Originally Posted by feline fanatic

The quilt sandwich is loaded on a rack that is perfectly square (if it wasn't the carriage that the machine rides on would never glide smoothly). If the quilt is out of square (and an inch or so is a LOT out of square) it won't load on the rack correctly and lay nice an flat in the exposed quilting area.

With most racks the quilt back is loaded with one end of the backing on what is called "take up roller" which will be taking up the completed quilt sandwich as the quilt is quilted and advanced on the frame. The bottom of the backing is rolled up on a different roller located at the front of the frame. One of the quilt top's edges is loaded on another roller (unless it is floated) also at the front of the machine and rolled up as well. At any given time, depending on the size of the LAQ's machine, only about 16" to 22" of the quilt is exposed for quilting.

The LAQ lines up the top, batting and backing and stitches a line of quilting across the top and attaches side tension clamps. Then we proceed with quilting. If the quilt is out of square in one corner even just an inch or two this problem gets amplified as the quilt is quilted and advanced. It is a lot of extra work to try and quilt and avoid the problems of an out of square quilt (which in my experience is ALWAYS accompanied by a wavy border or fullness in the middle). It can result in pleats, puckers or very exaggerated out of square quilt by the time the last lines of quilting are put in. Sometimes this isn't an issue for the person who pieced it sometimes it is and they tend to blame the LAQ for the problem.