Well, if you do long arm quilting for anyone be it for a business or a favour, you will encounter problems with quilt tops. There are many. I just finished one that presented a lot of challenges some of which I simply could not fix. Hand quilted squares that are squared up by pulling the threads up to shorten a side are simply not something one can fix. A bit of stretching as you quilt can make sure you do not catch the fabric but the unevenness will remain. The same is true for blocks that fold over the seams because they are too big.
Most of the problems I have coped with before but have not done it while floating a quilt top. So I pressed the top very carefully and steam helped a bit but in the end some things are there forever. I had not floated a top before but it is a great technique and less time consuming and less physical as you do not have to pin the top and roll it on the front. I am all for less time and less physical.
I followed some suggestions for tacking down the quilt edges as you go Oh the internet is a wealth of information for a quilter. Across the top and down each side was the recommended method. . Or up each side to avoid the ruching that can occur when the machine pushes the fabric ahead of it. You baste at each roll of the quilt.
Even a small amount of push can distort a border especially if the border is not sized to the quilt and is waving like a mad person in a crowd. This border was a wavy as an ocean shore. It was not fitted to the quilt top.
So, faced with a problem I tried to think of a way out of the predicament. I smoothed, pulled and smoothed and pulled but the waves kept coming but I began to realize if I smoothed from the inside to the outside of the border I could get places of relative calm i.e. in the direction of the waving. Here is a little presentation attached Simple pictures to try to illustrate my words. I should have taken pictures but it was not my own quilt.
It worked. The problem almost disappeared. So in the future I will baste across the borders; not up or down or across the bottom. Top is ok to baste normally but the sides and bottom present challenges. But if the top will not cooperate this would work as well. You can stitch over the basting but it pulls out easily.
What is taking longer now is the pinkie that the machine stitched as I tried to smooth one of the squares which was shoe horned into the quilt. No blood on the quilt though. :)