Puffiness in the center of a star quilt

[JudithA]

I'm making a quilt with a star in the middle, and there is puffiness in the center of the star. I was wondering how it could be fixed.

[bbquiltmaker]

Windypooh, it’s either the cutting or the sewing. If the pieces were cut accurately, the seam allowances are most likely less than 1/4”. Check all seam allowances that find the skimpy ones.

[HelenW]

I'm making a quilt with a star in the middle, and there is puffiness in the center of the star. I was wondering how it could be fixed.

Windypooh, I like your choice and placement of your colors in your lone star. Hopefully Barbara's tips solve the volcano in your center. There is another possible reason it does not lay flat and that is may have stretched the bias edges of the diamonds. Also, you may have pressed the strips in a bow shape which can distort the final larger diamond.
If the diamond are even a fraction off or not assembled accurately, it is not going to make the 360 degrees needed in the center. I have made 3 or 4 large lonestar quilts
and one was horrible. I had a similar situation. I ended up putting a fussy cut circle over the center area appliquing it to the top, and then cut away the center mess from behind.
It looked fine after that and everyone thought It was the design of the pattern. Sometimes correcting errors makes it look different that the original pattern, but work.
Your next problem will be if your diamonds are not true shaped diamonds, those setting squares are going to have a problem of not laying flat either. Jordon fabric has a good video on making a lone star. If you watch it, maybe it will help you figure where your problem started. HelenW