How to fix/avoid sever fullness on both of quilt?

[Casual Quilter]

I just finished a 54"w x 90"l T-shirt quilt, which ended up having a lot  of fullness on the bottom border.  Because I have a Lenni on a 12' frame I loaded the quilt with the length on the frame, instead of my normal procedure of loading by the width.  That way I could do fewer passes and avoid the back of my Lenni's head hitting the quilt building up on the roller as I worked to the bottom of the quilt.  Before loading the quilt, my measurements were 90"w on the top, middle and bottom of the quilt but it grew when I came to quilt the bottom border.  The quilt stayed very straight throughout the quilting process and my panto was not a heavy stitching pattern.  Any ideas about what went wrong and how I can avoid this problem in the future?  Oh and I did baste the quilt when I saw that it was getting too much fullness.

[mamu]

The only thing I can think of is that it stretched when rolling the quilt.  Since it was a T-shirt quilt, it should have been basted through out prior to quilting no matter which direction you had loaded the quilt top.  I do not trust T-shirt quilts to not stretch, even if they had the proper interfacing on the shirt part, as they love to mess with you when quilting....lol.  

 

[Casual Quilter]

Wow, thank you for the advice.  Yes I did baste the quilt but only when I noticed the stretching on the bottom of the quilt.  Just another reason not to do T-Shirt quilts.  

I hope that spring has come to Montana.  It will be edging up to the high 90's here in the Palm Desert this week.

Thanks again.