I use safety pins about a hand width apart in all directions. It was an investment to start with to purchase that many safety pins but I have used them over and over. I'm reading all the comments about pins falling out and poking and have to assume those posts are talking about straight pins. I would never use straight pins on something that has to be moved around so much as a quilt in a machine. I also use a hand tool called Kwik Klip by Paula Jean Creations to close and open my safety pins as I'm pinning and unpinning. Really makes it much easier and wouldn't be without it. I've never had a problem with puckers using the safety pin method.