Thank you so much for your advice. My machine does have a 9inch harp but the quilt does get a lot a pushing and pulling. I gave up on pinning because I really struggled to get fabric crease free. As I'm unpicking I'm seeing that a lot of the areas which are puckered, the stitched have run really close together so I think there is probably an issue with the quilt getting hung up as I'm manoeuvring it. I've taken a few classes and worked with 14" sandwiches it's when I'm doing a whole quilt that I'm encountering problems. I'm going to straight pin the areas which need resewing, I know once it's washes the smaller puckers will disappear but this is a gift so want it to be as good as I can get it.