How Do You Knit A Round Shape On Straight Needles?
You can’t knit something round with straight needles. Straight needles do shapes consisting of squares, rectangles and triangles and combinations thereof, ie things with straight edges. That’s all they can do. With the increasing method suggested by the other answerer, at best you can get half of an ellipse (football shape). It would actually be an ellipse made of triangles, so wouldn’t have a smooth edge. It also is not a beginner technique, especially since you’d have to design the increases. Why are there no patterns or instructions for doing this available? Because it would be insanely difficult to make straight needles knit something they aren’t designed to knit. So everyone who truly wants a circle, or something round enough to pass for a circle, simply knits them on double points because it is far easier to learn to use double points than it would be try try to cobble together some way to fake it with straights. One hour to learn double points compared to dozens of hours at leas