How to Crochet Circles , Bowls and Spheres.

 Call me slow, but something very strange has finally occurred to me. The formula for crocheting flat circles and round spheres is exactly the same?! "How can this be?" I ask myself. This I have to investigate!

Maths, sadly, is not my strong point. I do have a certificate that insists I have a certain level of understanding, but the minute the examiner said; "Pens down!" all knowledge instantly fled. So fear not we will keep it simple.

Let's start with a flat circle.

No matter what size of stitch you are working with the formula is exactly the same. The only difference is how many stitches you begin with.

 

UK	USA	Starting Stitch Count
Dc	Sc	6 stitches
Htr	Hdc	8 Stitches
Tr	Dc	12 Stitches
Dtr	Tr	15 Stitches

 

Round One of your circle begins with the starting number of stitches made into a magic ring. By following the formula below you will find that your circle increases by the same number of stitches, as the stitch count, on each round.

 

Standard Flat Circle Formula
Round 1	The starting number of stitches
Round 2	2 stitches in every stitch
Round 3	2 stitches in every 2nd stitch (1st, inc)
Round 4	2 stitches in every 3rd stitch (2sts, inc)
Round 5	2 stitches in every 4th stitch (3sts, inc)
Round 6	2 stitches in every 5th stitch (4sts, inc)
Round 7	2 stitches in every 6th stitch (5sts, inc)
And so on!

 

This formula is used most often because it is so easy to understand and remember. It has a flaw however. The increases start to stack up on top of each other and in the case of a Double crochet circle (Sc-USA) it starts to turn into a Hexagon. If I was awfully good at maths I would now give you a formula involving 𝛑. As I'm not here is the next best thing.

 

For this formula to work you need to know that 'Y' is the starting number of stitches minus one. So if you are working with Dc (Sc-USA) Y is 5. (6-1=5)

 

Adjusted Flat Circle Formula
Round 1	The starting number of stitches
Round 2	2 stitches in every stitch
Round 3	2 stitches in every 2nd stitch
Round 4	1st, inc, (2, inc) x Y, 1st
Round 5	2 stitches in every 4th stitch
Round 6	2sts, inc, (4sts, inc) x Y, 2sts
Round 7	2 stitches in every 6th stitch
Round 8	3sts, inc, (6sts, inc) x Y, 3sts
Round 9	2 stitches in every 8th stitch
Round10	4sts, inc, (8sts, inc) x Y, 4sts
And so on!

 

 Let's move onto Bowls

If you want to produce a flat bottomed bowl all you do is to make a flat circle to the required diameter. The next round is made into the back loop only and is worked with an even number of stitches without increase. It makes no difference if you work in a spiral as I have or in rounds joined with a slip stitch. From then on you work without increase to form the sides of your bowl.

 

 

Cones and round bottomed Bowls.

The reason this whole problem forced its way into my brain in the first place was that I was thinking about round bottomed bowls. I was wondering why so many Amigurumi patterns seem to begin with 6Dc (Sc-US). I decided to find out what happens if we begin with a different number of stitches. The cones above begin with 3Dc and 4Dc respectively.

Now I wonder what they would look like if I added a few even rounds without increases. The cones each have 8 rounds worked in a spiral and 3 even rounds.

Now I have added bowls beginning with 5Dc and 6Dc, each with 4 rounds worked even. If 6Dc makes a flat circle what happens if I use too many stitches to start? (Yes, I am that small child constantly asking, "Why?")

I produced another bowl starting with 8Dc and working 6 rounds even. The more even rounds I added, the more the sides seem to straighten and the more the rippling circle I had begun with started to flatten out. If this was an Amigurumi shapes which I was going to stuff the rippling would disappear altogether.

Spheres

Before I ask myself any more stupid questions lets rush on and ask about spheres! First of all what is the standard formula for a crochet sphere? There seems to be some argument on this point but what I tried seems to work out OK.

Work a flat circle to achieve your desired diameter. Work the same number of rounds again even, without increase. Decrease by the same number of rounds. The Sphere on the right has 6 rounds of increase, 6 rounds worked even and 6 rounds worked in decrease.

 

I have mentioned Ms Premise-Conclusion before. She has very kindly worked out a mathematical solution for all us non mathematically literate people. So the Sphere on the left is made using her Ideal Sphere pattern.

Any perfectly sensible person would have stopped at this point. But I felt the burning desire to know if what held true for a Dc Sphere (Sc-US) held true for other stitch heights. So while a Half-treble (Hdc-Us) circle begins with 8 sts I found that a Htr sphere begins with 7 sts. Otherwise it follows the same formula. So for the sphere here I worked 5 increase rounds, 5 rounds even and 5 decrease rounds.

Following that theory I worked a Treble (Dc-US) sphere starting with 10 stitches instead of 12. This ball is 4 rounds of increase, 4 rounds even and 4 of decrease.

I can only conclude that the reason any of this works is due to the stretchy qualities of crochet and that skilled stuffing is largely to responsible for well shaped spheres!

Fastening off...