thank you all. I just took the plastic cover apart to get the measurments and did some math for the size of the fourpatches. An easy way to make them I saw on quilters tv. Then I made the FMQ (there is a great website about 365 quiltpatterns) and then sewed the three pieces together. And the best thing: the same size will fit my sewing machine, just have to come up with a new idea.
I would love to have some of you infected and look forward to see your covers