Any suggestions? HEAVY stabilizer used on T shirt squares
 

I am making a T shirt quilt for a friend. She had already cut the shirts and ironed on a fusible backing. The BIG problem is she used a heavy weight stabilizer....something I would use for embroidery or even purses. She said that is what the person at Joanns told her to get. The weight of the shirts with this stabilizer is very heavy and so different from the cotton she bought for the sashing and borders I am so afraid this quilt will turn out to be so stiff that it won't be able to be used as a "cuddle up" quilt. Is there anything I can do to this to make it better?

Stabilizers can sometimes be removed by using an iron and steaming them again so that the stabilizer loosens up. Could you get a piece from her and some of the extra tee shirt fabric to make a test?

Find out what the stabilizer name and number is and look it up on the internet. Sometimes, what is very heavy to begin with will soften up after washing.

..and if you cannot remove the "cardboard", if it were me I would just give it back to her with sincere apology......most of the time those really stiff interfacing so are not to be machine stitched on.....

I took a piece of the interfacing and washed it and it is still too thick. Some of the pieces are easy to pull off without harming the shirts, and some I tried to steam and it didn't come off. I would love to tell that salesperson at Joanns a thing or two about quilting. Remember the good old days when the people that worked in fabric stores actually sewed and knew stuff?

Sorry to hear about the poor advice. Perhaps the quilt would be better served as a wall hanger or draped over a railing for display. Maybe a lightweight fleece on the back would complement this one.
So many memories involved with those shirts, did one for a grand dau and they were sorority shirts so they were event related.