how many just said “cut a circle and adjust to fit.” That’s a giant waste of fabric! So here it is, the right way to make a cone!
H: The total height of your cone
S: The length of the sloped side. If this were a triangle instead of the cone, this would be the length of one of the sides.
D: The diameter of the base (circle). If this were a triangle instead of a cone, this would be the length along the bottom of the triangle.
Ok, so now you need to figure out what kind of cone you are going to make. Is it going to be short and fat or tall and skinny? The easy way to figure this out is to compare the diameter of the base to the height of the cone.
For each option, you’ll need to calculate S. Don’t roll your eyes at me. I have a way to cheat. Use this site. For side A type in your value for H. For side B type in your value for 1/2D. Press calculate and side C is your value for S. Moving on…
Here’s option 1. This is a short, fat cone. Your cut out should look something like this. It should be more than a half circle, but less than a whole circle. (If you don’t have Pi on your calculator, use 3.14)
Ok, no go forth an make cones correct, the first time, with out guessing….
A very geeky crafter (Jenny)